struts2访问session的两种方法（转载）

Struts2 的Action中若希望访问Session对象，可采用两种方式：

1、从ActionContext中获取；

2、实现SessionAware接口。

 

1、从ActionContext中获取：

import java.util.Map;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class SessionTestAction extends ActionSupport {
    public String execute() {
     ActionContext actionContext = ActionContext.getContext();
       Map session = actionContext.getSession();
       session.put("USER_NAME", "Test User");
       return SUCCESS;
    }
}

import java.util.Map; import com.opensymphony.xwork2.ActionContext; import com.opensymphony.xwork2.ActionSupport; public class SessionTestAction extends ActionSupport { public String execute() { ActionContext actionContext = ActionContext.getContext(); Map session = actionContext.getSession(); session.put("USER_NAME", "Test User"); return SUCCESS; } }

 

2、实现SessionAware接口：

import java.util.Map;
import org.apache.struts2.interceptor.SessionAware;
import com.opensymphony.xwork2.ActionSupport;
public class SessionTest1Action extends ActionSupport implements SessionAware {
    private Map session;
    public void setSession(Map session) {
       this.session = session;
    }
    public String execute() {
       this.session.put("USER_NAME", "Test User 1");
       return SUCCESS;
    }
}

import java.util.Map; import org.apache.struts2.interceptor.SessionAware; import com.opensymphony.xwork2.ActionSupport; public class SessionTest1Action extends ActionSupport implements SessionAware { private Map session; public void setSession(Map session) { this.session = session; } public String execute() { this.session.put("USER_NAME", "Test User 1"); return SUCCESS; } } 

 

进一步阅读Struts2.1.8.1源码，SessionAware接口的实现方式如下：

 

struts-default.xml配置：

<interceptors>
  ...
  <interceptor name="servletConfig" class="org.apache.struts2.interceptor.ServletConfigInterceptor"/>
  ...
interceptors>
<interceptor-stack name="defaultStack">
  ...
  <interceptor-ref name="servletConfig"/>
  ...
interceptor-stack>

... ... ... ...  

 

打开ServletConfigInterceptor.java源码：

public String intercept(ActionInvocation invocation) throws Exception {
    final Object action = invocation.getAction();
    final ActionContext context = invocation.getInvocationContext();

    ...
    if (action instanceof SessionAware) {
        ((SessionAware) action).setSession(context.getSession());
    }
    ...
    return invocation.invoke();
}

public String intercept(ActionInvocation invocation) throws Exception { final Object action = invocation.getAction(); final ActionContext context = invocation.getInvocationContext(); ... if (action instanceof SessionAware) { ((SessionAware) action).setSession(context.getSession()); } ... return invocation.invoke(); }

即在拦截器处理过程中发现目标Action实现了SessionAware接口，便会调用Action中已经实现的setSession(...) 方法，将ActionContext中包装的Session注入目标Action中。目标Action也就可以进一步对Session进行操作了。

转载 http://blog.csdn.net/puffCN/article/details/5607557