Java从入门到实战之（28）Java 目录操作之练习
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内容图文
1、递归创建目录
使用 File 类的 mkdirs() 实现递归创建目录？
import java.io.File;
public class Main {
public static void main(String[] args) {
String directories = "D:\\a\\b\\c\\d\\e\\f\\g\\h\\i";
File file = new File(directories);
boolean result = file.mkdirs();
System.out.println("Status = " + result);
}
}
结果：
Status = true
2、删除目录
使用 File 类的 ofdir.isDirectory(), dir.list() 和 deleteDir() 方法在一个个删除文件后删除目录？
import java.io.File;
public class Main {
public static void main(String[] argv) throws Exception {
// 删除当前目录下的 test 目录
deleteDir(new File("./test"));
}
public static boolean deleteDir(File dir) {
if (dir.isDirectory()) {
String[] children = dir.list();
for (int i = 0; i < children.length; i++) {
boolean success = deleteDir
(new File(dir, children[i]));
if (!success) {
return false;
}
}
}
if(dir.delete()) {
System.out.println("目录已被删除！");
return true;
} else {
System.out.println("目录删除失败！");
return false;
}
}
}
结果：
目录已被删除！
3、判断目录是否为空
使用 File 类的 file.isDirectory() 和 file.list() 方法来判断目录是否为空？
import java.io.File;
public class Main
{
public static void main(String[] args)
{
File file = new File("./testdir"); // 当前目录下的 testdir目录
if(file.isDirectory()){
if(file.list().length>0){
System.out.println("目录不为空!");
}else{
System.out.println("目录为空!");
}
}else{
System.out.println("这不是一个目录!");
}
}
}
结果：
目录 D://Java/file.txt 不为空！
4、判断文件是否隐藏
使用 File 类的 file.isHidden() 方法来判断文件是否隐藏？
import java.io.File;
public class Main {
public static void main(String[] args) {
File file = new File("C:/Demo.txt");
System.out.println(file.isHidden());
}
}
结果：
True
5、获取目录大小
使用 File 类的 FileUtils.sizeofDirectory(File Name) 来获取目录的大小？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
dirSize(directories);
}
/**
* @Description: 目录文件的大小
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
public static void dirSize(String dir) {
File file=new File(dir);
long size= FileUtils.sizeOfDirectory(file);
System.out.println(dir+"的目录大小是："+size+"bytes");
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=50891:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 C:\文档\个人学习资料\IOTest\的目录大小是：79bytes Process finished with exit code 0
6、在指定目录中查找文件
使用 File 类的 dir.list() 方法在指定目录中查找所有文件列表？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
dirFindFile(directories);
}
/**
* @Description: 在指定目录中查找文件
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void dirFindFile(String dir)
{
File file=new File(dir);
String[] s=file.list();
if(s==null)
{
System.out.println("目录不存在");
}
else
{
for(String x:s)
{
System.out.println("文件名:"+x);
}
}
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=51845:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 文件名:01.txt 文件名:a 文件名:HelloWorld.txt 文件名:rainbow1.txt 文件名:rainbow2.txt 文件名:rainbowTest.txt Process finished with exit code 0
import java.io.*;
class Main {
public static void main(String[] args) {
File dir = new File("C:");
FilenameFilter filter = new FilenameFilter() {
public boolean accept
(File dir, String name) {
return name.startsWith("b");
}
};
String[] children = dir.list(filter);
if (children == null) {
System.out.println("目录不存在或它不是一个目录");
}
else {
for (int i=0; i < children.length; i++) {
String filename = children[i];
System.out.println(filename);
}
}
}
}
结果：
build build.xml
7、获取文件的上级目录
使用 File 类的 file.getParent() 方法来获取文件的上级目录？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
getParentDir(directories);
}
/**
* @Description: 获取文件父级目录
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void getParentDir(String dir)
{
File file=new File(dir);
System.out.println("文件上级目录是:"+file.getParent());
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=52575:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 文件上级目录是:C:\文档\个人学习资料 Process finished with exit code 0
8、获取目录最后修改时间
使用 File 类的 file.lastModified() 方法来获取目录的最后修改时间?
