即时通讯基础
即時(shí)通訊系列閱讀
1. 即時(shí)通訊簡介
即時(shí)通訊（Instant Messaging）是目前Internet 上最為流行的通訊方式，各種各樣的即時(shí)通訊軟件也層出不窮；服務(wù)提供商也提供了越來越豐富的通訊服務(wù)功能。不容置疑，Internet 已經(jīng)成為真正的信息高速公路。從實(shí)際工程應(yīng)用角度出發(fā)，以計(jì)算機(jī)網(wǎng)絡(luò)原理為指導(dǎo)，結(jié)合當(dāng)前網(wǎng)絡(luò)中的一些常用技術(shù)，編程實(shí)現(xiàn)基于C/S 架構(gòu)的網(wǎng)絡(luò)聊天工具是切實(shí)可行的。
目前，中國市場上的企業(yè)級(jí)即時(shí)通信工具主要包括：信鴿、視高科技的視高可視協(xié)同辦公平臺(tái)、263EM、群英CC2010、通軟聯(lián)合的GoCom、騰訊公司的RTX、IBM 的Lotus Sametime、點(diǎn)擊科技的GKE、中國互聯(lián)網(wǎng)辦公室的imo、中國移動(dòng)的企業(yè)飛信、華夏易聯(lián)的e-Link、擎旗的UcStar 等。相對于個(gè)人即時(shí)通信工具而言，企業(yè)級(jí)即時(shí)通信工具更加強(qiáng)調(diào)安全性、實(shí)用性、穩(wěn)定性和擴(kuò)展性。
1.1 即時(shí)聊天的解決方案
- socket：套接字，連接需要ip和端口，分為tcp和udp兩種形式
- xmpp：xmpp + openfire + asmack
1.2 常見協(xié)議
1.3 常見的術(shù)語
- xmpp:基于xml的可拓展協(xié)議.
- jabber:xmpp的前身.
- openfire:支持xmpp的開源服務(wù)器
- smack.jar:對xmpp協(xié)議封裝.方便開發(fā)的jar包.
- spark.exe:基于xmpp的pc客戶端;
- asmack.jar:smack.jar的精簡版.專門針對android端開發(fā)
2. 基本概念和原理
2.1 常用的網(wǎng)絡(luò)通信協(xié)議
TCP/IP：Transmission Control Protocol/Internet Protocol 的簡寫，中譯名為傳輸控制協(xié)議/因特網(wǎng)互聯(lián)協(xié)議，又名網(wǎng)絡(luò)通訊協(xié)議，是Internet 最基本的協(xié)議、Internet 國際互聯(lián)網(wǎng)絡(luò)的基礎(chǔ)，由網(wǎng)絡(luò)層的IP 協(xié)議和傳輸層的TCP協(xié)議組成。TCP/IP 定義了電子設(shè)備如何連入因特網(wǎng)，以及數(shù)據(jù)如何在它們之間傳輸?shù)臉?biāo)準(zhǔn)。協(xié)議采用了4 層的層級(jí)結(jié)構(gòu)，每一層都呼叫它的下一層所提供的協(xié)議來完成自己的需求。通俗而言：TCP 負(fù)責(zé)發(fā)現(xiàn)傳輸?shù)膯栴}，一有問題就發(fā)出信號(hào)，要求重新傳輸，直到所有數(shù)據(jù)安全正確地傳輸?shù)侥康牡亍６鳬P 是給因特網(wǎng)的每一臺(tái)聯(lián)網(wǎng)設(shè)備規(guī)定一個(gè)地址。
UDP：UDP 協(xié)議全稱是用戶數(shù)據(jù)報(bào)協(xié)議，在網(wǎng)絡(luò)中它與TCP 協(xié)議一樣用于處理數(shù)據(jù)包，是一種無連接的協(xié)議。在OSI 模型中，在第四層——傳輸層，處于IP 協(xié)議的上一層。UDP 有不提供數(shù)據(jù)包分組、組裝和不能對數(shù)據(jù)包進(jìn)行排序的缺點(diǎn)，也就是說，當(dāng)報(bào)文發(fā)送之后，是無法得知其是否安全完整到達(dá)的。UDP 用來支持那些需要在計(jì)算機(jī)之間傳輸數(shù)據(jù)的網(wǎng)絡(luò)應(yīng)用。包括網(wǎng)絡(luò)視頻會(huì)議系統(tǒng)在內(nèi)的眾多的客戶/服務(wù)器模式的網(wǎng)絡(luò)應(yīng)用都需要使用UDP協(xié)議。UDP 協(xié)議從問世至今已經(jīng)被使用了很多年，雖然其最初的光彩已經(jīng)被一些類似協(xié)議所掩蓋，但是即使是在今天UDP 仍然不失為一項(xiàng)非常實(shí)用和可行的網(wǎng)絡(luò)傳輸層協(xié)議。
TCP/IP 協(xié)議棧主要分為四層:應(yīng)用層、傳輸層、網(wǎng)絡(luò)層、數(shù)據(jù)鏈路層，每層都有相應(yīng)的協(xié)議，如下圖：
所謂的協(xié)議就是雙方進(jìn)行數(shù)據(jù)傳輸?shù)囊环N格式。
2.2 TCP、UDP 特點(diǎn)對比
TCP 協(xié)議是面向連接、保證高可靠性(數(shù)據(jù)無丟失、數(shù)據(jù)無失序、數(shù)據(jù)無錯(cuò)誤、數(shù)據(jù)無重復(fù)到達(dá))傳輸層協(xié)議。UDP 協(xié)議也是傳輸層協(xié)議，它是無連接，不保證可靠的傳輸層協(xié)議。
2.3 TCP 三次握手過程
1、請求端(通常稱為客戶)發(fā)送一個(gè)SYN 段指明客戶打算連接的服務(wù)器的端口，以及初始序號(hào)(ISN)
2、服務(wù)器發(fā)回包含服務(wù)器的初始序號(hào)的SYN 報(bào)文段(報(bào)文段2)作為應(yīng)答。同時(shí)，將確認(rèn)序號(hào)設(shè)置為客戶的ISN加1 以對客戶的SYN 報(bào)文段進(jìn)行確認(rèn)。
| 面向連接 | 面向非連接 |
| 可靠的連接 | 不可靠的連接 |
| 速度慢 | 速度快 |
| 大文件、重要的數(shù)據(jù)等 | 適合小數(shù)據(jù)、不重要 |
3、客戶必須將確認(rèn)序號(hào)設(shè)置為服務(wù)器的ISN 加1 以對服務(wù)器的SYN 報(bào)文段進(jìn)行確認(rèn)(報(bào)文段3)這三個(gè)報(bào)文段完成連接的建立。這個(gè)過程也稱為三次握手(three-way handshake)。
