[Android]正确地访问网络资源----Proxy的使用
天朝有很多独特的东西，今天要涉及到的是CMWAP与CMNET。
现在仍有许多Android手机用的是CMWAP连接网络的，如果只是简单滴使用URL.openConnection()开启一个HttpURLConnection，则会发现有一个UnknownHostException被抛出。唉...身为悲剧的程序员，就要开始解决这种bug了。
Sodino还发现一个现象，为什么自己的程序会崩掉，而Google浏览器就不会呢？与国产软件不同，国产软件身处天朝的软硬件环境下成长，可能会将代理IP（10.0.0.172）写进程序中，Sodino也确实反编译了几个程序后发现他们也是这样做来保持CMWAP下的正常联接。但是，Google浏览器可不是国人写的，那帮老外可不考虑天朝还有个CMWAP。那他们是如何保证网络的正常联接呢？一番鼓捣下，有了以下代码，可以在WIFI/CMWAP/CMNET/CTNET下正常访问网络，附带如何使用ping使用。
先上效果图：
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package lab.sodino.network;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.UnknownHostException;
import android.app.Activity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class NetworkAct extends Activity {
public static final int CLEAR_TEXT = 0;
public static final int APPEND_TEXT = 1;
private TextView txtInfo;
private Button btnPing;
private Button btnConnect;
private Button btnClear;
private BtnListener btnListener;
private Handler handler = new Handler() {
public void handleMessage(Message msg) {
switch (msg.what) {
case APPEND_TEXT:
String content = msg.obj.toString();
txtInfo.setText("\n" + content);
break;
case CLEAR_TEXT:
txtInfo.setText("");
break;
}
}
};
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btnListener = new BtnListener();
txtInfo = (TextView) findViewById(R.id.txtInfo);
btnPing = (Button) findViewById(R.id.btnPing);
btnPing.setOnClickListener(btnListener);
btnConnect = (Button) findViewById(R.id.btnConnect);
btnConnect.setOnClickListener(btnListener);
btnClear = (Button) findViewById(R.id.btnClear);
btnClear.setOnClickListener(btnListener);
}
/**
* @param param
* 指定的域名如(www.google.com)或IP地址。
*/
private void doPing(final String param) {
new Thread() {
public void run() {
String line = "";
InputStream is = null;
try {
line = "\nping -c 1 " + param;
// -c 1:表示ping的次数为1次。
Process p = Runtime.getRuntime().exec("ping -c 1 www.google.com");
// 等待该命令执行完毕。
int status = p.waitFor();
if (status == 0) {
// 正常退出
line += "Pass";
} else {
// 异常退出
line += "Fail: Host unreachable";
}
is = p.getInputStream();
byte[] data = new byte[is.available()];
is.read(data);
line += "\n" + new String(data);
} catch (UnknownHostException e) {
line += "Fail: Unknown Host";
} catch (IOException e) {
line += "Fail: IOException";
} catch (InterruptedException e) {
line += "Fail: InterruptedException";
}
Message msg = new Message();
msg.what = APPEND_TEXT;
msg.obj = line;
handler.sendMessage(msg);
}
}.start();
}
private void go2Network() {
new Thread() {
public void run() {
String line = "";
URL url = null;
HttpURLConnection httpConn = null;
InputStream is = null;
try {
url = new URL("http://www.sodino.com/index.html");
// Log.d("ANDROID_LAB", "Protocol=" + new
// URL("https://www.sodino.com").getProtocol());
// 需要android.permission.ACCESS_NETWORK_STATE
NetworkInfo networkInfo = ((ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE))
.getActiveNetworkInfo();
// 如果是使用的运营商网络
if (networkInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
// 获取默认代理主机ip
String host = android.net.Proxy.getDefaultHost();
// 获取端口
int port = android.net.Proxy.getDefaultPort();
if (host != null && port != -1) {
line += "\nhost[" + host + "] port[" + port + "]";
// 封装代理連接主机IP与端口号。
InetSocketAddress inetAddress = new InetSocketAddress(host, port);
// 根据URL链接获取代理类型，本链接适用于TYPE.HTTP
java.net.Proxy.Type proxyType = java.net.Proxy.Type.valueOf(url
.getProtocol().toUpperCase());
java.net.Proxy javaProxy = new java.net.Proxy(proxyType, inetAddress);
httpConn = (HttpURLConnection) url.openConnection(javaProxy);
} else {
httpConn = (HttpURLConnection) url.openConnection();
}
} else {
httpConn = (HttpURLConnection) url.openConnection();
}
httpConn.connect();
int length = httpConn.getContentLength();
byte[] data = new byte[length];
String encoding = httpConn.getContentEncoding();
line += "\nlength=" + length + " encoding=" + encoding;
is = httpConn.getInputStream();
is.read(data);
String content = null;
if (encoding != null) {
content = new String(data, encoding);
} else {
content = new String(data);
}
line += "\nContent[\n" + content + "\n]";
Message msg = new Message();
msg.what = APPEND_TEXT;
msg.obj = line;
handler.sendMessage(msg);
} catch (IOException ie) {
ie.printStackTrace();
} finally {
try {
if (is != null) {
is.close();
}
if (httpConn != null) {
httpConn.disconnect();
}
} catch (IOException ie) {
ie.printStackTrace();
}
}
}
}.start();
}
class BtnListener implements Button.OnClickListener {
public void onClick(View view) {
if (view == btnPing) {
// doPing("www.google.com");
doPing("10.0.0.172");
