我使用了这个答案的解决方案：Get list of JSON objects with Spring RestTemplate它完美地运作.它完全符合我的需要.ProcessDefinition[] response = restTemplate.getForObject(url, ProcessDefinition[].class);是否应该：return Arrays.asList(response);或者这样会更好：return Arrays.asList(Optional.ofNullable(response).orElse(new ProcessDefinition[0]));附：很抱歉开始新主题,但我的业力不允许我评论答案.解决方法:是的...
我正在使用以下服务创建RESTFul Web服务：@RequestMapping(value = "/test", produces = "application/json", method = RequestMethod.GET) public ResponseEntity<List<GenericModel>> returnEmpty() {List<GenericModel> genericModelList = new ArrayList<>();HttpHeaders headers = new HttpHeaders();headers.add("Content-Type", "application/json; charset=utf-8");return responseEntity = new ResponseEntity<>(genericM...
我想将以下xml解组为另一个父对象,如下所述.但它总是返回NULL. 传入XML：<contentFiles> <contentFile> <contentFileName>cwb_reg_content_IB20C0F504A9A11E281E4C8BF76F4977C.pdf</contentFileName> <title><![CDATA[SEC No-Action Guidance Expanding the Definition of “Ready Market” for Certain Foreign Equity Securities]]></title> <sourcePublicationDate>20121219</sourcePublicationDate> <alternateDocNumbers><alt...
从Java 7 Update 25开始,Applet的方法getCodeBase()似乎为本地applet返回NULL.我没有在Java 7u25发行说明中找到任何可以宣布/解释此更改的内容,但我发现了一个email discussion,声称这个更改实际上是有意的. 任何人都可以帮我找到资源/文档,在那里我可以了解更多有关此更改的信息吗？解决方法:发行说明在这里： http://www.oracle.com/technetwork/java/javase/7u25-relnotes-1955741.html 它在那里. “本地小程序返回NULL表示”
可以将null转换为任何类型吗？即以下代码是否有效public <T> T foo(Object object){return (T) object; }Duck duck = foo(new Duck()); // this worksDuck duck2 = foo(null); // should this work? Cat cat = foo(null); // should this work?// if they are both null, should this be true? boolean equality = duck2.equals(cat);我的问题是,是否’可投入任何东西’？解决方法:来自Javadocs： 还有一个特殊的null类型,表达式的...
我试图从ResourceResolverFactory获取对ResourceResolver的引用,如下所示：@Reference private ResourceResolverFactory resourceResolverFactory;public void someMethod() {Map<String, Object> authenticationMap = new HashMap<String, Object>();authenticationMap.put(ResourceResolverFactory.USER, "user");authenticationMap.put(ResourceResolverFactory.PASSWORD, "pwd");//This line returns NullPointerExceptionReso...
Hibernate – Query为Entity中的所有字段返回nullLong fooId = 39; Query query = getCurrentSession().createQuery("from FooEntity where deleted IS FALSE AND id=:fooId" ); query.setParameter( "fooId", fooId ); FooEntity fooEntity = ( FooEntity ) query.uniqueResult();检查FooEntity,显示以下结果(id=null, name=null, deleted=null)虽然相同的查询从db返回完美的结果select * from foo where deleted IS FALSE ...
我想在非root用户设备上运行可执行文件. 在java中使用以下命令Runtime.getRuntime().exec("/bin/chmod 744 /data/data/com.example.myapp/myBin"); Runtime.getRuntime().exec("/data/data/com.example.myapp/myBin");结果是Error running exec(). Command: [/data/data/com.example.myapp/myBin] Working Directory: null Environment: null我在这个问题上找到了很多问题但没有答案在我的案例中有效.如何正确执行二进制文件？解决...
我是MapReduce的新手,我正在尝试找到一个问题的解决方案.我正在尝试链接两个地图减少作业.第一个工作正在执行但在第二个工作我得到一个错误如下INFO mapreduce.Job: Task Id : attempt_1445271708293_0055_m_000000_1, Status : FAILED Error: java.io.IOException: Initialization of all the collectors failed. Error in last collector was :nullat org.apache.hadoop.mapred.MapTask.createSortingCollector(Map...
我有问题弄清楚为什么我的Jersey RESTful入口点找不到我在app服务器启动时配置的Spring Bean.尝试后它一直得到NullPointerException > Spring DI – Autowired property is null in a REST service> NullPointerException on @Autowired attribute with Jersey and Spring for REST service> @Autowired is not working with jersey and spring> Integrating both spring mvc and Jersey, getting a null pointer when viewing a j...
我正在尝试将在Inner类中创建的List’usrs’复制到不同的列表’team_memebers’.复制后,我尝试在FOR循环中迭代’team_memebers’,但是我得到’null object reference’错误.‘users’列表包含返回的对象,通过调试打印进行测试.public class ListNodeActivity extends AppCompatActivity {private ParseObject parse_task=null;private List<String> team_memebers=null;@Overrideprotected void onCreate(Bundle savedInstanceStat...
我从我的邮件帐户读取邮件时遇到问题并将其保存在我的数据库中.我的代码如下：Store store = null;Folder folder = null;Message message = null;Message[] messages = null;Object messagecontentObject = null;String sender = null;String subject = null;Multipart multipart = null;Part part = null;String contentType = null;String dateTime = "";String fileName = "";Session session = null;int count = 0;try {Proper...
我在服务中使用自动装配的构造函数,当在测试类中实例化时,会导致@Value注释返回null.自动装配依赖项直接解决了问题,但项目遵循使用基于构造函数的自动装配的惯例.我的理解是,在测试类中实例化服务并不是从Spring IoC容器创建它,导致@Value返回null.有没有办法使用基于构造函数的自动装配从IoC容器创建服务,而无需直接访问应用程序上下文？ 示例服务：@Component public class UpdateService {@Value("${update.success.table}")pri...
我使用Mockito 1.10.19创建测试来测试自定义RecyclerView适配器. (代码已经过简化以消除信息噪音,留下最简单的版本仍有问题)public class CustomAdapter extends RecyclerView.Adapter<CustomViewHolder> {private final Dependency dependency;public CustomAdapter(@NonNull Dependency dependency) {this.dependency = dependency;}public void refreshData() {dependency.refreshData();notifyDataSetChanged();}@Overridepubl...
我有一个名为stars的MySQL表,其中一个字段是id_num,默认值为NULL.我想通过java中的PreparedStatement选择id_num不为NULL的所有记录. 现在我正在尝试这个：private final String idStarsSQL = "select * from `stars` where id_num is not ?"; ...preparedStatement = (PreparedStatement) connection.prepareStatement(idStarsSQL); preparedStatement.setString(1, NULL); set = preparedStatement.executeQuery();但它不起作用.解...