上面的過程如下圖所示：
2.4 即時(shí)通訊形式
直接通訊
兩個(gè)不同客戶端之間不經(jīng)過服務(wù)器，直接通過網(wǎng)絡(luò)進(jìn)行數(shù)據(jù)的交互。常用的p2p 技術(shù)就是直接通訊的形式。
在線代理通訊
一個(gè)客戶端發(fā)送的消息先發(fā)送到服務(wù)器，服務(wù)器接收到消息后再發(fā)送給指定的另外一個(gè)客戶端。QQ 的消息
尤其是離線消息就是同在線代理的方式實(shí)現(xiàn)的。
離線代理通訊
一個(gè)客戶端發(fā)送消息給服務(wù)器，服務(wù)器存儲(chǔ)在數(shù)據(jù)庫中個(gè)，當(dāng)另外一個(gè)客戶端上線后在發(fā)送過去。
離線擴(kuò)展通訊
一個(gè)客戶端發(fā)送消息給服務(wù)器，服務(wù)器通過郵件、短信等其他形式將消息發(fā)送給接收者。
3. ServerSocket 和Socket
3.1 使用Java 完成簡單的Socket 通信
在Java 中Socket 可以理解為客戶端或者服務(wù)器端的一個(gè)特殊的對象，這個(gè)對象有兩個(gè)關(guān)鍵的方法，一個(gè)是getInputStream 方法，另一個(gè)是getOutputStream 方法。getInputStream 方法可以得到一個(gè)輸入流，客戶端的Socket對象上的getInputStream 方法得到的輸入流其實(shí)就是從服務(wù)器端發(fā)回的數(shù)據(jù)流。GetOutputStream 方法得到一個(gè)輸出流，客戶端Socket 對象上的getOutputStream 方法返回的輸出流就是將要發(fā)送到服務(wù)器端的數(shù)據(jù)流，（其實(shí)是一個(gè)緩沖區(qū)，暫時(shí)存儲(chǔ)將要發(fā)送過去的數(shù)據(jù)）。
下面就讓我們寫一個(gè)簡單的Demo 來演示Socket 是如何使用的。
建立服務(wù)器類
服務(wù)類使用到的核心類的是ServerSocket。這里我們只需要建立一個(gè)Java Project 即可。
public class IMServer {private static ServerSocket serverSocket;private static BufferedReader reader;public static void main(String[] args) {try {serverSocket = new ServerSocket(7788);/*** 等待接收客戶端連接進(jìn)來，該方法是線程阻塞的*/Socket accept = serverSocket.accept();/*** 獲取輸入流，用于接收客戶端發(fā)來的數(shù)據(jù)*/InputStream inputStream = accept.getInputStream();/*** 將字節(jié)輸入流轉(zhuǎn)化為字符輸出流*/reader = new BufferedReader(new InputStreamReader(inputStream));/*** 打印數(shù)據(jù)*/String tmp = null;while ((tmp = reader.readLine()) != null) {System.out.println(tmp);}} catch (Exception e) {e.printStackTrace();} finally {try {if (serverSocket != null) {serverSocket.close();}} catch (IOException e) {e.printStackTrace();}if (reader != null) {try {reader.close();} catch (IOException e) {e.printStackTrace();}}}}}建立客戶端類
public class IMClient {private static Socket socket;private static BufferedWriter writer;/*** @param args*/public static void main(String[] args) {try {socket = new Socket("127.0.0.1", 7788);/*** 獲取輸出流*/OutputStream outputStream = socket.getOutputStream();writer = new BufferedWriter(new OutputStreamWriter(outputStream));writer.write("hello wo shi wzy!" + new Date().getTime());writer.close();} catch (IOException e) {e.printStackTrace();} finally {if (socket != null) {try {socket.close();} catch (IOException e) {e.printStackTrace();}}if (writer != null) {try {writer.close();} catch (IOException e) {e.printStackTrace();}}}}}在上面的代碼中我們僅僅實(shí)現(xiàn)了一個(gè)最簡單的服務(wù)器和客戶端，服務(wù)器啟動(dòng)起來后只能接受到一次消息，然后就關(guān)閉了。如果想讓服務(wù)器一直運(yùn)行，應(yīng)該通過死循環(huán)來處理不同的發(fā)送進(jìn)來的消息。
Socket調(diào)試工具
TCP/UDP Socket調(diào)試工具提供了TCP Server，TCP Client，UDP Server，UDP Client，UDP Group 五種Socket調(diào)試方案
TCP
手機(jī)作為Client，PC作為Server