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
import java.util.Date;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
getLastModify(directories);
}
/**
* @Description: 获取目录最后修改时间
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void getLastModify(String dir)
{
File file=new File(dir);
System.out.println(dir+"的最后修改时间是："+new Date(file.lastModified()));
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=52675:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 C:\文档\个人学习资料\IOTest\的最后修改时间是：Mon Nov 09 14:27:33 CST 2020 Process finished with exit code 0
9、打印目录结构
使用 File 类的 file.getName() 和 file.listFiles() 方法来打印目录结构？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.IOException;
import java.util.Date;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
showDir(1,new File(directories));
}
/**
* @Description: 打印目录结构
* @Param: [indent, file]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void showDir(int indent, File file) {
for (int i = 0; i < indent; i++)
System.out.print('-');
System.out.println(file.getName());
if (file.isDirectory()) {
File[] files = file.listFiles();
for (int i = 0; i < files.length; i++)
showDir(indent + 4, files[i]);
}
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=52901:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 -IOTest -----01.txt -----a ---------b -------------c -----------------d ---------------------e -------------------------f -----------------------------g ---------------------------------h -----HelloWorld.txt -----rainbow1.txt -----rainbow2.txt -----rainbowTest.txt Process finished with exit code 0
10、遍历指定目录下的所有目录
如何使用 File 类的 list 方法来遍历指定目录下的所有目录？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.util.Date;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
ergodicDir(directories);
}
/**
* @Description: 遍历指定目录下的所有目录
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void ergodicDir(String dir)
{
File file=new File(dir);
File[] files=file.listFiles();
FileFilter fileFilter=new FileFilter() {
@Override
public boolean accept(File file1) {
return file1.isDirectory();
}
};
files=file.listFiles(fileFilter);
// System.out.println(files.length);
if(files.length==0)
{
System.out.println("目录不存在或它不是一个目录");
}
else
{
for(File x:files)
{
System.out.println(x.toString());
}
}
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=53058:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 C:\文档\个人学习资料\IOTest\a Process finished with exit code 0
11、输出指定目录下的所有文件
如何使用 File 类的 list 方法来输出指定目录下的所有文件？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.util.Date;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
ergodicFile(directories);
}
/**
* @Description: 遍历指定目录下的所有文件
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void ergodicFile(String dir) {
File file = new File(dir);
String list[]=file.list();
if(list==null)
{
System.out.println("目录不存在或它不是一个目录");
}
else
{
for (String x:list)
{
System.out.println(x);
}
}
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=53139:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 01.txt a HelloWorld.txt rainbow1.txt rainbow2.txt rainbowTest.txt Process finished with exit code 0
12、查看系统根目录
使用 File 类的 listRoots() 方法来输出系统所有根目录？
package Practice;
import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.util.Date;
/**
* @program: FlinkUdf
* @description: 文件目录
* @author: BigData
* @create: 2020-11-09 14:19
**/
public class Test1 {
public static void main(String[] args) {
String directories = "C:\\文档\\个人学习资料\\IOTest\\";
ergodicRootDir();
}
/**
* @Description: 遍历根目录
* @Param: [dir]
* @return: void
* @Author: BigData
* @Date: 2020/11/9
*/
private static void ergodicRootDir() {
//技巧：Ctrl+Alt+V快速生成变量名
File[] roots = File.listRoots();
System.out.println("系统所有根目录：");
for (File s:roots)
{
System.out.println(s.toString());
}
}
}
结果：
"C:\Program Files\Java\jdk1.8.0_221\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\lib\idea_rt.jar=53342:C:\Program Files\JetBrains\IntelliJ IDEA 2019.3.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_221\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_221\jre\lib\rt.jar;C:\app\FlinkUdf\target\test-classes;C:\Users\defaultuser0\.m2\repository\junit\junit\4.11\junit-4.11.jar;C:\Users\defaultuser0\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java-bridge_2.11\1.11.1\flink-table-api-java-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-java\1.11.1\flink-table-api-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-java\1.11.1\flink-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-lang3\3.3.2\commons-lang3-3.3.2.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-math3\3.5\commons-math3-3.5.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-runtime_2.11\1.11.1\flink-runtime_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-queryable-state-client-java\1.11.1\flink-queryable-state-client-java-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-hadoop-fs\1.11.1\flink-hadoop-fs-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-netty\4.1.39.Final-11.0\flink-shaded-netty-4.1.39.Final-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-jackson\2.10.1-11.0\flink-shaded-jackson-2.10.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-zookeeper-3\3.4.14-11.0\flink-shaded-zookeeper-3-3.4.14-11.0.jar;C:\Users\defaultuser0\.m2\repository\commons-cli\commons-cli\1.3.1\commons-cli-1.3.1.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-actor_2.11\2.5.21\akka-actor_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\config\1.3.3\config-1.3.3.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-java8-compat_2.11\0.7.0\scala-java8-compat_2.11-0.7.0.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-stream_2.11\2.5.21\akka-stream_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\reactivestreams\reactive-streams\1.0.2\reactive-streams-1.0.2.