创建自己struts2拦截器
步骤：
1：创建一个类实现com.opensymphony.xwork2.interceptor.Interceptor接口
2：实现intercept(ActionInvocation invocation) 方法
3：在struts.xml中配置拦截器
4： 链接到相应的action
代码下载
文件目录：
struts2自身有很多的拦截器，在struts-core.jar中的struts-default.xml中。
首先创建一个HelloAction
package com.topwqp.common.action;
import com.opensymphony.xwork2.ActionSupport;
public class HelloAction extends ActionSupport {
public String execute() throws Exception {
System.out.println("HelloAction execute() is called");
return SUCCESS;
}
}
然后创建相应拦截器：
init()方法是在启动服务器时加载拦截器时初始化的
destory()方法是在退出服务器调用的，但是这个方法不一定调用
ActionInvocation也是一个接口，对应Action或者其他的拦截器
解释：
An ActionInvocation represents the execution state of an Action. It holds the Interceptors and the Action instance. By repeated re-entrant execution of the invoke() method, initially by the ActionProxy, then by the Interceptors, the Interceptors are all executed, and then the Action and the Result.关于invoke()方法是必须的：
invoke
String invoke()
throws Exception
Invokes the next step in processing this ActionInvocation.
If there are more Interceptors, this will call the next one. If Interceptors choose not to short-circuit ActionInvocation processing and return their own return code, they will call invoke() to allow the next Interceptor to execute. If there are no more Interceptors to be applied, the Action is executed. If the ActionProxy.getExecuteResult() method returns true, the Result is also executed.
Returns:
the return code.
Throws:
Exception - can be thrown.
package com.topwqp.common.interceptor;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;
public class PrintMessageInterceptor implements Interceptor{
@Override
public void destroy() {
// TODO Auto-generated method stub
System.out.println("destory() method is invoked");
}
@Override
public void init() {
// TODO Auto-generated method stub
System.out.println("init() method is invoked");
}
//put interceptor code here
@Override
public String intercept(ActionInvocation invocation) throws Exception {
// TODO Auto-generated method stub
System.out.println("before invocation.invoked..........");
String result = invocation.invoke();
System.out.println(result);
System.out.println("after invocation.invoked..........");
return result;
}
}
对应的struts.xml配置：
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<package name="default" namespace="/" extends="struts-default">
<interceptors>
<interceptor name="printMessageInterceptor"
class="com.topwqp.common.interceptor.PrintMessageInterceptor">
</interceptor>
<interceptor-stack name="newStack">
<interceptor-ref name="printMessageInterceptor"/>
<interceptor-ref name="defaultStack"/>
</interceptor-stack>
</interceptors>
<action name="helloAction"
class="com.topwqp.common.action.HelloAction" >
<interceptor-ref name="newStack"/>
<result name="success">pages/hello.jsp</result>
</action>
</package>
</struts>
对应的hello.jsp配置：
<html> <body> <h2>Hello TOPWQP</h2> </body> </html>
启动访问： 路径：http://localhost:8080/Strut2OwnInterceptor/helloAction
结果：
五月 05, 2013 4:16:29 下午 org.apache.catalina.core.AprLifecycleListener init INFO: Loaded APR based Apache Tomcat Native library 1.1.24. 五月 05, 2013 4:16:30 下午 org.apache.catalina.core.AprLifecycleListener init INFO: APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true]. 五月 05, 2013 4:16:32 下午 org.apache.tomcat.util.digester.SetPropertiesRule begin WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.j2ee.server:Strut2OwnInterceptor' did not find a matching property. 五月 05, 2013 4:16:38 下午 org.apache.coyote.http11.Http11AprProtocol init INFO: Initializing Coyote HTTP/1.1 on http-8080 五月 05, 2013 4:16:38 下午 org.apache.coyote.ajp.AjpAprProtocol init INFO: Initializing Coyote AJP/1.3 on ajp-8009 五月 05, 2013 4:16:38 下午 org.apache.catalina.startup.Catalina load INFO: Initialization processed in 13193 ms 五月 05, 2013 4:16:38 下午 org.apache.catalina.core.StandardService start INFO: Starting service Catalina 五月 05, 2013 4:16:38 下午 org.apache.catalina.core.StandardEngine start INFO: Starting Servlet Engine: Apache Tomcat/6.0.35 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Parsing configuration file [struts-default.xml] 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Unable to locate configuration files of the name struts-plugin.xml, skipping 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Parsing configuration file [struts-plugin.xml] 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Parsing configuration file [struts.xml] 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for class com.opensymphony.xwork2.ObjectFactory 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for class com.opensymphony.xwork2.conversion.impl.XWorkConverter 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.TextProvider 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.ActionProxyFactory 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.conversion.ObjectTypeDeterminer 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface org.apache.struts2.dispatcher.mapper.ActionMapper 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (jakarta) for interface org.apache.struts2.dispatcher.multipart.MultiPartRequest 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for class org.apache.struts2.views.freemarker.FreemarkerManager 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface org.apache.struts2.components.UrlRenderer 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.validator.ActionValidatorManager 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.util.ValueStackFactory 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.util.reflection.ReflectionProvider 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.util.reflection.ReflectionContextFactory 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.util.PatternMatcher 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface org.apache.struts2.dispatcher.StaticContentLoader 五月 05, 2013 4:16:43 下午 com.opensymphony.xwork2.util.logging.jdk.JdkLogger info INFO: Choosing bean (struts) for interface com.opensymphony.xwork2.UnknownHandlerManager init() method is invoked 五月 05, 2013 4:16:44 下午 org.apache.coyote.http11.Http11AprProtocol start INFO: Starting Coyote HTTP/1.1 on http-8080 五月 05, 2013 4:16:45 下午 org.apache.coyote.ajp.AjpAprProtocol start INFO: Starting Coyote AJP/1.3 on ajp-8009 五月 05, 2013 4:16:45 下午 org.apache.catalina.startup.Catalina start INFO: Server startup in 7060 ms before invocation.invoked.......... HelloAction execute() is called success after invocation.invoked..........