Struts2访问 web 元素

struts2访问request、session、application对象：

一般是通过实现RequestAware、SessionAware、ApplicationAware接口实现的。

示例代码：

//只用这种方法

package com.demo.web;

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.ActionSupport;

public class LoginAction extends ActionSupport implements RequestAware, SessionAware, ApplicationAware {

private Map<String, Object> request;
private Map<String, Object> session;
private Map<String, Object> application;

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

}

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

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

public String execute() {
request.put("request", "request2");
session.put("session", "session2");
application.put("application", "application2");
return SUCCESS;
}

}

这种方式叫做 DI dependency injection

IoC inverse of control