如何修复试图在 Jersey 中实例化 CloseableHttpClient 的 NullPointerException 2.x

Question

我有一个球衣 2.x Web 应用程序，其中有一个业务对象试图通过调用外部服务来处理请求。每当我尝试实例化 CloseableHttpClient 时，它都会抛出 NullPointerException。

我尝试使用旧的 commons-httpclient 库，它做的事情完全一样。

我发现它真的很奇怪，因为在 Jersey 1.x 网络应用程序中使用了相同的代码并且它工作得很好。

有人知道这是为什么吗？是不是因为 oc jersey container 而我需要使用 jersey client api 的？

下面的两个示例都会产生错误。不管我使用哪个库（当然是单独测试的）。

// Using the httpclient-4.3.6
ClonableHttpClient httpClient = HttpClients.createDefault();

// Using commons-httpclient-3.1
HttpClient httpClient = new HttpClient();

这是 stackt 比赛：

Exception:

java.lang.NullPointerException
    at com.valspar.security.bso.WservicesSecurityManager.authenticateInMobilesecure(WservicesSecurityManager.java:549)
    at com.valspar.security.SecurityServiceImpl.doChiptapLogin(SecurityServiceImpl.java:165)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory.invoke(ResourceMethodInvocationHandlerFactory.java:81)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.run(AbstractJavaResourceMethodDispatcher.java:144)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:161)
    at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$TypeOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:204)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:99)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:389)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:347)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:102)
    at org.glassfish.jersey.server.ServerRuntime.run(ServerRuntime.java:309)
    at org.glassfish.jersey.internal.Errors.call(Errors.java:271)
    at org.glassfish.jersey.internal.Errors.call(Errors.java:267)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:267)
    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317)
    at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:292)
    at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1139)
    at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:454)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:386)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:334)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:221)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.filters.HttpHeaderSecurityFilter.doFilter(HttpHeaderSecurityFilter.java:126)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at com.valspar.security.filters.TomcatAccessLogFilter.doFilter(TomcatAccessLogFilter.java:49)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
    at org.apache.coyote.ajp.AjpAprProcessor.process(AjpAprProcessor.java:188)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
    at org.apache.tomcat.util.net.AprEndpoint$SocketWithOptionsProcessor.run(AprEndpoint.java:2512)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1152)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:622)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:748)

Answer 1

我已经尝试了所有方法但没有结果，所以我最终做的是使用 jersey 客户端库，这似乎工作正常。这不一定回答我的问题，但它让我继续前进。

如何修复试图在 Jersey 中实例化 CloseableHttpClient 的 NullPointerException 2.x

How to fix NullPointerException trying to instantiate CloseableHttpClient in Jersey 2.x

java

jersey-2.0

apache-httpclient-4.x