tomcat6下布署网站的一点小问题

将原来tomcat5.5.29上的网站部署到tomcat6.0.32是，有时会因为el的jar包冲突导致无法运行：

出错信息类似：

java.lang.LinkageError: loader constraint violation: when resolving interface method "javax.servlet.jsp.JspApplicationContext.getExpressionFactory()Ljavax/el/ExpressionFactory;" the class loader (instance of org/apache/jasper/servlet/JasperLoader) of the current class, org/apache/jsp/OnDuty/wfmanage_jsp, and the class loader (instance of org/apache/catalina/loader/StandardClassLoader) for resolved class, javax/servlet/jsp/JspApplicationContext, have different Class objects for the type javax/el/ExpressionFactory used in the signature
	org.apache.jsp.OnDuty.wfmanage_jsp._jspInit(wfmanage_jsp.java:27)
	org.apache.jasper.runtime.HttpJspBase.init(HttpJspBase.java:52)
	org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:159)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:329)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

 

原因是项目中WEB-INF\lib中的三个jar包(el-api-1.0.jar
juel-api-2.1.2.jar
juel-impl-2.1.2.jar
)和tomcat6下lib中jar包(el-api.jar)冲突

解决方法：删除el-api-1.0.jar
juel-api-2.1.2.jar
juel-impl-2.1.2.jar

el 统一用tomcat6/lib下的。