Android端通过HttpURLConnection连接web服务器，通过post方法发送json数据，后台拿到json数据并解析

Android端通过HttpURLConnection连接web服务器，通过post方法发送json数据，后台拿到json数据并解析

1. Android端
   （1）布局文件

（2）MainActivity.java

package com.example.logindemo;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.ProtocolException;
import java.net.URL;

public class MainActivity extends AppCompatActivity {
    EditText account;
    EditText password;
    EditText name;
    public TextView textView;
    Button login;

    org.json.JSONObject userInfo = new JSONObject();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        account=(EditText)findViewById(R.id.account);//输入账户
        password=(EditText)findViewById(R.id.password);//输入密码
        name=(EditText)findViewById(R.id.name);//输入密码
        textView=(TextView)findViewById(R.id.text);
        login=(Button)findViewById(R.id.login);

        /**
         * 登录逻辑
         * 将输入的账号和密码获取
         * 判断是否为空
         *
         */

//        final User user=new User();
//        user.setUserName("张三");
//        user.setUserPassword(password.getText().toString());
//        user.setUserPhone("1836666666");

        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                User user=new User();
                user.setUserPhone(account.getText().toString());
                user.setUserPassword(password.getText().toString());
                user.setUserName(name.getText().toString());
                if (!(account.getText().toString().isEmpty())
                        && !(password.getText().toString().isEmpty())) {
                    loginPost(user);
                } else {
                    Toast.makeText(MainActivity.this, "账号、密码都不能为空！", Toast.LENGTH_SHORT).show();
                }
            }

        });
    }

    public void loginPost(User user){
        String name=user.getUserName();
        String password=user.getUserPassword();
        String phone=user.getUserPhone();
        /**
         * 192.168.0.100为电脑ipv4地址
         * Demo_Database为eclipse中的工程名
         * TestServlet为要提交到的servlet名
         */
        String path="http://192.168.0.100:8080/Demo_Database/TestServlet";
        new MyPostTask().execute(name,password,phone,path);//调方法
    }

    class MyPostTask extends AsyncTask{
        @Override
        protected String doInBackground(String...  params) {
            String name=params[0];
            String password=params[1];
            String phone=params[2];
            String path=params[3];
            HttpURLConnection conn=null;

            JSONObject userJSON = new JSONObject();
            try {
                userJSON.put("name",name);
                userJSON.put("password",password);
                userJSON.put("phone",phone);
                String content = String.valueOf(userJSON);

            try {
                URL url=new URL(path);
                conn= (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("POST");
                conn.setConnectTimeout(8000);//超时时间
                /**
                 * conn.setRequestProperty("Content-Length",s.length()+"");
                 * 这条语句可能会导致报java.net.ProtocolException: exceeded content-length limit of 26 bytes 错误
                 */
//              conn.setRequestProperty("Content-Length",s.length()+"");
                conn.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
                conn.setDoOutput(true);//允许对外输出数据
                conn.setDoInput(true);
                OutputStream os=conn.getOutputStream();//写数据OutputStream
                os.write(content.getBytes());//把数据传递给服务器了
                os.flush();
                os.close();
                Log.d("code","code"+conn.getResponseCode());

                System.out.println(conn.getResponseCode());

                if(conn.getResponseCode()==200){//拿到返回结果
                    InputStream is=conn.getInputStream();
                    BufferedReader br=new BufferedReader(new InputStreamReader(is));
                    String str=br.readLine();
                    return str;
                }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (ProtocolException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

            } catch (JSONException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(String s) {
            Log.d("JSON",s);//打印服务器返回标签
            //flag=true;
            switch (s){
                //判断返回的状态码，并把对应的说明显示在UI
                case "100":
                    textView.setText(s+"：登录失败，密码不匹配或账号未注册");
                    break;
                case "200":
                    textView.setText(s+"：登录成功");
                    break;
                default:
                    textView.setText("异常");
            }
            Log.d("JSON","验证后");
        }
    }
}

（3）AndroidManifest.xml文件

（4）User.java

package com.example.logindemo;

public class User {

	public String getUserPhone() {
		return userPhone;
	}

	public void setUserPhone(String userPhone) {
		this.userPhone = userPhone;
	}

	public String getUserName() {
		return userName;
	}

	public void setUserName(String userName) {
		this.userName = userName;
	}

	public String getUserPassword() {
		return userPassword;
	}

	public void setUserPassword(String userPassword) {
		this.userPassword = userPassword;
	}

	private String userPhone;//手机号码
	private String userName;//昵称
	private String userPassword;//密码

	public User(){

	}
}

2. web服务器端
   （1）eclipse中新建名为Demo_Database的web工程
   （2）TestServlet

package Demo_Database;

import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.alibaba.fastjson.JSON;

import net.sf.json.JSONObject;

/**
 * Servlet implementation class TestServlet
 */
@WebServlet("/TestServlet")
public class TestServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public TestServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

		int code = 200;  
		  
		String streamIn = inputStreamToString(new BufferedInputStream(request.getInputStream())); 
		System.out.println(streamIn);
		JSONObject object = JSONObject.fromObject(streamIn);
		object.put("userJSON",streamIn );
        JSONObject userInfo = JSONObject.fromObject(object.getString("userJSON"));     
	    String name=userInfo.getString("name");
	    String password=userInfo.getString("password"); 
	    String phone=userInfo.getString("phone"); 
	    System.out.println(name+"  "+password+"     "+phone);
        response.setContentType("text/html;charset=utf-8"); // 设置响应报文的编码格式
//         
//      PrintWriter out = response.getWriter();
//      out.write("成功");
//		out.close();
	    PrintWriter out = response.getWriter();
	    String json=JSON.toJSONString(code);
	    out.println(json);		
		out.flush();
		out.close();
	}
	public String inputStreamToString(InputStream inputStream) throws IOException {
        int len = 0;
        byte[] butter = new byte[1024];
        StringBuffer stringBuffer = new StringBuffer();
        while ((len = inputStream.read(butter)) != -1) {
            String s = new String(butter, 0, len, "UTF-8");
            stringBuffer.append(s);
        }
        return stringBuffer.toString();
    }
}

（3）jar包
commons-beanutils-1.9.2.jar
commons-collections-3.2.1.jar
commons-lang-2.4.jar
commons-logging-1.1.1.jar
ezmorph-1.0.6.jar
fastjson-1.2.22.jar
json-lib-2.4-jdk15.jar