JBPM4项目和tomcat6.0的兼容问题

冷不防 2022-09-30 09:56 113阅读 0赞

from:http://www.cnblogs.com/leshem/archive/2009/09/28/1575792.html

之前有遇到这个问题。当时没有记录下来怎么解决的。现在就又要来找了。记录下来备查。

我的方式是换到5.5了。第二个没有尝试。

**exception**

javax.servlet.ServletException: 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.jasper.servlet.JspServlet.service(JspServlet.java:275)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

**root cause**

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(juel.jar, juel-engine.jar, juel-impl.jar
    
    )和tomcat6下lib中jar包(el-api.jar
    
    )冲突

解决方法：

方法一：换成tomcat5.5 一点问题也没有了

方法二：将juel.jar, juel-engine.jar, juel-impl.jar
    
    这三个包复制到tomcat6下lib中，并删除原来的el-api.jar，切记要把WEB-INF/lib中的juel.jar, juel-engine.jar, juel-impl.jar删除。不然还是要冲突。