与服务器进行数据Android--->servlet（get、post、AsyncClient）三种方式

Android端：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"    android:orientation="vertical"    android:layout_height="match_parent">    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="请输入用户名"        android:id="@+id/et_main_uname"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="请输入密码"        android:id="@+id/et_main_upass"        />    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="登录(GET)"        android:onClick="loginGet"        /><Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="登录(Post)"        android:onClick="loginPost"        />    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="登录(AsyncHttpClient)"        android:onClick="loginAsyncHttpClient"        /></LinearLayout>

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);    }      //第一种：get    public void loginGet(View view){       String uname=et_main_uname.getText().toString();       String upass=et_main_upass.getText().toString();       String path="http://193.168.2.141:7788/G160628_Server/login.do";      new MyGetTask().execute(uname,upass,path);    }    class MyGetTask 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+"?uname="+uname+"&upass="+upass);                HttpURLConnection connection= (HttpURLConnection) url.openConnection();                connection.setRequestMethod("GET");                connection.setConnectTimeout(5000);                if(connection.getResponseCode()==200){                    InputStream is=connection.getInputStream();                    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) {            super.onPostExecute(o);            String s= (String) o;            Toast.makeText(MainActivity.this, s, Toast.LENGTH_SHORT).show();        }    } //第二种：post    public void loginPost(View view){       String uname=et_main_uname.getText().toString();       String upass=et_main_upass.getText().toString();       String path="http://193.168.2.141:7788/G160628_Server/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 conn= (HttpURLConnection) url.openConnection();                conn.setRequestMethod("POST");                conn.setConnectTimeout(5000);                //admin 123                //uname=admin&upass=123456                String s="uname="+uname+"&upass="+upass;                 //添加请求头                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                OutputStream os=conn.getOutputStream();                os.write(s.getBytes());                if(conn.getResponseCode()==200){                    InputStream is=conn.getInputStream();                    BufferedReader br=new BufferedReader(new InputStreamReader(is));                    String str=br.readLine();                    return str;                }            } catch (MalformedURLException e) {                e.printStackTrace();            } catch (IOException e) {                e.printStackTrace();            }            return null;        }        @Override        protected void onPostExecute(Object o) {            super.onPostExecute(o);            String s= (String) o;            Toast.makeText(MainActivity.this,s, Toast.LENGTH_SHORT).show();        }    }       //第三种：AsycnClient（需要导jar包：android-async-http-1.4.4.jar，并且进行网络配置）    public void loginAsyncHttpClient(View view){        String uname=et_main_uname.getText().toString();        String upass=et_main_upass.getText().toString();        String path="http://193.168.2.141:7788/G160628_Server/login.do";        AsyncHttpClient ahc=new AsyncHttpClient();        RequestParams params=new RequestParams();        params.put("uname",uname);        params.put("upass",upass);        ahc.post(this,path,params,new TextHttpResponseHandler(){            @Override            public void onFailure(int statusCode, Header[] headers, String responseBody, Throwable error) {                super.onFailure(statusCode, headers, responseBody, error);            }            @Override            public void onSuccess(int statusCode, Header[] headers, String responseBody) {                super.onSuccess(statusCode, headers, responseBody);                Toast.makeText(MainActivity.this, responseBody, Toast.LENGTH_SHORT).show();            }        });    }}

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.zking.administrator.g160628_android32_commitdata"><!--网络配置-->    <uses-permission android:name="android.permission.INTERNET"></uses-permission>    <application android:allowBackup="true" android:icon="@mipmap/ic_launcher"        android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round"        android:supportsRtl="true" android:theme="@style/AppTheme">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>

服务器端：

<%@ page language="java" contentType="text/html; charset=UTf-8"    pageEncoding="UTf-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTf-8"><title>Insert title here</title></head><body><h1>登录页面</h1><form action="login.do" method="post">用户名：<input type="text" name="uname"/><br/>密码：<input type="password" name="upass"/><br/><input type="submit" value="登录"/><br/></form></body></html>

public class LoginServlet extends HttpServlet{@Overrideprotected 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;//判断if("admin".equals(uname) && "123".equals(upass)){result="success";}else{result="fail";}PrintWriter pw=resp.getWriter();pw.write(result);pw.close();}}