javax.servlet.jsp.PageContext.getELContext()Ljavax/el/ELContext问题

问题：
[ERROR] 2013-12-09 15:03:20,740 method:org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:253)
Servlet.service() for servlet org.apache.jsp.baseattrib.singActivation_jsp threw exception
java.lang.AbstractMethodError: javax.servlet.jsp.PageContext.getELContext()Ljavax/el/ELContext;
        at javax.servlet.jsp.jstl.core.LoopTagSupport.unExposeVariables(LoopTagSupport.java:587)
        at javax.servlet.jsp.jstl.core.LoopTagSupport.doFinally(LoopTagSupport.java:323)
        at org.apache.jsp.baseattrib.singActivation_jsp._jspService(singActivation_jsp.java:800)
        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.zte.web.FilterEconding.doFilter(FilterEconding.java:38)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
        at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
        at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
        at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
        at java.lang.Thread.run(Thread.java:595)
        
前段时间服务好好的，最近把工程合起来，出现上述问题，找了半天才找到问题原因，先把网上找到的方法统一列出来，希望能帮助大家（第一条是我遇到的问题，其余是网上的相关错误和解决办法）：
1、移出工程lib目录中的JSTL1.2.jar,添加standard-1.1.jar和JSTL1.1.jar
    jstl1.1版本由2个必要包构成：standard-1.1.jar和JSTL1.1.jar；而jstl1.2版本只有一个必要包JSTL1.2.jar；
    tomcat6.0支持JSTL1.2版本，也支持JSTL1.1版本；tomcat5.5只支持JSTL1.1；
    (原文：http://blog.csdn.net/ja_II_ck/article/details/4220102)
    而我大半天下来，发现把JSTL1.2.jar和JSTL1.1.jar都放到了服务器，导致问题发生，人为的错误，我要哭了~ ~
    

2、WebLogic 9.2 上部署的，错误提示：
    java.lang.NoSuchMethodError: javax/servlet/jsp/PageContext.getELContext()Ljavax/el/ELContext;
    at org.apache.taglibs.standard.tag.common.core.SetSupport.doEndTag(SetSupport.java:140)
    at jsp_servlet.__index._jsp__tag1(__index.java:206)
    at jsp_servlet.__index._jspService(__index.java:137)
    at weblogic.servlet.jsp.JspBase.service(JspBase.java:34)
    at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)
    Truncated. see log file for complete stacktrace
    
    解决方案：
    <%@ taglib uri="" prefix="c"%>
    <%@ taglib uri="" prefix="fmt"%>
    <%@ taglib uri="" prefix="fn"%>
    部署jstl-1.2.jar 包，在Tomcat 上部署 去掉el-api.jar 包，否则会报错；在WebLogic 9.2 上部署 加上el-api.jar 和 standard-1.0.2.jar；
    （原文：http://albert0707.iteye.com/blog/562969）