android之向服务器提交数据（GET,POST,AsyncHttpClient）

1.首先我们先用Eclipse创建一个简单的服务器

其login.jsp的代码如下：

登录界面



	用户名：

	密码：

	

loginServlet.java的代码如下：

package work0727;

import java.io.IOException;
import java.io.PrintWriter;

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

/**
*@author 尹丹
*@data 2017年7月27日
*
*/

public class LoginServlet extends HttpServlet{
	
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		
		//获取用户名和密码
		String uname=req.getParameter("uname");
		String upass=req.getParameter("upass");
		System.out.println(uname+" "+upass);
		
		String result=null;
		if ("admin".equals(uname)&&"123".equals(upass)) {
			result="seccess";
		}else{
			result="file";
		}
		PrintWriter pw=resp.getWriter();
		pw.write(result);
		pw.close();
		
		
	}

}

配置的代码如下：

  
  	loginServlet
  	work0727.LoginServlet
  
  
  
  	loginServlet
    /login.do
  

2.新建一个安卓项目

xml布局代码如下：

java代码如下：

package com.example.cookie.android0727commitdata;

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

import com.loopj.android.http.AsyncHttpClient;
import com.loopj.android.http.RequestParams;
import com.loopj.android.http.TextHttpResponseHandler;

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.URL;

public class MainActivity extends AppCompatActivity {

    private EditText et_main_uname;
    private EditText et_main_upass;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et_main_uname = (EditText) findViewById(R.id.et_main_uname);
        et_main_upass = (EditText) findViewById(R.id.et_main_upass);
    }

    public void loginAsyncHttpClient(View view){
        String uname=et_main_uname.getText().toString();
        String upass=et_main_upass.getText().toString();
        String path="http://192.168.32.103:8080/work0727/login.do";
        AsyncHttpClient ahc=new AsyncHttpClient();
        RequestParams paarms=new RequestParams();
        paarms.put("uname",uname);
        paarms.put("upass",upass);
        ahc.post(this,path,paarms,new TextHttpResponseHandler(){
            @Override
            public void onFailure(int statusCode, org.apache.http.Header[] headers, String responseBody, Throwable error) {
                super.onFailure(statusCode, headers, responseBody, error);
            }

            @Override
            public void onSuccess(int statusCode, org.apache.http.Header[] headers, String responseBody) {
                super.onSuccess(statusCode, headers, responseBody);
                Toast.makeText(MainActivity.this, responseBody, Toast.LENGTH_SHORT).show();
            }
        });
    }


    public void loginPost(View view){
        String uname=et_main_uname.getText().toString();
        String upass=et_main_upass.getText().toString();
        String path="http://192.168.32.103:8080/work0727/login.do";
        new MyPostTask().execute(uname,upass,path);
    }

    class MyPostTask extends AsyncTask{

        @Override
        protected Object doInBackground(Object[] params) {
            String uname=params[0].toString();
            String upass=params[1].toString();
            String path=params[2].toString();
            try {
                URL url=new URL(path+"");
                HttpURLConnection connection= (HttpURLConnection) url.openConnection();
                connection.setRequestMethod("POST");
                connection.setConnectTimeout(5000);

                String s="uname"+uname+"&upass"+upass;
                //添加请求头
                connection.setRequestProperty("Content-Length",s.length()+"");
                connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded");

                connection.setDoOutput(true);//允许对外输出数据
                OutputStream os=connection.getOutputStream();
                os.write(s.getBytes());

                if (connection.getResponseCode()==200){
                    InputStream is=connection.getInputStream();
                    //is 要么是seccess 要么是fail
                    BufferedReader br=new BufferedReader(new InputStreamReader(is));
                    String str=br.readLine();
                    return s;
                }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(Object o) {

            String s= (String) o;
            Toast.makeText(MainActivity.this, s+"", Toast.LENGTH_SHORT).show();

            super.onPostExecute(o);
        }
    }

    public void loginGet(View view){
        String uname=et_main_uname.getText().toString();
        String upass=et_main_upass.getText().toString();
        String path="http://192.168.32.103:8080/work0727/login.do";
        new MyGetTask().execute(uname,upass,path);
    }

    class MyGetTask extends AsyncTask{

        @Override
        protected Object doInBackground(Object[] params) {
            //主要是获取数据
            String uname=params[0].toString();
            String upass=params[1].toString();
            String path=params[2].toString();

            try {
                URL url=new URL(path+"?uname="+uname+"&upass="+upass);
                HttpURLConnection connection= (HttpURLConnection) url.openConnection();
                connection.setRequestMethod("GET");
                connection.setConnectTimeout(5000);
                if (connection.getResponseCode()==200){
                    InputStream is=connection.getInputStream();
                    //is 要么是seccess 要么是fail
                    BufferedReader br=new BufferedReader(new InputStreamReader(is));
                    String s=br.readLine();
                    return s;
                }
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(Object o) {
            String s= (String) o;
            Toast.makeText(MainActivity.this, ""+s, Toast.LENGTH_SHORT).show();

            super.onPostExecute(o);
        }
    }
}

注意：用AsyncHttpClient提交数据时是需要导入.Jar包的，将android-async-http-1.4.4.jar放到Project的该项目的libs文件夹下面。

再在build.gradle文件下的android后面的花括号里面添加一行这样的代码

useLibrary 'org.apache.http.legacy'

再重新编译一下。