0912Android基础网络技术之Http协议访问网络

使用HTTP协议访问网络

　　它的工作原始，客户端向服务器发出一条HTTP请求，服务器收到请求后会返回一些数据给客户端，然后客户端对这些数据进行解析和处理。包含HttpUrlConnection和HttpClient

通过urlConnection读取网页中的数据

　　首先的首先还是要先添加权限

<uses-permission android:name="android.permission.INTERNET" />

　　设置一个按键触发事件,将访问网络写在线程里，因为访问网络是耗时操作，耗时操作不能直接写在主线程里面。

 public void onClick(View v) {        switch (v.getId()) {            case R.id.btn_read:                new Thread(new Runnable() {                    @Override                    public void run() {                        connectServerlet();                    }                }).start();                break; }

　　线程 connectServerlet(),将获得的信息通过Message传到Handler中，进而设置UI。

 private void connectServerlet() {        try {            URL url = new URL("http://192.168.0.44:8080/MyServiceTest/MyTestServlet");//            URL url = new URL("http://www.360.com");            URLConnection connection = url.openConnection();            InputStream is = connection.getInputStream();            BufferedReader reader = new BufferedReader(new InputStreamReader(is));            String line = reader.readLine();//            新建stringbuffer对象            mStringBuffer = new StringBuffer();            while (line != null) {                mStringBuffer.append(line);                Log.d("读取服务器的内容", " " + line);                line = reader.readLine();            }//            将数据传入handler            Message msg = handler.obtainMessage();            msg.what = SEND_MESSAGE;            msg.obj = mStringBuffer.toString().trim();// trim去掉空格            handler.sendMessage(msg);            reader.close();            is.close();        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }

　　Handler记得导这个包import android.os.Handler;

private Handler handler = new Handler() {        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            switch (msg.what) {                case SEND_MESSAGE:                    String content = (String) msg.obj;                    mTvMessage.setText(content);                    break;                default:                    break;            }        }    };

　　全部代码见主线程代码
　　达到的效果

HttpURLConnection

　　添加权限

<uses-permission android:name="android.permission.INTERNET" />

　　另外开一个活动，通过intent进行通信

 Intent intenthttpUrl=new Intent(getApplicationContext(),MyHttpURLConnection.class);                startActivity(intenthttpUrl);

　　在AndroidMainfest中注册(具体位置见下面主线程代码)

<activity android:name=".MyHttpURLConnection"></activity>

　　doget和dopost方法

package com.example.laowang.myinternet;import android.app.Activity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.ProtocolException;import java.net.URL;import java.net.URLConnection;public class MyHttpURLConnection extends Activity implements View.OnClickListener{    private Button mBtnHttpURlGet;    private Button mBtnHttpURlPost;    private StringBuffer mStringBuffer;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_httpurl);        mBtnHttpURlGet= (Button) findViewById(R.id.btn_httpurl_doget);        mBtnHttpURlPost= (Button) findViewById(R.id.btn_httpurl_dopost);        mBtnHttpURlGet.setOnClickListener(this);        mBtnHttpURlPost.setOnClickListener(this);    }    @Override    public void onClick(View v) {        switch (v.getId()){            case R.id.btn_httpurl_doget:                new Thread(new Runnable() {                    @Override                    public void run() {                        doGet();                    }                }).start();                break;            case R.id.btn_httpurl_dopost:                new Thread(new Runnable() {                    @Override                    public void run() {                        doPost();                    }                }).start();                break;            default:                break;        }    }    private void doPost() {        String urlString1="http://192.168.0.44:8080/MyServiceTest/MyTestServlet";        try {            URL url1= new URL(urlString1);            HttpURLConnection connection=(HttpURLConnection) url1.openConnection();//强制转型            //HttpURLConnection进行控制            //设置连接超时时间            connection.setConnectTimeout(30000);            //读取超时时间            connection.setReadTimeout(30000);            //设置编码格式            // 设置接受的数据类型            connection.setRequestProperty("Accept-Charset", "utf-8");            // 设置可以接受序例化的java对象            connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");            //客户端输出部分            //设置 URL 请求的方法            connection.setRequestMethod("POST");            //设置客户端可以给服务器提交数据，默认是false的,POST时必须改成true            connection.setDoOutput(true);            //设置可以读取服务器返回的内容，默认为true，不写也可以            connection.setDoInput(true);            //post方法不允许使用缓存            connection.setUseCaches(false);            String params="username=HttpURLConnectionDoPost&password=123456";            connection.getOutputStream().write(params.getBytes());//客户端输出数据            InputStream is = connection.getInputStream();            BufferedReader reader = new BufferedReader(new InputStreamReader(is));            String line = reader.readLine();//            新建stringbuffer对象            mStringBuffer = new StringBuffer();            while (line != null) {                mStringBuffer.append(line);                Log.d("读取服务器的内容", " " + line);                line = reader.readLine();            }        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (ProtocolException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }    private void doGet() {        try {            //基本设置，设置URL连接，设置HttpURLConnection            String urlString = "http://192.168.0.44:8080/MyServiceTest/MyTestServlet?username=HttpURLConnectionDoGet&password=123456";            URL url = new URL(urlString);//生成url            URLConnection connect = url.openConnection();//打开url连接            //强制造型成httpUrlConnection            HttpURLConnection httpConnection = (HttpURLConnection) connect;            //设置请求方法            httpConnection.setRequestMethod("GET");            //设置连接超时的时间            httpConnection.setConnectTimeout(3000);            //读取时间超时            httpConnection.setReadTimeout(3000);            //设置编码格式            // 设置接受的数据类型            httpConnection.setRequestProperty("Accept-Charset", "utf-8");            // 设置可以接受序例化的java对象            httpConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");            InputStream is = connect.getInputStream();            BufferedReader reader = new BufferedReader(new InputStreamReader(is));            String line = reader.readLine();//            新建stringbuffer对象            mStringBuffer = new StringBuffer();            while (line != null) {                mStringBuffer.append(line);                Log.d("读取服务器的内容", " " + line);                line = reader.readLine();            }        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (ProtocolException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }}

