>

<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

<!-- 定义Struts2的核心控制器：FilterDispatcher -->
<filter>
<!-- 定义核心Filter的名称 -->
<filter-name>struts2</filter-name>
<!-- 定义Filter的实现类 -->
<filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
</filter>

<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>

</web-app>

<!-- setting encoding,DynamicMethod,language
<constant name="struts.custom.i18n.resources" value="messageResource"></constant>
-->
<constant name="struts.i18n.encoding" value="UTF-8"></constant>
<constant name="struts.enable.DynamicMethodInvocation" value="true"></constant>

<!-- add package here extends="struts-default"-->
<package name="dongzi" extends="json-default"> <!--须要将struts-default改为json-default-->
<!-- setting action -->
<action name="login" class="com.dongzi.action.loginAction" method="login">
<result type="json"></result> <!--返回值类型设置为json,不设置返回页面-->
</action>
</package>
</struts>

HttpServletRequest request;
HttpServletResponse response;

public void setServletRequest(HttpServletRequest request) {
this.request=request;
}

public void setServletResponse(HttpServletResponse response) {
this.response=response;
}

public void login(){
try {
//HttpServletRequest request =ServletActionContext.getRequest();
// HttpServletResponse response=ServletActionContext.getResponse();
this.response.setContentType("text/html;charset=utf-8");
this.response.setCharacterEncoding("UTF-8");
if(this.request.getParameter("username").equals("123456")){
this.response.getWriter().write("真的非常奇怪,日本人！");
}else if(this.request.getParameter("username").equals("zhd")){
this.response.getWriter().write("没有错，我就是东子哥！");
}else{
this.response.getWriter().write("我就是东子哥！");
}

//将要返回的实体对象进行json处理
// JSONObject json=JSONObject.fromObject(this.getUsername());
//输出格式如：{"id":1, "username":"zhangsan", "pwd":"123"}
// System.out.println(json);

// this.response.getWriter().write(json.toString());
/**
JSONObject json=new JSONObject();
json.put("login", "login");
response.setContentType("text/html;charset=utf-8");
System.out.println(json);
byte[] jsonBytes = json.toString().getBytes("utf-8");
response.setContentLength(jsonBytes.length);
response.getOutputStream().write(jsonBytes);
**/
/**
JSONObject json=new JSONObject();
json.put("login", "login");
byte[] jsonBytes = json.toString().getBytes("utf-8");
response.setContentType("text/html;charset=utf-8");
response.setContentLength(jsonBytes.length);
response.getOutputStream().write(jsonBytes);
response.getOutputStream().flush();
response.getOutputStream().close();
**/

} catch (Exception e) {
e.printStackTrace();
}
// return null;
}
}