struts2拦截器

Struts2提供了强大的拦截器功能，特别是加上convention plugin之后，使用更方便：

配置拦截器：

<package name="my-default" extends="convention-default">
          <interceptors>
		<interceptor name="checkLogin" class="com.abc.interceptor.CheckLoginInterceptor"/>

		<interceptor-stack name="checkLoginstack">
                        <interceptor-ref name="checkLogin"></interceptor-ref>
                        <interceptor-ref name="defaultStack"></interceptor-ref><!--这里必须引用Struts2默认的拦截器defaultStack，否则会使传递的url参数丢失-->
                </interceptor-stack>
	</interceptors>

	<default-interceptor-ref name="my-default" />


</package>

  简单的拦截器

package com.abc.interceptor;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.AbstractInterceptor;

/**
 * 
 * @author Wilson
 *
 */
public class CheckLoginInterceptor extends AbstractInterceptor {

	private static final long serialVersionUID = 1L;
	

	@Override
	public String intercept(ActionInvocation invocation) throws Exception {
		......................
		String result = invocation.invoke();
		
		return result;
	}


}

 在action使用

@InterceptorRef("checkLoginstack")//全局引用拦截器
public class UserAction extends ActionSupport<Object> {
        ......

//局部引用拦截器,引用多个拦截器的话则是nterceptorRefs({@InterceptorRef("interceptor-1"),@InterceptorRef("interceptor-2")})
@Action(value = "/input", results = { @Result(name = "INPUT", location = "/input.jsp"),
			@Result(name = "login", location = "/login.jsp") },interceptorRefs = { @InterceptorRef("checkLoginstack") })
	public String input() throws Exception {
        ...........
    
        return "INPUT";
        }

}