안드로이드 자바 소켓서버 통신

●소켓

- 일상 용어에서는 전구를 끼울 수 있는 도구를 말한다. 자바언어에서는 네트워크를 제어하는 클래스를 의미한다.

자바에서는 개발자가 네트워크 전문지식이 없어도 프로그래밍적으로 제어가 가능하도록 추상화시켜 제공해준다.

●예제

서버

- ChatServer.java

package chat; import java.io.IOException; import java.net.InetAddress; import java.net.ServerSocket; import java.net.Socket; import java.util.Vector; public class ChatServer { //서버소켓 - 클라이언트의 접속을 받아들이는 클래스 int port=7777; ServerSocket server; Vector<ServerThread> connectList; public ChatServer() { connectList = new Vector<ServerThread>(); try { //서버객체 생성 server = new ServerSocket(port); while(true){ //접속자가 접속하는지 확인 //접속자가 있을때까지 대기,지연상태에 있다. Socket client = server.accept(); InetAddress inet = client.getInetAddress(); String ip = inet.getHostAddress(); System.out.println(ip+"-접속자 발견"); //대화용 쓰레드 생성 및 소켓 ServerThread serverThread = new ServerThread(connectList, client); System.out.println("start"); serverThread.start(); connectList.add(serverThread); System.out.println("현재 접속자수:"+connectList.size()); } /* //클라이언트의 메세지를 받아들여보자(입력) InputStream is = client.getInputStream(); //한글이 지원되지 않으므로 2바이트씩 처리하는 스트림으로 업그레이드 InputStreamReader reader;//문자기반스트림(2바이트씩 처리) reader = new InputStreamReader(is); //문자단위로 데이터를 처리하면 효율상 떨어지므로 //버퍼스트림으로 업그레이드 //버퍼처리된 문자기반 스트림 BufferedReader buffer = new BufferedReader(reader); //클라이언트가 보낸 메시지를 출력해보자(출력) OutputStream os = client.getOutputStream(); //문자기반 출력스트림 OutputStreamWriter writer = new OutputStreamWriter(os); //버퍼처리된 문자기반 출력 스트림 BufferedWriter bufferWriter = new BufferedWriter(writer); //int data; String data; while(true){ //클라이언트에서 메시지를 받는다. //data = is.read(); //data = reader.read(); data = buffer.readLine(); //System.out.print((char)data); System.out.println(data); //클라이언트에게 메시지를 보낸다. //os.write((char)data); //os.write(data); bufferWriter.write(data+"\n"); //출력스트림안의 데이터를 비우는것이다. //혹시라도 남아있을수 있는 데이터를 전부 내보냄 //os.flush(); bufferWriter.flush(); }*/ } catch (IOException e) { e.printStackTrace(); } } public static void main(String[] args) { new ChatServer(); //server = new ServerSocket(port); } }

- ServerThread.java

package chat; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.net.Socket; import java.util.Vector; public class ServerThread extends Thread{ Socket client; BufferedReader buffer; BufferedWriter bufferWriter; Vector<ServerThread> connectList; public ServerThread(Vector<ServerThread> connectList, Socket socket) { this.connectList = connectList; this.client = socket; try { buffer = new BufferedReader(new InputStreamReader((client.getInputStream()))); bufferWriter = new BufferedWriter(new OutputStreamWriter((client.getOutputStream()))); } catch (IOException e) { e.printStackTrace(); } } public void run() { while(true){ String msg = listen(); send(msg); } } //메시지 청취 public String listen(){ String msg=""; try { msg= buffer.readLine(); System.out.println("msg:"+msg); } catch (IOException e) { e.printStackTrace(); } return msg; } //메시지 전송 public void send(String msg){ try { for(int i=0;i<connectList.size();i++){ ServerThread st = connectList.get(i); st.bufferWriter.write(msg+"\n"); st.bufferWriter.flush(); } } catch (IOException e) { e.printStackTrace(); } } }