public class MyClientActivity extends Activity {private EditText mEditText = null;private Button connectButton = null;private Button sendButton = null;private TextView mTextView = null;private Socket clientSocket = null;private OutputStream outStream = null;private Handler mHandler = null;private ReceiveThread mReceiveThread = null;private boolean stop = true;/** Called when the activity is first created. */@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);mEditText = (EditText) this.findViewById(R.id.edittext);mTextView = (TextView) this.findViewById(R.id.retextview);connectButton = (Button) this.findViewById(R.id.connectbutton);sendButton = (Button) this.findViewById(R.id.sendbutton);sendButton.setEnabled(false);// 連接按鈕監(jiān)聽connectButton.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubtry {// 實(shí)例化對象并連接到服務(wù)器clientSocket = new Socket("172.27.35.1", 60000);} catch (UnknownHostException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}displayToast("連接成功！");// 連接按鈕使能connectButton.setEnabled(false);// 發(fā)送按鈕使能sendButton.setEnabled(true);mReceiveThread = new ReceiveThread(clientSocket);stop = false;// 開啟線程mReceiveThread.start();}});// 發(fā)送數(shù)據(jù)按鈕監(jiān)聽sendButton.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubbyte[] msgBuffer = null;// 獲得EditTex的內(nèi)容String text = mEditText.getText().toString();try {// 字符編碼轉(zhuǎn)換msgBuffer = text.getBytes("GB2312");} catch (UnsupportedEncodingException e1) {// TODO Auto-generated catch blocke1.printStackTrace();}try {// 獲得Socket的輸出流outStream = clientSocket.getOutputStream();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {// 發(fā)送數(shù)據(jù)outStream.write(msgBuffer);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}// 清空內(nèi)容mEditText.setText("");displayToast("發(fā)送成功！");}});// 消息處理mHandler = new Handler() {@Overridepublic void handleMessage(Message msg) {// 顯示接收到的內(nèi)容mTextView.setText((msg.obj).toString());}};}// 顯示Toast函數(shù)private void displayToast(String s) {Toast.makeText(this, s, Toast.LENGTH_SHORT).show();}private class ReceiveThread extends Thread {private InputStream inStream = null;private byte[] buf;private String str = null;ReceiveThread(Socket s) {try {// 獲得輸入流this.inStream = s.getInputStream();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}@Overridepublic void run() {while (!stop) {this.buf = new byte[512];try {// 讀取輸入數(shù)據(jù)（阻塞）this.inStream.read(this.buf);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}// 字符編碼轉(zhuǎn)換try {this.str = new String(this.buf, "GB2312").trim();} catch (UnsupportedEncodingException e) {// TODO Auto-generated catch blocke.printStackTrace();}Message msg = new Message();msg.obj = this.str;// 發(fā)送消息mHandler.sendMessage(msg);}}}@Overridepublic void onDestroy() {super.onDestroy();if (mReceiveThread != null) {stop = true;mReceiveThread.interrupt();}}}手機(jī)作為Server，PC作為Client