　　达到的效果
doget

dopost

HttpClient

　　添加权限

    <uses-permission android:name="android.permission.INTERNET" />

　　另外开一个活动，通过intent进行通信

Intent intent1 = new Intent(getApplicationContext(), MyHttpClientActivity.class);                startActivity(intent1);

　　在AndroidMainfest中注册(具体位置见下面主线程代码)

        <activity android:name=".MyHttpClientActivity"></activity>

　　doget和dopost方法

package com.example.laowang.myinternet;import android.app.Activity;import android.os.AsyncTask;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.TextView;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.StatusLine;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.HttpClient;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.HttpGet;import org.apache.http.client.methods.HttpPost;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.message.BasicNameValuePair;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.util.ArrayList;public class MyHttpClientActivity extends Activity implements View.OnClickListener{    private Button mBtnClientDoPost;    private Button mBtnClientDoGet;    private TextView mTvClientBack;    private String line;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_httpclient);        mBtnClientDoGet= (Button) findViewById(R.id.btn_client_doget);        mBtnClientDoPost= (Button) findViewById(R.id.btn_client_dopost);        mTvClientBack= (TextView) findViewById(R.id.tv_client_back);        mBtnClientDoPost.setOnClickListener(this);        mBtnClientDoGet.setOnClickListener(this);    }    @Override    public void onClick(View v) {        switch (v.getId()){            case R.id.btn_client_doget:                new MyAsyncTask().execute();                break;            case R.id.btn_client_dopost:                new Thread(new Runnable() {                    @Override                    public void run() {                        httpDoPost();                    }                }).start();                break;            default:                break;        }    }    private void httpDoPost() {        String urlString = "http://192.168.0.44:8080/MyServiceTest/MyTestServlet";        HttpClient client=new DefaultHttpClient();        //设置客户端输出信息        NameValuePair pair1=new BasicNameValuePair("username", "HttpClientPost");        NameValuePair pair2=new BasicNameValuePair("password", "123456");        ArrayList<NameValuePair> array=new ArrayList<>();        array.add(pair2);        array.add(pair1);        // post方法        // 设置post方法及环境        HttpPost post = new HttpPost(urlString);        try {            //设置传递的参数格式            post.setEntity(new UrlEncodedFormEntity(array, "UTF-8"));            post.setHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");            // 执行post方法法获得服务器返回的所有数据            HttpResponse response = client.execute(post);            // 接收处理服务器返回数据            // 获得服务器返回的表头            StatusLine statusLine = response.getStatusLine();            // 获得状态码            int code = statusLine.getStatusCode();            if (code == HttpURLConnection.HTTP_OK) {                // 获得数据实体                HttpEntity entity = response.getEntity();                // 获得数据的输入流并读入                InputStream is = entity.getContent();                BufferedReader br = new BufferedReader(new InputStreamReader(is));                String line = br.readLine();                while (line != null) {                    System.out.println(line);                    line = br.readLine();                }            }        } catch (ClientProtocolException e1) {            e1.printStackTrace();        } catch (IOException e1) {            e1.printStackTrace();        }    }    class MyAsyncTask extends AsyncTask<String ,Integer,String>{        @Override        protected void onPostExecute(String s) {            super.onPostExecute(s);        }        @Override        protected void onProgressUpdate(Integer... values) {            super.onProgressUpdate(values);        }        @Override        protected String doInBackground(String... params) {            HttpClient client=new DefaultHttpClient();            // 建立client            String urlString = "http://192.168.0.44:8080/MyServiceTest/MyTestServlet?username=HttpClientGet&password=123456";            // 设置get方法及环境            HttpGet get = new HttpGet(urlString);            get.setHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");            try {                // 执行get方法法获得服务器返回的所有数据                HttpResponse response = client.execute(get);                // 接收处理服务器返回数据                // 获得服务器返回的表头                StatusLine statusLine = response.getStatusLine();                // 获得状态码                int code = statusLine.getStatusCode();                if (code == HttpURLConnection.HTTP_OK) {                    // 获得数据实体                    HttpEntity entity = response.getEntity();                    // 获得数据的输入流并读入                    InputStream is = entity.getContent();                    BufferedReader br = new BufferedReader(new InputStreamReader(is));                    line = br.readLine();                    while (line != null) {                        line = br.readLine();                    }                }            } catch (ClientProtocolException e1) {                e1.printStackTrace();            } catch (IOException e1) {                e1.printStackTrace();            }            return "登录成功";        }    }}

