WAS 8.5：java.lang.ClassCastException：org.apache.xerces.jaxp.SAXParserFactoryImpl与javax.xml.parsers.SAXParserFactory不兼容

Question

我正在Websphere Application Server 8.5中部署J2EE Web应用程序。

Web应用程序具有包含所有第三方库的共享库。所有内部编码的库都在WEB-INF / lib文件夹中。

问题是只有一些jsps WAS会抛出以下异常。

我认为它与xercesImpl-2.8.1.jar有关，但我不明白为什么它会抛出这个异常以及它为什么只抛出一些页面。

在tomcat中它运行得很好。

java.lang.ClassCastException: org.apache.xerces.jaxp.SAXParserFactoryImpl incompatible with javax.xml.parsers.SAXParserFactory
    at javax.xml.parsers.SAXParserFactory.newInstance(Unknown Source)
    at org.apache.taglibs.standard.tlv.JstlBaseTLV.validate(JstlBaseTLV.java:152)
    at org.apache.taglibs.standard.tlv.JstlCoreTLV.validate(JstlCoreTLV.java:96)
    at com.ibm.ws.jsp.translator.visitor.validator.ValidateVisitor.validateTagLib(ValidateVisitor.java:1129)
    at com.ibm.ws.jsp.translator.visitor.validator.ValidateVisitor.visitJspRootStart(ValidateVisitor.java:491)
    at com.ibm.ws.jsp.translator.visitor.JspVisitor.processJspElement(JspVisitor.java:233)
    at com.ibm.ws.jsp.translator.visitor.JspVisitor.visit(JspVisitor.java:216)
    at com.ibm.ws.jsp.translator.JspTranslator.processVisitors(JspTranslator.java:127)
    at com.ibm.ws.jsp.translator.utils.JspTranslatorUtil.translateJsp(JspTranslatorUtil.java:254)
    at com.ibm.ws.jsp.translator.utils.JspTranslatorUtil.translateJspAndCompile(JspTranslatorUtil.java:121)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionServletWrapper.translateJsp(AbstractJSPExtensionServletWrapper.java:535)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionServletWrapper._checkForTranslation(AbstractJSPExtensionServletWrapper.java:452)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionServletWrapper.checkForTranslation(AbstractJSPExtensionServletWrapper.java:283)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionProcessor.findWrapper(AbstractJSPExtensionProcessor.java:456)
    at com.ibm.ws.jsp.webcontainerext.AbstractJSPExtensionProcessor.getServletWrapper(AbstractJSPExtensionProcessor.java:337)
    at com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:963)
    at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.dispatch(WebAppRequestDispatcher.java:1384)
    at com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.forward(WebAppRequestDispatcher.java:193)
    at com.ieci.tecdoc.isicres.servlets.QryInitAdvanSearch.doWork(QryInitAdvanSearch.java:209)
    at com.ieci.tecdoc.isicres.servlets.QryInitAdvanSearch.doGet(QryInitAdvanSearch.java:67)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:575)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:668)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1214)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:774)
    at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:456)
    at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:178)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.invokeTarget(WebAppFilterChain.java:125)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:92)
    at com.ieci.tecdoc.isicres.filters.URLCheckFilter.doFilter(URLCheckFilter.java:106)
    at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:192)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:89)
    at com.ieci.tecdoc.isicres.filters.LoginCheckFilter.doFilter(LoginCheckFilter.java:119)
    at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:192)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:89)
    at com.ieci.tecdoc.isicres.filters.XSSFilter.doFilter(XSSFilter.java:72)
    at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:192)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:89)
    at com.ieci.tecdoc.isicres.filters.UTF8Filter.doFilter(UTF8Filter.java:65)
    at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:192)
    at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:89)
    at com.ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter(WebAppFilterManager.java:926)
    at com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1023)
    at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:3703)
    at com.ibm.ws.webcontainer.webapp.WebGroup.handleRequest(WebGroup.java:304)
    at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:962)
    at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1662)
    at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:195)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:458)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewRequest(HttpInboundLink.java:522)
    at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.processRequest(HttpInboundLink.java:311)
    at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:87)
    at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:165)
    at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
    at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
    at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
    at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:204)
    at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:775)
    at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:905)

Answer 1

基本上，不需要打包实现标准化API的库（如javax.xml），因为大多数库都已由JRE或应用程序服务器提供。这样可以避免各种不兼容问题，例如您所面临的问题。

如果您仍需要使用特定版本的Xerces，请将Web模块的类加载策略更改为PARENT_LAST。在这种情况下，将从WEB-INF/lib获取库。但这并不能保证你不会遇到问题。

总结一下：从应用程序中删除xercesImpl-2.8.1.jar。您的操作环境提供XML解析器实现。在大多数情况下，您不需要知道哪一个。

Answer 2

我解决了它改变共享库的关联。

最初，xerces库作为应用程序级别的共享库包含在内，因此这些库之前加载的是应用程序服务器。

我将共享库关联更改为模块级，现在加载了这些库，而不是应用程序服务器，并且异常消失了。