public class MyServerActivity extends Activity {private TextView ipTextView = null;private EditText mEditText = null;private Button sendButton = null;private TextView mTextView = null;private OutputStream outStream = null;private Socket clientSocket = null;private ServerSocket mServerSocket = null;private Handler mHandler = null;private AcceptThread mAcceptThread = null;private ReceiveThread mReceiveThread = null;private boolean stop = true;/** Called when the activity is first created. */@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);ipTextView = (TextView) this.findViewById(R.id.iptextview);mEditText = (EditText) this.findViewById(R.id.sedittext);sendButton = (Button) this.findViewById(R.id.sendbutton);sendButton.setEnabled(false);mTextView = (TextView) this.findViewById(R.id.textview);// 發(fā)送數(shù)據(jù)按鈕監(jiān)聽sendButton.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubbyte[] msgBuffer = null;// 獲得EditTex的內(nèi)容String text = mEditText.getText().toString();try {// 字符編碼轉(zhuǎn)換msgBuffer = text.getBytes("GB2312");} catch (UnsupportedEncodingException e1) {// TODO Auto-generated catch blocke1.printStackTrace();}try {// 獲得Socket的輸出流outStream = clientSocket.getOutputStream();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {// 發(fā)送數(shù)據(jù)outStream.write(msgBuffer);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}// 清空內(nèi)容mEditText.setText("");displayToast("發(fā)送成功！");}});// 消息處理mHandler = new Handler() {@Overridepublic void handleMessage(Message msg) {switch (msg.what) {case 0: {// 顯示客戶端IPipTextView.setText((msg.obj).toString());// 使能發(fā)送按鈕sendButton.setEnabled(true);break;}case 1: {// 顯示接收到的數(shù)據(jù)mTextView.setText((msg.obj).toString());break;}}}};mAcceptThread = new AcceptThread();// 開啟監(jiān)聽線程mAcceptThread.start();}// 顯示Toast函數(shù)private void displayToast(String s) {Toast.makeText(this, s, Toast.LENGTH_SHORT).show();}private class AcceptThread extends Thread {@Overridepublic void run() {try {// 實(shí)例化ServerSocket對象并設(shè)置端口號(hào)為7100mServerSocket = new ServerSocket(60000);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {// 等待客戶端的連接（阻塞）clientSocket = mServerSocket.accept();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}mReceiveThread = new ReceiveThread(clientSocket);stop = false;// 開啟接收線程mReceiveThread.start();Message msg = new Message();msg.what = 0;// 獲取客戶端IPmsg.obj = clientSocket.getInetAddress().getHostAddress();// 發(fā)送消息mHandler.sendMessage(msg);}}private class ReceiveThread extends Thread {private InputStream mInputStream = null;private byte[] buf;private String str = null;ReceiveThread(Socket s) {try {// 獲得輸入流this.mInputStream = s.getInputStream();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}@Overridepublic void run() {while (!stop) {this.buf = new byte[512];// 讀取輸入的數(shù)據(jù)(阻塞讀)try {this.mInputStream.read(buf);} catch (IOException e1) {// TODO Auto-generated catch blocke1.printStackTrace();}// 字符編碼轉(zhuǎn)換try {this.str = new String(this.buf, "GB2312").trim();} catch (UnsupportedEncodingException e) {// TODO Auto-generated catch blocke.printStackTrace();}Message msg = new Message();msg.what = 1;msg.obj = this.str;// 發(fā)送消息mHandler.sendMessage(msg);}}}@Overridepublic void onDestroy() {super.onDestroy();if (mReceiveThread != null) {stop = true;mReceiveThread.interrupt();}}}UDP