　　达到的效果
doget

　　
dopost

主线程代码

　　这个主线程也用于后面的下载、XUtils、Volley中

package com.example.laowang.myinternet;import android.app.Activity;import android.content.Intent;import android.os.Handler;import android.os.Message;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.TextView;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.ProtocolException;import java.net.URL;import java.net.URLConnection;public class MainActivity extends Activity implements View.OnClickListener {    private Button mBtnRead;    private Button mBtnURLConnection;    private Button mBtnVolley;    private Button mBtnDownLoad;    private Button mBtnHttpClient;    private Button mBtnHttpUtils;    private TextView mTvMessage;    private StringBuffer mStringBuffer;    private static final int SEND_MESSAGE = 0x222;    private Handler handler = new Handler() {        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            switch (msg.what) {                case SEND_MESSAGE:                    String content = (String) msg.obj;                    mTvMessage.setText(content);                    break;                default:                    break;            }        }    };    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mBtnRead = (Button) findViewById(R.id.btn_read);        mBtnURLConnection = (Button) findViewById(R.id.btn_url_connection);        mBtnVolley = (Button) findViewById(R.id.btn_volley_get);        mBtnDownLoad = (Button) findViewById(R.id.btn_download);        mTvMessage = (TextView) findViewById(R.id.tv_message);        mBtnHttpClient = (Button) findViewById(R.id.btn_http_client);        mBtnHttpUtils = (Button) findViewById(R.id.btn_httputils_get);        mBtnRead.setOnClickListener(this);        mBtnURLConnection.setOnClickListener(this);        mBtnVolley.setOnClickListener(this);        mBtnDownLoad.setOnClickListener(this);        mBtnHttpClient.setOnClickListener(this);        mBtnHttpUtils.setOnClickListener(this);    }    @Override    public void onClick(View v) {        switch (v.getId()) {            case R.id.btn_read:                new Thread(new Runnable() {                    @Override                    public void run() {                        connectServerlet();                    }                }).start();                break;            case R.id.btn_url_connection:                Intent intenthttpUrl=new Intent(getApplicationContext(),MyHttpURLConnection.class);                startActivity(intenthttpUrl);                break;            case R.id.btn_download:                Intent intent = new Intent(getApplicationContext(), SecondActivity.class);                startActivity(intent);                break;            case R.id.btn_volley_get:                Intent intentVolley = new Intent(getApplicationContext(), MyVolleyActivity.class);                startActivity(intentVolley);                break;            case R.id.btn_http_client:                Intent intent1 = new Intent(getApplicationContext(), MyHttpClientActivity.class);                startActivity(intent1);                break;            case R.id.btn_httputils_get:                Intent intentUtils = new Intent(getApplicationContext(), MyXUtils.class);                startActivity(intentUtils);                break;            default:                break;        }    }    private void connectServerlet() {        try {            URL url = new URL("http://192.168.0.44:8080/MyServiceTest/MyTestServlet");//            URL url = new URL("http://www.360.com");            URLConnection connection = url.openConnection();            InputStream is = connection.getInputStream();            BufferedReader reader = new BufferedReader(new InputStreamReader(is));            String line = reader.readLine();//            新建stringbuffer对象            mStringBuffer = new StringBuffer();            while (line != null) {                mStringBuffer.append(line);                Log.d("读取服务器的内容", " " + line);                line = reader.readLine();            }//            将数据传入handler            Message msg = handler.obtainMessage();            msg.what = SEND_MESSAGE;            msg.obj = mStringBuffer.toString().trim();// trim去掉空格            handler.sendMessage(msg);            reader.close();            is.close();        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }}

　　AndroidMainfest

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.laowang.myinternet">    <uses-permission android:name="android.permission.INTERNET" />    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme">        <activity            android:name=".MainActivity"            android:label="@string/app_name">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>        <activity android:name=".SecondActivity"></activity>        <activity android:name=".MyHttpClientActivity"></activity>        <activity android:name=".MyVolleyActivity"></activity>        <activity android:name=".MyXUtils"></activity>        <activity android:name=".MyHttpURLConnection"></activity>    </application></manifest>