Struts2访问request，session，application的四种方式

  方式1--》访问Map类型的：

package cn.pdsu.edu;
import java.util.Map;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

/**
 * 普通方式：Map类型的request,session,application
 */
public class ActionDemo1 extends ActionSupport {
    private Map request;
    private Map session;
    private Map application;
   
    public ActionDemo1() {
        this.request = (Map)ActionContext.getContext().get("request");
        this.session = ActionContext.getContext().getSession();
        this.application = ActionContext.getContext().getApplication();
    }

    @Override
    public String execute() throws Exception {
        request.put("message", "message");
        session.put("message", "message");
        application.put("message", "message");
        return SUCCESS;
    }
}

方式2--》访问map类型的：

package cn.pdsu.edu;
import java.util.Map;

import org.apache.struts2.interceptor.ApplicationAware;
import org.apache.struts2.interceptor.RequestAware;
import org.apache.struts2.interceptor.SessionAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

/**
 *接口方式：Map类型的request,session,application
 */
public class ActionDemo2 extends ActionSupport implements RequestAware,SessionAware,ApplicationAware{
    private Map request;
    private Map session;
    private Map application;

    @Override
    public String execute() throws Exception {
        request.put("message", "message");
        session.put("message", "message");
        application.put("message", "message");
        return SUCCESS;
    }

    public void setRequest(Map request) {
        this.request=request;
    }

    public void setSession(Map session) {
        this.session=session;
    }

    public void setApplication(Map application) {
        this.application = application;
    }
}
方式3--》访问HttpServletRequest

package cn.pdsu.edu;
import java.util.Map;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext;
import org.apache.struts2.interceptor.ApplicationAware;
import org.apache.struts2.interceptor.RequestAware;
import org.apache.struts2.interceptor.SessionAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

/**
 * 普通方式：Servlet类型的request,session,application
 */
public class ActionDemo3 extends ActionSupport {
    private HttpServletRequest request;
    private HttpSession session;
    private ServletContext application;

    public ActionDemo3() {
        request = ServletActionContext.getRequest();
        session = request.getSession();
        application = session.getServletContext();
    }

    @Override
    public String execute() throws Exception {
        request.setAttribute("message", "message");
        session.setAttribute("message", "message");
        application.setAttribute("message", "message");
        return SUCCESS;
    }
}
方式4--》通过接口访问HttpServletRequest

package cn.pdsu.edu;
import java.util.Map;

import javax.management.j2ee.statistics.ServletStats;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext;
import org.apache.struts2.interceptor.ApplicationAware;
import org.apache.struts2.interceptor.RequestAware;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.SessionAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

/**
 * 接口方式：Servlet类型的request,session,application
 */
public class ActionDemo4 extends ActionSupport implements ServletRequestAware{
    private HttpServletRequest request;
    private HttpSession session;
    private ServletContext application;

    @Override
    public String execute() throws Exception {
        request.setAttribute("message", "message");
        session.setAttribute("message", "message");
        application.setAttribute("message", "message");
        return SUCCESS;
    }

    public void setServletRequest(HttpServletRequest request) {
        this.request = request;
        this.session = request.getSession();
        this.application = session.getServletContext();
    }
}