Java 如何在Liferay 5.2.3中使用guava-18.0.jar

我正在Liferay 5.2.3中开发我的第一个portlet，我对这个领域非常陌生。 今天，我想使用guava-18.0.jar从Lists.revers方法中获益，我将jar文件放在portlet的lib文件夹中。它给了我这个错误：

15:55:49,905 ERROR [[fozhan]:711] Servlet.service() for servlet fozhan threw exception
java.lang.UnsupportedClassVersionError: Bad version number in .class file
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
        at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1876)
        at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:889)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1353)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1232)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
        at com.sample.jsp.portlet.JSPPortlet.processAction(JSPPortlet.java:95)
        at com.sun.portal.portletcontainer.appengine.filter.FilterChainImpl.doFilter(FilterChainImpl.java:98)
        at com.liferay.portal.kernel.portlet.PortletFilterUtil.doFilter(PortletFilterUtil.java:57)
        at com.liferay.portal.kernel.servlet.PortletServlet.service(PortletServlet.java:100)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:679)
        at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:584)
        at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:497)
        at com.liferay.portlet.InvokerPortletImpl.invoke(InvokerPortletImpl.java:618)
        at com.liferay.portlet.InvokerPortletImpl.invokeAction(InvokerPortletImpl.java:664)
        at com.liferay.portlet.InvokerPortletImpl.processAction(InvokerPortletImpl.java:359)
        at com.liferay.portal.action.LayoutAction.processPortletRequest(LayoutAction.java:604)
        at com.liferay.portal.action.LayoutAction.processLayout(LayoutAction.java:428)
        at com.liferay.portal.action.LayoutAction.execute(LayoutAction.java:195)
        at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
        at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
        at com.liferay.portal.struts.PortalRequestProcessor.process(PortalRequestProcessor.java:157)
        at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
        at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:627)
        at com.liferay.portal.servlet.MainServlet.callParentService(MainServlet.java:608)
        at com.liferay.portal.servlet.MainServlet.service(MainServlet.java:846)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:679)
        at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:461)
        at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:399)
        at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:301)
        at com.liferay.portal.servlet.FriendlyURLServlet.service(FriendlyURLServlet.java:143)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.strip.StripFilter.processFilter(StripFilter.java:142)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:94)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.gzip.GZipFilter.processFilter(GZipFilter.java:140)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.secure.SecureFilter.processFilter(SecureFilter.java:282)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:94)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.cache.CacheFilter.processFilter(CacheFilter.java:425)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.autologin.AutoLoginFilter.processFilter(AutoLoginFilter.java:257)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.sso.opensso.OpenSSOFilter.processFilter(OpenSSOFilter.java:73)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.sharepoint.SharepointFilter.processFilter(SharepointFilter.java:193)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.virtualhost.VirtualHostFilter.doFilter(VirtualHostFilter.java:191)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.servlet.filters.threadlocalcache.ThreadLocalCacheFilter.processFilter(ThreadLocalCacheFilter.java:55)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:91)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:154)
        at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:94)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:738)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:875)
        at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
        at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
        at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
        at java.lang.Thread.run(Thread.java:595)
15:55:49,986 ERROR [jsp:165] java.lang.UnsupportedClassVersionError: Bad version number in .class file
        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
        at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1876)
        at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:889)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1353)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1232)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
        at com.sample.jsp.portlet.JSPPortlet.processAction(JSPPortlet.java:95)
        at com.sun.portal.portletcontainer.appengine.filter.FilterChainImpl.doFilter(FilterChainImpl.java:98)
        at com.liferay.portal.kernel.portlet.PortletFilterUtil.doFilter(PortletFilterUtil.java:57)
        at com.liferay.portal.kernel.servlet.PortletServlet.service(PortletServlet.java:100)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:679)
        at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:584)
        at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:497)
        at com.liferay.portlet.InvokerPortletImpl.invoke(InvokerPortletImpl.java:618)
        at com.liferay.portlet.InvokerPortletImpl.invokeAction(InvokerPortletImpl.java:664)
        at com.liferay.portlet.InvokerPortletImpl.processAction(InvokerPortletImpl.java:359)

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这可能是由你的Liferay版本引起的。Guava Release 10.0于2011年9月28日发布，可能是在liferay 5.2.3之后发布的。您完全可以使用它：

Collections.reverse(list.clone());

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请注意，这比列表要做的工作多得多。反向复制然后移动所有元素，而不是仅仅创建一个视图，而且它并不像编写的那样工作，因为您需要先将列表副本分配给变量。