} else if (view == btnConnect) {
go2Network();
} else if (view == btnClear) {
Message msg = new Message();
msg.what = CLEAR_TEXT;
handler.sendMessage(msg);
}
}
}
}
package lab.sodino.network;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.UnknownHostException;
import android.app.Activity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class NetworkAct extends Activity {
public static final int CLEAR_TEXT = 0;
public static final int APPEND_TEXT = 1;
private TextView txtInfo;
private Button btnPing;
private Button btnConnect;
private Button btnClear;
private BtnListener btnListener;
private Handler handler = new Handler() {
public void handleMessage(Message msg) {
switch (msg.what) {
case APPEND_TEXT:
String content = msg.obj.toString();
txtInfo.setText("\n" + content);
break;
case CLEAR_TEXT:
txtInfo.setText("");
break;
}
}
};
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btnListener = new BtnListener();
txtInfo = (TextView) findViewById(R.id.txtInfo);
btnPing = (Button) findViewById(R.id.btnPing);
btnPing.setOnClickListener(btnListener);
btnConnect = (Button) findViewById(R.id.btnConnect);
btnConnect.setOnClickListener(btnListener);
btnClear = (Button) findViewById(R.id.btnClear);
btnClear.setOnClickListener(btnListener);
}
/**
* @param param
* 指定的域名如(www.google.com)或IP地址。
*/
private void doPing(final String param) {
new Thread() {
public void run() {
String line = "";
InputStream is = null;
try {
line = "\nping -c 1 " + param;
// -c 1:表示ping的次数为1次。
Process p = Runtime.getRuntime().exec("ping -c 1 www.google.com");
// 等待该命令执行完毕。
int status = p.waitFor();
if (status == 0) {
// 正常退出
line += "Pass";
} else {
// 异常退出
line += "Fail: Host unreachable";
}
is = p.getInputStream();
byte[] data = new byte[is.available()];
is.read(data);
line += "\n" + new String(data);
} catch (UnknownHostException e) {
line += "Fail: Unknown Host";
} catch (IOException e) {
line += "Fail: IOException";
} catch (InterruptedException e) {
line += "Fail: InterruptedException";
}
Message msg = new Message();
msg.what = APPEND_TEXT;
msg.obj = line;
handler.sendMessage(msg);
}
}.start();
}
private void go2Network() {
new Thread() {
public void run() {
String line = "";
URL url = null;
HttpURLConnection httpConn = null;
InputStream is = null;
try {
url = new URL("http://www.sodino.com/index.html");
// Log.d("ANDROID_LAB", "Protocol=" + new
// URL("https://www.sodino.com").getProtocol());
// 需要android.permission.ACCESS_NETWORK_STATE
NetworkInfo networkInfo = ((ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE))
.getActiveNetworkInfo();
// 如果是使用的运营商网络
if (networkInfo.getType() == ConnectivityManager.TYPE_MOBILE) {
// 获取默认代理主机ip
String host = android.net.Proxy.getDefaultHost();
// 获取端口
int port = android.net.Proxy.getDefaultPort();
if (host != null && port != -1) {
line += "\nhost[" + host + "] port[" + port + "]";
// 封装代理連接主机IP与端口号。
InetSocketAddress inetAddress = new InetSocketAddress(host, port);
// 根据URL链接获取代理类型，本链接适用于TYPE.HTTP
java.net.Proxy.Type proxyType = java.net.Proxy.Type.valueOf(url
.getProtocol().toUpperCase());
java.net.Proxy javaProxy = new java.net.Proxy(proxyType, inetAddress);
httpConn = (HttpURLConnection) url.openConnection(javaProxy);
} else {
httpConn = (HttpURLConnection) url.openConnection();
}
} else {
httpConn = (HttpURLConnection) url.openConnection();
}
httpConn.connect();
int length = httpConn.getContentLength();
byte[] data = new byte[length];
String encoding = httpConn.getContentEncoding();
line += "\nlength=" + length + " encoding=" + encoding;
is = httpConn.getInputStream();
is.read(data);
String content = null;
if (encoding != null) {
content = new String(data, encoding);
} else {
content = new String(data);
}
line += "\nContent[\n" + content + "\n]";
Message msg = new Message();
msg.what = APPEND_TEXT;
msg.obj = line;
handler.sendMessage(msg);
} catch (IOException ie) {
ie.printStackTrace();
} finally {
try {
if (is != null) {
is.close();
}
if (httpConn != null) {
httpConn.disconnect();
}
} catch (IOException ie) {
ie.printStackTrace();
}
}
}
}.start();
}
class BtnListener implements Button.OnClickListener {
public void onClick(View view) {
if (view == btnPing) {
// doPing("www.google.com");
doPing("10.0.0.172");
} else if (view == btnConnect) {
go2Network();
} else if (view == btnClear) {
Message msg = new Message();
msg.what = CLEAR_TEXT;
handler.sendMessage(msg);
}
}
}
}
如此，悲剧的程序员解决了不同网络状态下如何保证正常链接的问题。
最后补充下：Android手机在CMWAP上要能够正常上网，除了设置一大堆代理数据外，还需进入拨号器下按"*#*#4636#*#*"→Phone Information下拉到最后后有个“Toggle DNS Check”，将其设置为allow
转载自：http://blog.csdn.net/sodino/archive/2011/04/05/6302313.aspx