此文只是用了GET方法请求，所有POST方法没有贴出来了，下次使用另外更新。
对应接口是本人的本地服务器，所以别人无法访问，此文主要记录接口的写法以及细节。

字符编码

//设置UTF-8编码
response.setContentType("text/html; charset=UTF-8");
//中文字符转译
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("uth-8");

登录

login1：http://192.168.1.101:8080/myweb/servlet/myservlet?name=rr&password=123
login2：http://192.168.2.100:8080/myweb/servlet/myservlet?name=rr&password=123

//登录接口实现方法
public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
    response.setContentType("text/html; charset=UTF-8");
    PrintWriter out = response.getWriter();
    //字符转译
    request.setCharacterEncoding("utf-8");
    response.setCharacterEncoding("uth-8");
    //获取name参数的值
    String name = request.getParameter("name").toString();
    //获取password参数的值
    String password = request.getParameter("password").toString();
    //判断
    if (name.equals("rr") && password.equals("123")) {
        returnmsg(out, 1, "登录成功!");
    } else {
        System.out.println(name + password);
        returnmsg(out, 2, "登录失败,用户名或密码错误!");
    }
}
/**
 * 返回参数
 * @param out
 * @param code
 * @param message
 * @throws UnsupportedEncodingException 
 */
public void returnmsg(PrintWriter out, int code, String message) {
    Map<String, Object> msg = new HashMap<String, Object>();
    msg.put("code", code);
    msg.put("msg", message);
    //转为json格式，先要导入gson包
    out.print(new Gson().toJson(msg));
}

返回结果：

{
    "code":1,
    "msg":"登录成功"
}

用户列表

adminList1：http://192.168.1.101:8080/myweb/servlet/adminlist
adminList2：http://192.168.2.100:8080/myweb/servlet/adminlist

public class adminlist extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //UTF-8
        response.setContentType("text/html; charset=UTF-8");
        //字符转译
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("uth-8");
        PrintWriter out = response.getWriter();
        out.print(returnAdminlist());
    }
    /**
     *  将生成的数据抽成一个方法，并返回生成的数据
     */
    public List<String> returnAdminlist() {
        List<String> mapList = new ArrayList<String>();
        List<String> address = new ArrayList<String>();
        address.add("杭州");
        address.add("北京");
        address.add("深圳");
        address.add("上海");
        address.add("耒阳");
        for (int i = 0; i < 10; i++) {
            Map< String, String> adminlist = new HashMap<String, String>();
            adminlist.put("admin", "小荣儿" + (i + 1));
            adminlist.put("address", address.get(new Random().nextInt(5)));
            adminlist.put("tel", randomNum());
            mapList.add(new Gson().toJson(adminlist));
        }
        return mapList;
    }
    /**
     *  随机生成一个9以内的数字，并拼凑成10位数字
     */
    public String randomNum() {
        String randString = "";
        for (int i = 0; i < 10; i++) {
            Random random = new Random();
            randString += random.nextInt(9);
        }
        return "1" + randString;
    }
}

返回结果：

[
    {
        "address":"深圳",
        "admin":"小荣儿1",
        "tel":"14178070375"
    }, 
    {
        "address":"北京",
        "admin":"小荣儿2",
        "tel":"18828271185"
    }
    .....
]