public class MainActivity extends Activity {private static String TAG = "CallActivity";private Handler handler = new Handler() {public void handleMessage(android.os.Message msg) {// 播放聲音initBeepSound();playBeepSoundAndVibrate();Log.i(TAG, "reciever_msg");String result = (String) msg.obj;System.out.println(result);tv_result.setText(result);};};private String ip;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODOsuper.onCreate(savedInstanceState);setContentView(R.layout.activity_main);ip = IpUtil.getIp(this);Toast.makeText(this, ip, Toast.LENGTH_LONG).show();System.out.println("ip:" + ip);tv_result = (TextView) findViewById(R.id.tv_result);}/*** 發(fā)送者*/public void send(View v) {new Thread() {@Overridepublic void run() {try {//1. 創(chuàng)建一個(gè)DatagramSocket對象DatagramSocket socket = new DatagramSocket(5678);//2. 創(chuàng)建一個(gè) InetAddress ， 相當(dāng)于是地址,就是想要發(fā)送的ip地址InetAddress serverAddress = InetAddress.getByName("172.27.35.1");//3. 這是隨意發(fā)送一個(gè)數(shù)據(jù)String str = "來自android手機(jī)的問候";//4. 轉(zhuǎn)為byte類型byte data[] = str.getBytes("GBK");//5. 創(chuàng)建一個(gè)DatagramPacket 對象，并指定要講這個(gè)數(shù)據(jù)包發(fā)送到網(wǎng)絡(luò)當(dāng)中的哪個(gè)地址，以及端口號(hào)DatagramPacket pack = new DatagramPacket(data, data.length, serverAddress, 5678);//6. 調(diào)用DatagramSocket對象的send方法 發(fā)送數(shù)據(jù)socket.send(pack);} catch (SocketException e) {Log.i(TAG, "error");e.printStackTrace();} catch (UnknownHostException e) {Log.i(TAG, "error");e.printStackTrace();} catch (IOException e) {Log.i(TAG, "error");e.printStackTrace();}}}.start();}/*** 接收者* @param v*/public void receive(View v) {new Thread() {@Overridepublic void run() {// 執(zhí)行完畢后給handler發(fā)送一個(gè)空消息try {// 1. 創(chuàng)建一個(gè)DatagramSocket對象，并指定監(jiān)聽的端口號(hào)/\DatagramSocket socket = new DatagramSocket(5678);// 2. 創(chuàng)建一個(gè)byte數(shù)組用于接收byte data[] = new byte[1024];// 3. 創(chuàng)建一個(gè)空的DatagramPackage對象DatagramPacket pack = new DatagramPacket(data, data.length);// 4. 使用receive方法接收發(fā)送方所發(fā)送的數(shù)據(jù),同時(shí)這也是一個(gè)阻塞的方法while (true) {Log.i(TAG, "reciever_1");socket.receive(pack);Log.i(TAG, "reciever_2");// 5. 