at org.apache.struts.action.ActionServlet.parseModuleConfigFile错误的解决方法

tomcat 启动后，报出了如下异常

java.lang.NullPointerException at org.apache.struts.action.ActionServlet.parseModuleConfigFile(ActionServlet.java:1003)，

 

2010-05-17 16:09:14,031[ ApplicationContext.java:676:ERROR] StandardWrapper.Throwable
java.lang.NullPointerException
	at org.apache.struts.action.ActionServlet.parseModuleConfigFile(ActionServlet.java:1003)
	at org.apache.struts.action.ActionServlet.initModuleConfig(ActionServlet.java:955)
	at org.apache.struts.action.ActionServlet.init(ActionServlet.java:470)
	at cn.ac.iscas.core.control.LocalActionServlet.init(LocalActionServlet.java:124)
	at javax.servlet.GenericServlet.init(GenericServlet.java:212)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1139)
	at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:966)
	at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3956)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4230)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
	at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:626)
	at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:553)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:488)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1149)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:448)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)
2010-05-17 16:09:14,047[    StandardContext.java:3958:ERROR] Servlet /pm threw load() exception
java.lang.NullPointerException
	at org.apache.struts.action.ActionServlet.parseModuleConfigFile(ActionServlet.java:1003)
	at org.apache.struts.action.ActionServlet.initModuleConfig(ActionServlet.java:955)
	at org.apache.struts.action.ActionServlet.init(ActionServlet.java:470)
	at cn.ac.iscas.core.control.LocalActionServlet.init(LocalActionServlet.java:124)
	at javax.servlet.GenericServlet.init(GenericServlet.java:212)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1139)
	at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:966)
	at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3956)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4230)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
	at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:626)
	at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:553)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:488)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1149)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:448)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)

 

在网上查了半天，说什么的都有，具体到自己的项目，错误的原因是下面的：

 

在我的项目的 web.xml中，有关config的配置是：

 

    <init-param> 
      <param-name>config</param-name>  
      <param-value>/WEB-INF/struts-config-hl.xml,/WEB-INF/struts-config.xml,/WEB-INF/struts-config-pm.xml,/WEB-INF/struts-config-spa.xml,/WEB-INF/struts-config-mt.xml,/WEB-INF/struts-config-org.xml,/WEB-INF/struts-config-scm.xml,/WEB-INF/struts-config-rm.xml,/WEB-INF/struts-config-dataview.xml,/WEB-INF/struts-config-cus.xml,/WEB-INF/struts-config-scmt.xml</param-value> 
    </init-param> 

 

但是在更新代码的时候，恰巧没有把WEB-INF/struts-config-scmt.xml这个文件给更新下来，所以一直报上述错误。

 

 

错误查询步骤，在我的项目中，使用了struts1.1，其中的ActionServlet类中parseModuleConfigFile方法是： 

 

 private void parseModuleConfigFile(
        String prefix,
        String paths,
        ModuleConfig config,
        Digester digester,
        String path)
        throws UnavailableException {

        InputStream input = null;
        try {
            URL url = getServletContext().getResource(path);
            InputSource is = new InputSource(url.toExternalForm());
            input = getServletContext().getResourceAsStream(path);
            is.setByteStream(input);
            digester.parse(is);
            getServletContext().setAttribute(Globals.MODULE_KEY + prefix, config);
            
        } catch (MalformedURLException e) {
            handleConfigException(paths, e);
        } catch (IOException e) {
            handleConfigException(paths, e);
        } catch (SAXException e) {
            handleConfigException(paths, e);
        } finally {
            if (input != null) {
                try {
                    input.close();
                } catch (IOException e) {
                    throw new UnavailableException(e.getMessage());
                }
            }
        }
    }

 

 第1003行就是

 URL url = getServletContext().getResource(path);

也就是说在查找配置文件的过程中，有一个path找不多对应的资源文件；

 

然后在web.xml的config字段中，挨个检查配置文件，发现找不到 /WEB-INF/struts-config-scmt.xml 对应的源文件，于是找到出错原因。