前言：作为一名android开发人员，网络数据都是web开发人员提供，每次让他们写一个接口都跟求神拜佛一样，与其求别人还不如自己动手.......（千万只羊驼从天空飞过）总算研究出来了，写下来有的人可能会用到。也算是自己做个笔记。
项目使用MyEclipse+Struts+Tomcat搭建的 ，这三个从网站下载即可，Tomcat需要配置，网上这类的文章很多，这里不再介绍。

配置Struts

下载下来后，解压，找到这两个目录

MyEclipse2.png

MyEclipse3.png

MyEclipse新建工程

File->New->WebProject 选择Next即可，记得把这个勾上（减少麻烦）

MyEclipse1.png

新建完工程后，把刚才复制的两个分别放到这两个地方，对应放进去（struts.xml有错误，等会再修改配置，不用着急）

MyEclipse4.png

新建两个包，UserAction和User两个类

MyEclipse5.png

public class UserAction extends ActionSupport{
    
    private String username;
    private String password;
    private HttpServletResponse response;
    private User model;
    
    public String login() throws Exception{
        
        System.out.println(username+","+password);
         response=ServletActionContext.getResponse();
          response.setContentType("application/json");
          Gson gson = new Gson();
          String str = gson.toJson(getContent());
        PrintWriter writer=response.getWriter();
        writer.write(str);
     
        return null;
    }
    
    private User getContent(){
        model=new User();
        model.setName("Android");
        model.setAge("100");
        model.setSex("Male");
        return model;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
}

public class User {
private String name;
private String sex;
private String age;
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getSex() {
    return sex;
}
public void setSex(String sex) {
    this.sex = sex;
}
public String getAge() {
    return age;
}
public void setAge(String age) {
    this.age = age;
}
}

下面修改Struts.xml里面的错误

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>

    <constant name="struts.enable.DynamicMethodInvocation" value="true" />
    <constant name="struts.devMode" value="true" />

    <package name="default" namespace="/" extends="struts-default">

        <action name="login" class="com.server.action.UserAction" method="login"></action>
    </package>
//name 随便起
//class 对应的包名+类一定要对应起来（按住ctrl点击看看能不能跳转过去，判断写的对不对）
//method login对应的是UserAction里的login()方法
  
</struts>

最后修改WebRoot->WEB-INF-web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>myServer</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  添加filter和filter-mapping配置struts2
   <filter>
        <filter-name>struts2</filter-name>
        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
    </filter>

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

最后，启动Tomcat，如果这个没有Servers这个栏目，点击Window->ShowView->Servers添加

MyEclipse6.png

右键启动Tomcat

MyEclipse7.png

Android端来解析

OkHttpClient mOkhttpClient = new OkHttpClient();
        final Request request = new Request.Builder().url(URL + "login?username=wangwei&password=666666").build();
        Call call = mOkhttpClient.newCall(request);
        call.enqueue(new Callback() {
            @Override
            public void onFailure(Request request, IOException e) {

            }

            @Override
            public void onResponse(Response response) throws IOException {
                String res = response.body().string();
                Log.e("tag", "return ===" + res);
                try {
                    JSONObject jsonObject=new JSONObject(res);
                    String name=jsonObject.optString("name");
                    String sex=jsonObject.optString("sex");
                    String age=jsonObject.optString("age");
                    Log.e("tag","name==="+name+",age==="+age+",sex==="+sex);
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        });