得到發(fā)送過來的數(shù)據(jù)// String result = new String(pack.getData(), pack.getOffset(), pack.getLength(),"GBK");String result = new String(pack.getData(), pack.getOffset(), pack.getLength());Message msg = new Message();msg.obj = result;handler.sendMessage(msg);Log.i(TAG, "sendmsg_1");}} catch (UnknownHostException e) {// TODO Auto-generated catch blocke.printStackTrace();Log.i(TAG, "error");} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();Log.i(TAG, "error");}}}.start();}@Overrideprotected void onDestroy() {super.onDestroy();}// 播放聲音private static final float BEEP_VOLUME = 0.10f;private MediaPlayer mediaPlayer;private void initBeepSound() {if (mediaPlayer == null) {setVolumeControlStream(AudioManager.STREAM_MUSIC);mediaPlayer = new MediaPlayer();mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);mediaPlayer.setOnCompletionListener(beepListener);AssetFileDescriptor file = getResources().openRawResourceFd(R.raw.beep);try {mediaPlayer.setDataSource(file.getFileDescriptor(), file.getStartOffset(), file.getLength());file.close();mediaPlayer.setVolume(BEEP_VOLUME, BEEP_VOLUME);mediaPlayer.prepare();} catch (IOException e) {mediaPlayer = null;}}}private void playBeepSoundAndVibrate() {if (mediaPlayer != null) {mediaPlayer.start();}// 震動(dòng)Vibrator mVibrator = (Vibrator) getApplication().getSystemService(Service.VIBRATOR_SERVICE);mVibrator.vibrate(2000);long[] pattern = { 0, 100, 200, 100, 200 };mVibrator.vibrate(pattern, -1);}private final OnCompletionListener beepListener = new OnCompletionListener() {public void onCompletion(MediaPlayer mediaPlayer) {mediaPlayer.seekTo(0);}};// 退出提醒private long exitTime;private TextView tv_result;@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {if (event.getAction() == KeyEvent.ACTION_DOWN && event.getKeyCode() == KeyEvent.KEYCODE_BACK) {if ((System.currentTimeMillis() - exitTime) > 2000) {Toast.makeText(getApplicationContext(), "再按一次退出" + getResources().getString(R.string.app_name),Toast.LENGTH_SHORT).show();exitTime = System.currentTimeMillis();} else {finish();}return true;}return super.onKeyDown(keyCode, event);} }IpUtil.java
public class IpUtil {/*** 獲取手機(jī)ip* * @return*/public static String getLocalIpAddress() {try {for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {NetworkInterface intf = en.nextElement();for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {InetAddress inetAddress = enumIpAddr.nextElement();if (!inetAddress.isLoopbackAddress()) {String ip = inetAddress.getHostAddress().toString();System.out.println("getLocalIpAddressIP:"+ip);return ip;}}}} catch (SocketException ex) {Log.e("ifo", ex.toString());}return "";}public static String getIp(Activity activity) {WifiManager wifiManager = (WifiManager) activity.getSystemService(Context.WIFI_SERVICE);WifiInfo wifiInfo = wifiManager.getConnectionInfo();int ipAddress = wifiInfo.getIpAddress();// 格式化IP address，例如：格式化前：1828825280，格式化后：192.168.1.109String ip = String.format("%d.%d.%d.%d", (ipAddress & 0xff), (ipAddress >> 8 & 0xff), (ipAddress >> 16 & 0xff), (ipAddress >> 24 & 0xff));System.out.println("getIpIP:"+ip);return ip;}}總結(jié)
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