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\ssl-config-core_2.11\0.3.7\ssl-config-core_2.11-0.3.7.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-protobuf_2.11\2.5.21\akka-protobuf_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\com\typesafe\akka\akka-slf4j_2.11\2.5.21\akka-slf4j_2.11-2.5.21.jar;C:\Users\defaultuser0\.m2\repository\org\clapper\grizzled-slf4j_2.11\1.3.2\grizzled-slf4j_2.11-1.3.2.jar;C:\Users\defaultuser0\.m2\repository\com\github\scopt\scopt_2.11\3.5.0\scopt_2.11-3.5.0.jar;C:\Users\defaultuser0\.m2\repository\org\xerial\snappy\snappy-java\1.1.4\snappy-java-1.1.4.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill_2.11\0.7.6\chill_2.11-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\com\twitter\chill-java\0.7.6\chill-java-0.7.6.jar;C:\Users\defaultuser0\.m2\repository\org\lz4\lz4-java\1.6.0\lz4-java-1.6.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-guava\18.0-11.0\flink-shaded-guava-18.0-11.0.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-java_2.11\1.11.1\flink-streaming-java_2.11-1.11.1-tests.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-api\1.7.15\slf4j-api-1.7.15.jar;C:\Users\defaultuser0\.m2\repository\com\google\code\findbugs\jsr305\1.3.9\jsr305-1.3.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\force-shading\1.11.1\force-shading-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-planner-blink_2.11\1.11.1\flink-table-planner-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala_2.11\1.11.1\flink-table-api-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-api-scala-bridge_2.11\1.11.1\flink-table-api-scala-bridge_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-runtime-blink_2.11\1.11.1\flink-table-runtime-blink_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\janino\3.0.9\janino-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\codehaus\janino\commons-compiler\3.0.9\commons-compiler-3.0.9.jar;C:\Users\defaultuser0\.m2\repository\org\apache\calcite\avatica\avatica-core\1.16.0\avatica-core-1.16.0.jar;C:\Users\defaultuser0\.m2\repository\org\reflections\reflections\0.9.10\reflections-0.9.10.jar;C:\Users\defaultuser0\.m2\repository\org\javassist\javassist\3.19.0-GA\javassist-3.19.0-GA.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-streaming-scala_2.11\1.11.1\flink-streaming-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-scala_2.11\1.11.1\flink-scala_2.11-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-reflect\2.11.12\scala-reflect-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-library\2.11.12\scala-library-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\scala-compiler\2.11.12\scala-compiler-2.11.12.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-xml_2.11\1.0.5\scala-xml_2.11-1.0.5.jar;C:\Users\defaultuser0\.m2\repository\org\scala-lang\modules\scala-parser-combinators_2.11\1.0.4\scala-parser-combinators_2.11-1.0.4.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-table-common\1.11.1\flink-table-common-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-core\1.11.1\flink-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-annotations\1.11.1\flink-annotations-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-metrics-core\1.11.1\flink-metrics-core-1.11.1.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\kryo\kryo\2.24.0\kryo-2.24.0.jar;C:\Users\defaultuser0\.m2\repository\com\esotericsoftware\minlog\minlog\1.2\minlog-1.2.jar;C:\Users\defaultuser0\.m2\repository\org\objenesis\objenesis\2.1\objenesis-2.1.jar;C:\Users\defaultuser0\.m2\repository\org\apache\commons\commons-compress\1.20\commons-compress-1.20.jar;C:\Users\defaultuser0\.m2\repository\org\apache\flink\flink-shaded-asm-7\7.1-11.0\flink-shaded-asm-7-7.1-11.0.jar;C:\Users\defaultuser0\.m2\repository\com\alibaba\fastjson\1.2.73\fastjson-1.2.73.jar;C:\Users\defaultuser0\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\defaultuser0\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\defaultuser0\.m2\repository\net\sf\json-lib\json-lib\2.4\json-lib-2.4-jdk15.jar;C:\Users\defaultuser0\.m2\repository\commons-beanutils\commons-beanutils\1.8.0\commons-beanutils-1.8.0.jar;C:\Users\defaultuser0\.m2\repository\commons-collections\commons-collections\3.2.1\commons-collections-3.2.1.jar;C:\Users\defaultuser0\.m2\repository\commons-lang\commons-lang\2.5\commons-lang-2.5.jar;C:\Users\defaultuser0\.m2\repository\commons-logging\commons-logging\1.1.1\commons-logging-1.1.1.jar;C:\Users\defaultuser0\.m2\repository\net\sf\ezmorph\ezmorph\1.0.6\ezmorph-1.0.6.jar;C:\Users\defaultuser0\.m2\repository\org\json\json\20180813\json-20180813.jar" Practice.Test1 系统所有根目录： C:\ Process finished with exit code 0
13、查看当前工作目录
使用 System 的 getProperty() 方法来获取当前的工作目录？
class Main {
public static void main(String[] args) {
String curDir = System.getProperty("user.dir");
System.out.println("你当前的工作目录为 :" + curDir);
}
}
结果：
你当前的工作目录为 :/www/java
14、遍历目录
使用 File 类的 dir.isDirectory() 和 dir.list() 方法来遍历目录？
import java.io.File;
public class Main {
public static void main(String[] argv) throws Exception {
System.out.println("遍历目录");
File dir = new File("/www/java"); //要遍历的目录
visitAllDirsAndFiles(dir);
}
public static void visitAllDirsAndFiles(File dir) {
System.out.println(dir);
if (dir.isDirectory()) {
String[] children = dir.list();
for (int i = 0; i < children.length; i++) {
visitAllDirsAndFiles(new File(dir, children[i]));
}
}
}
}
结果：
遍历目录 /www/java /www/java/Car.class /www/java/FileUtil.class /www/java/FileUtil.java /www/java/HelloWorld.class /www/java/HelloWorld.java /www/java/HelloWorldDebug.class /www/java/HelloWorldDebug.java /www/java/Main$1.class /www/java/Main.class /www/java/Main.java /www/java/MainClass.class /www/java/MainClass.java /www/java/MyClass.class /www/java/outfilename /www/java/test.log
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