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java.util.Currency的Mongo Spring数据问题

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得到错误“在实体类java.util.Currency上找不到属性null”

嗨,我有文档类

@Document
@JsonInclude(Include.NON_NULL)
public class Course {
    @Id
    private String id;
    private String title;
    private Currency curr;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public Currency getCurr() {
        return curr;
    }

    public void setCurr(Currency curr) {
        this.curr = curr;
    }

}

在对数据进行POST请求给我的服务时

{"title":"my title","curr":"INR"}

我得到回应

 {
   "id": "56b0aa010364310e094c5f30",
   "title": "my title",
   "curr": "INR"
 }

但是当我获取时我得到了错误

: Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.data.mapping.model.MappingException: No property null found on entity class java.util.Currency to bind constructor parameter to!] with root cause
org.springframework.data.mapping.model.MappingException: No property null found on entity class java.util.Currency to bind constructor parameter to!

和回应为

{
   "timestamp": 1454419040321,
   "status": 500,
   "error": "Internal Server Error",
   "exception": "org.springframework.data.mapping.model.MappingException",
   "message": "No property null found on entity class java.util.Currency to bind constructor parameter to!",
   "path": "/56b0aa010364310e094c5f30"

}

我正在使用SpringBoot 1.3.2,而Jackons版本是2.6.5

在stackoverflow上也有类似的问题,但已被删除.
我做错了什么？

完整的堆栈跟踪

org.springframework.data.mapping.model.MappingException: No property null found on entity class java.util.Currency to bind constructor parameter to!
at org.springframework.data.mapping.model.PersistentEntityParameterValueProvider.getParameterValue(PersistentEntityParameterValueProvider.java:74) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.mapping.model.SpELExpressionParameterValueProvider.getParameterValue(SpELExpressionParameterValueProvider.java:63) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.convert.ReflectionEntityInstantiator.createInstance(ReflectionEntityInstantiator.java:71) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.convert.ClassGeneratingEntityInstantiator.createInstance(ClassGeneratingEntityInstantiator.java:83) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:251) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:231) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.readValue(MappingMongoConverter.java:1186) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.access$200(MappingMongoConverter.java:78) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter$MongoDbPropertyValueProvider.getPropertyValue(MappingMongoConverter.java:1134) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.getValueInternal(MappingMongoConverter.java:870) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter$1.doWithPersistentProperty(MappingMongoConverter.java:283) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter$1.doWithPersistentProperty(MappingMongoConverter.java:271) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mapping.model.BasicPersistentEntity.doWithProperties(BasicPersistentEntity.java:309) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:271) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:231) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:191) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:187) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.convert.MappingMongoConverter.read(MappingMongoConverter.java:78) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.MongoTemplate$ReadDbObjectCallback.doWith(MongoTemplate.java:2224) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.MongoTemplate.executeFindOneInternal(MongoTemplate.java:1855) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.MongoTemplate.doFindOne(MongoTemplate.java:1672) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.core.MongoTemplate.findById(MongoTemplate.java:614) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at org.springframework.data.mongodb.repository.support.SimpleMongoRepository.findOne(SimpleMongoRepository.java:119) ~[spring-data-mongodb-1.8.2.RELEASE.jar:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_66]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_66]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:483) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:468) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:440) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:61) ~[spring-data-commons-1.11.2.RELEASE.jar:na]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:208) ~[spring-aop-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at com.sun.proxy.$Proxy125.findOne(Unknown Source) ~[na:na]
at com.wiziq.microservice.course.service.CourseService.getCourseById(CourseService.java:16) ~[classes/:na]
at com.wiziq.microservice.course.controller.CourseController.getCourseById(CourseController.java:24) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_66]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_66]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_66]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_66]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:222) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:814) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:737) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:969) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:860) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:845) ~[spring-webmvc-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration$ApplicationContextHeaderFilter.doFilterInternal(EndpointWebMvcAutoConfiguration.java:237) ~[spring-boot-actuator-1.3.2.RELEASE.jar:1.3.2.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.cloud.sleuth.instrument.web.TraceFilter.doFilterInternal(TraceFilter.java:148) ~[spring-cloud-sleuth-core-1.0.0.M4.jar:1.0.0.M4]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:111) ~[spring-boot-actuator-1.3.2.RELEASE.jar:1.3.2.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:87) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:103) ~[spring-boot-actuator-1.3.2.RELEASE.jar:1.3.2.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.4.RELEASE.jar:4.2.4.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212) ~[tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:521) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1096) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:674) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500) [tomcat-embed-core-8.0.30.jar:8.0.30]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456) [tomcat-embed-core-8.0.30.jar:8.0.30]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_66]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_66]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.0.30.jar:8.0.30]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_66]