자바 클라이언트

- ChatClient.java

package chat; import java.awt.BorderLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.net.Socket; import java.net.UnknownHostException; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JTextField; //윈도우창은 개발자가 명시하지 않으면 디폴트로 BorderLayout이 적용된다. public class ChatClient extends JFrame implements ActionListener,KeyListener{ JButton btn; JTextArea area; JScrollPane scoll; JTextField input; Socket client; //대화형 소켓 String ip = "192.168.100.95"; int port = 7777; BufferedReader bufferR; BufferedWriter bufferW; public ChatClient() { btn = new JButton("접속"); area = new JTextArea(); scoll = new JScrollPane(area); input = new  JTextField(); btn.addActionListener(this); input.addKeyListener(this); this.add(btn, BorderLayout.NORTH); this.add(scoll); this.add(input,BorderLayout.SOUTH); setSize(300,400); setVisible(true); } //채팅서버에 접속 public void connect(){ try { client = new Socket(ip, port); //연결된 소켓으로부터 대화를 나눌 스트림을 얻자 bufferR = new BufferedReader(new InputStreamReader(client.getInputStream())); bufferW = new BufferedWriter(new OutputStreamWriter(client.getOutputStream())); } catch (UnknownHostException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } //서버에 메시지 보내기 public void listen(){ String msg=""; try { msg = bufferR.readLine(); area.append(msg+"\n"); } catch (IOException e) { e.printStackTrace(); } } //서버에서 메시지 청취하기 public void send(){ String v = input.getText(); try { bufferW.write(v+"\n"); bufferW.flush(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void actionPerformed(ActionEvent e) { System.out.println("클릭"); connect(); } public static void main(String[] args) { new ChatClient(); } //키를 누르골 있을때 public void keyPressed(KeyEvent e) { } //키를 눌렀다 땠을때 public void keyReleased(KeyEvent e) { System.out.println("키:"+e.getKeyCode()); if(e.getKeyCode()==KeyEvent.VK_ENTER){ System.out.println("엔터"); send(); input.setText(""); listen(); } } //타이핑하면 public void keyTyped(KeyEvent e) { } }

안드로이드 클라이언트

- MainActivity.java

package com.example.chatclient; import java.io.IOException; import java.net.Socket; import java.net.UnknownHostException; import java.util.Vector; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; public class MainActivity extends Activity implements OnClickListener{ Button btn; TextView textView; EditText editText; Button btn_send; Socket client; String ip = "192.168.100.95"; int port = 7777; Thread thread; ClientThread clientThread; Handler handler; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btn = (Button)findViewById(R.id.btn); textView = (TextView)findViewById(R.id.textView); editText = (EditText)findViewById(R.id.editText); btn_send = (Button)findViewById(R.id.btn_send); handler = new Handler(){ public void handleMessage(Message msg) { super.handleMessage(msg); Bundle bundle = msg.getData(); textView.append(bundle.getString("msg")+"\n"); } }; btn.setOnClickListener(this); btn_send.setOnClickListener(this); } public void connect(){ thread = new Thread(){ public void run() { super.run(); try { client = new Socket(ip, port); clientThread = new ClientThread(client, handler); clientThread.start(); } catch (UnknownHostException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }; thread.start(); } @Override public void onClick(View v) { if(v.getId()==R.id.btn){ connect(); } if(v.getId()==R.id.btn_send){ clientThread.send(editText.getText().toString()); editText.setText(""); } } }

- ClientThread.java

package com.example.chatclient; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.net.Socket; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.widget.TextView; public class ClientThread extends Thread{ BufferedReader bufferR; BufferedWriter bufferW; Socket client; Handler handler; public ClientThread(Socket client, Handler handler) { this.handler = handler; try { this.client = client; //연결된 소켓으로부터 대화를 나눌 스트림을 얻음 bufferR = new BufferedReader(new InputStreamReader(client.getInputStream())); bufferW = new BufferedWriter(new OutputStreamWriter(client.getOutputStream())); } catch (IOException e) { e.printStackTrace(); } } //보내기 public void send(String data){ System.out.println("전송"); try { System.out.println("data:"+data); bufferW.write(data+"\n"); bufferW.flush(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } //받기 public String listen(){ String msg=null; try { while(true){ msg=bufferR.readLine(); Message m = new Message(); Bundle bundle = new Bundle(); bundle.putString("msg", msg); m.setData(bundle); handler.sendMessage(m); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return msg; } public void run() { super.run(); listen(); } }

- activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     android:id="@+id/LinearLayout1"     android:layout_width="match_parent"     android:layout_height="match_parent"     android:orientation="vertical"     tools:context="${relativePackage}.${activityClass}" >     <Button          android:id="@+id/btn"         android:layout_width="wrap_content"         android:layout_height="0dp"         android:text="접속"         android:layout_weight="1"         android:layout_gravity="center_horizontal"/>      <TextView     android:id="@+id/textView"    android:layout_width="match_parent"    android:layout_height="0dp"         android:layout_weight="10"/>                        <EditText          android:id="@+id/editText"         android:layout_width="match_parent"         android:layout_height="0dp"         android:background="#ffdd00"         android:layout_weight="1"/>          <Button          android:id="@+id/btn_send"         android:layout_width="match_parent"         android:layout_height="0dp"         android:text="전송"         android:layout_weight="1"         android:layout_gravity="center_horizontal"/>           </LinearLayout>