Struts2 Action访问web元素的四种方式

1： Map IoC  方式<最常用的方式>

package edu.uestc.test.action;

import java.util.Map;
import org.apache.struts2.interceptor.*;
import com.opensymphony.xwork2.ActionSupport;

public class UserAction1 extends ActionSupport implements RequestAware,SessionAware,ApplicationAware {
    private Map<String, Object> request;
    private Map<String, Object> session;
    private Map<String, Object> application;    
    public String add(){
        request.put("r1", "r1");
        session.put("s1", "s1");
        application.put("a1", "a1");
        return "success";
    }

    @Override
    public void setRequest(Map<String, Object> request) {
        this.request=request;        
    }

    @Override
    public void setSession(Map<String, Object> session) {
        this.session=session;        
    }

    @Override
    public void setApplication(Map<String, Object> application) {
        this.application=application;
    }
}

2： Map 依赖容器 方式:

package com.action;

import java.util.Map;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class UserAction2 extends ActionSupport {
    private Map<String, Object> request;
    private Map<String, Object> session;
    private Map<String, Object> application;    
    public UserAction2() {
        ActionContext context = ActionContext.getContext();
        request=(Map<String, Object>)context.get("request");
        session=context.getSession();
        application=context.getApplication();
    }
    public String add(){
        request.put("r2", "r2");
        session.put("s2", "s2");
        application.put("a2", "a2");
        return "success";
    }    
}

3： Servlet IoC  方式：

package com.action;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import org.apache.struts2.interceptor.ServletRequestAware;
import com.opensymphony.xwork2.ActionSupport;

public class UserAction3 extends ActionSupport implements ServletRequestAware {
    private HttpServletRequest request;
    private HttpSession session;
    private ServletContext application;
    public String add() {
        request.setAttribute("r3", "r3");
        session.setAttribute("s3", "s3");
        application.setAttribute("a3", "a3");
        return "success";
    }
    public void setServletRequest(HttpServletRequest request) {        
        this.request=request;
        this.session=request.getSession();
        this.application=session.getServletContext();
    }
}

4： Servlet 依赖容器  方式:

package edu.uestc.test.action;

import javax.servlet.ServletContext;
import javax.servlet.http.*;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class UserAction4 extends ActionSupport {
    private HttpServletRequest request;
    private HttpSession session;
    private ServletContext application;    
    public UserAction4() {
        request = ServletActionContext.getRequest();
        session=request.getSession();
        application=session.getServletContext();        
    }
    public String add(){
        request.setAttribute("r4", "r4");
        session.setAttribute("s4", "s4");
        application.setAttribute("a4", "a4");
        return "success";
    }    
}

原文链接：http://www.blogjava.net/yunjieyang/archive/2010/07/02/325023.html