解决方法:

Spring Data MongoDB对象映射系统当前不支持开箱即用的Currency类型.您可以通过提供核心Spring Converter的自定义实现为described in the reference documentation,来教Spring Data MongoDB如何转换该类型的实例.

public class CustomMongoConfiguration extends AbstractMongoConfiguration {

  @Bean
  @Override
  public CustomConversions customConversions() {

    Converter<Currency, String> currencyToString = source -> source.toString();
    Converter<String, Currency> stringToCurrency = source -> Currency.getInstance(source);

    return new CustomConversions(Arrays.asList(currencyToString, stringToCurrency));
  }
}

由于转换为String似乎很简单,因此我创建了a ticket在即将发布的Spring Data MongoDB版本中解决.

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JavaScript数据容量单位转换（KB B MB GB....）【代码】

数据容量单位转换（KB B MB GB....）function bytesToSize(bytes) { if (bytes === 0) return '0 B'; var k = 1000, // or 1024 sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'], i = Math.floor(Math.log(bytes) / Math.log(k)); return (bytes / Math.pow(k, i)).toPrecision(3) + ' ' + sizes[i]; }原文：http://blog.51cto.com/dd118/2136481

java project如何连接数据库【图】

1，首先从mysql的官网上下载mysql-connector-java-5.1.44.zip2，选择downloads下的community3,在Community下选择MySql Connectors4,下面是MySQL Connectors的版本，我们选择Connector/J5,选择zip的文件包，进行下载。6，将下载好的文件包进行解压，找到其中mysql-connector-java-5.1.44-bin7,创建一个项目，项目进行右击，选择Add External Archives8,配置成功后的结果，如下图所示9，输入如下所示程序代码，以进行测试，实验表明：...

Java-基础-变量-关键字-四类八种数据类型-数据转换

java 概述　　　　public class Demo { //定义一个类　　 public static void main(String[] args) { //主方法，一切程序的起点 /* 在屏幕上打印输出 */ System.out.println("Hello World!"); 　　 }　　　　}（1） public class定义：类名称必须和文件名称保持一致，否则程序将无法编译，在一个*.Java之中只能有一个public 类；（2）主方法main()：主方法表示的是一...

java链接mysql数据库并且写入数据并且解决写入数据库乱码问题

package Test0; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FilenameFilter; import java.io.InputStream; import java.io.InputStreamReader; import java.sql.DriverManager; import java.util.regex.Matcher; import java.util.regex.Pattern; import com.mysql.jdbc.Connection; import com.mysql.jdbc.Statement; public class Test00 { static Connection co...

JS-安全检测JavaScript基本数据类型和内置对象的方法【代码】【图】

前言：在前端开发中经常会需要用到检测变量数据类型的需求，比如：判断一个变量是否为undefined或者null来进行下一步的操作，今天在阅读“编写高质量代码-改善JavaScript程序的188个建议”这本书的时候看到这个比较好的方法，在此小记一笔以备在以后的开发中使用。1：如下所示是我编写的演示代码<!DOCTYPE html><html><head><meta charset="utf-8"/><title>Index Page</title><script type="text/javascript">/*安全检测JavaScript...

Java千百问_06数据结构（008）_null属于哪种数据类型【代码】

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javascript学习-创建json对象数据，遍历

之前我已经有讲过后台返回json数据到前台，并在前台遍历json数据。这里讲下直接在JS里创建JSON数据，然后遍历使用~创建代码如下：（创建的是JSON对象） var YearSelect = {};var Year = 2014;var DateOption;for (var i = Year; i < Year + 12; i++) {DateOption = {'Year':i, 'Month':i-Year+1}; // alert(DateOption.Year)YearSelect[i] = DateOption;} 这里是创建一个JSON对象，包括了年份和月份的数据。我为什么创建JSON对象...

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Java在运行项目时候，点击右键的弹框，...nacos配置中心超时问题：java.net.Conn...Java的设计模式（7）— 生产者-消费者模...基于DOM4j和POI实现的XML文件转换为XLS...如何在Java中创建一些变量类型别名使用java8的Stream统计字符串数组中每一...idea插件篇之java内存分析工具(JProfil...cannot cast 'java.lang.Integer' to '...java – Bootstrap.properties中Spring...Java8利用stream流实现数字排序和中文排...

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java.util.Currency的Mongo Spring数据问题

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