java.lang.LinkageError：加载器约束违规：解析方法时“org.jboss.resteasy.client.core.executors.ApacheHttpClient4Executor

Question

JSF Web应用程序尝试从Java EE Web服务检索资源。 JSF Web应用程序运行正常。自从我将Http客户端源添加到反向Web服务资源以来，JBoss实例声称：

15:29:47,689 SEVERE [javax.enterprise.resource.webcontainer.jsf.application] (http--0.0.0.0-443-1) Error Rendering View[/index.xhtml]: javax.el.ELException: /surfaceParts/sideBarLeft.xhtml @14,79 value="#{categories.cats}": java.lang.LinkageError: loader constraint violation: when resolving method "org.jboss.resteasy.client.core.executors.ApacheHttpClient4Executor.<init>(Lorg/apache/http/client/HttpClient;Lorg/apache/http/protocol/HttpContext;)V" the class loader (instance of org/jboss/modules/ModuleClassLoader) of the current class, at/fhj/ase/ssl/SSLClientHelper, and the class loader (instance of org/jboss/modules/ModuleClassLoader) for resolved class, org/jboss/resteasy/client/core/executors/ApacheHttpClient4Executor, have different Class objects for the type xecutors.ApacheHttpClient4Executor.<init>(Lorg/apache/http/client/HttpClient;Lorg/apache/http/protocol/HttpContext;)V used in the signature
    at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:114) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIData.getValue(UIData.java:731) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIData.getDataModel(UIData.java:1798) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIData.setRowIndexWithoutRowStatePreserved(UIData.java:484) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIData.setRowIndex(UIData.java:473) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:81) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:820) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIData.encodeBegin(UIData.java:1118) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1777) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1779) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:402) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:489) [jbossweb-7.0.13.Final.jar:]
    at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
    at java.lang.Thread.run(Unknown Source) [rt.jar:1.7.0_25]
Caused by: java.lang.LinkageError: loader constraint violation: when resolving method "org.jboss.resteasy.client.core.executors.ApacheHttpClient4Executor.<init>(Lorg/apache/http/client/HttpClient;Lorg/apache/http/protocol/HttpContext;)V" the class loader (instance of org/jboss/modules/ModuleClassLoader) of the current class, at/fhj/ase/ssl/SSLClientHelper, and the class loader (instance of org/jboss/modules/ModuleClassLoader) for resolved class, org/jboss/resteasy/client/core/executors/ApacheHttpClient4Executor, have different Class objects for the type xecutors.ApacheHttpClient4Executor.<init>(Lorg/apache/http/client/HttpClient;Lorg/apache/http/protocol/HttpContext;)V used in the signature
    at at.fhj.ase.ssl.SSLClientHelper.getSSLClientRequest(SSLClientHelper.java:71) [classes:]
    at at.fhj.ase.beans.Categories.getCats(Categories.java:39) [classes:]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_25]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) [rt.jar:1.7.0_25]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) [rt.jar:1.7.0_25]
    at java.lang.reflect.Method.invoke(Unknown Source) [rt.jar:1.7.0_25]
    at javax.el.BeanELResolver.getValue(BeanELResolver.java:302) [jboss-el-api_2.2_spec-1.0.0.Final.jar:1.0.0.Final]
    at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at org.apache.el.parser.AstValue.getValue(AstValue.java:169) [jbossweb-7.0.13.Final.jar:]
    at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189) [jbossweb-7.0.13.Final.jar:]
    at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) [jsf-impl-2.1.7-jbossorg-2.jar:]
    ... 36 more

我很确定HttpClient源很好，因为它与Web服务端用于JUnit测试的内容相同。

ProjectSetup： Web服务部署在JBoss AS7.1上（到目前为止工作正常）JSF Web客户端部署在同一个JBoss实例上。两者都是通过Eclipse启动的。 JSF Web客户端的Deployment程序集如下所示：

我假设链接错误是由外部（BuildPath＆amp; DeploymentAssembly）添加的apache http客户端库引起的。但是我该如何解决这个问题？

如果您需要更多详细信息，请告诉我。 我非常感谢任何帮助！

Answer 1

您看到错误的原因是因为RestEasy依赖于httpclient jar，它是作为jboss模块提供的。您提供的版本与JBoss提供的版本相冲突。

为什么需要将HTTPClient jar与您的Web应用程序打包？是为了一些休息客户电话？在这种情况下，您应该使用RestEasy，它是JBoss AS7上的默认JAX-RS实现。这将是一个更好的框架，用于此目的。

您的另一个选择是在org.apache.httpcomponents的{​​{1}}模块中添加依赖项，并从WEB-INF\jboss-deployment-structure.xml中移除http客户端广告。