Java 네트워크 - 3

6. 클라이언트 소켓

데이터는 “데이터그램”이라고 불리우는 한정된 크기의 패킷 형태로 존재한다. 데이터그램은 “헤더”와 “페이로드”로 구성되어 있다. 헤더에는 이 패킷이 어디로 가고 있는지를 나타내는 목적지 주소와 포트 번호, 어디에서 왔는지를 나타내는 출발지 주소와 포트 번호, 그리고 패킷이 정확히 전달 되도록 하기 위해서 필요한 여러 정보들이 들어있다.

• public Socket(String host, int port) throws UnknownHostException, IOException

• public Socket(InetAddress address, int port) throws IOException

• public InetAddress getInetAddress() : 소켓의 접속처의 주소를 돌려준다.

• public InetAddress getLocalAddress()

• public int getPort()

• public int getLocalPort() : 이 소켓에 바인딩된 로컬 포트를 돌려준다.

• public InputStream getInputStream() throw IOException : 소켓으로부터 들어오는 원시 데이터를 반환

• public OutputStream getOutputStream() throw IOException : 소켓으로 데이터를 보내기 위해 사용되는 원시 OutputSteam을 반환한다.

• public synchronized void close() throws IOException : 소켓을 닫습니다.

① package network.net.whois; ② import java.awt.Frame; ③ import java.awt.event.WindowAdapter; ④ import java.awt.event.WindowEvent; ⑤ import javax.swing.UIManager; ⑥ import java.awt.Dimension; ⑦ import java.awt.Toolkit; ⑧ ⑨ public class whoIsMain { ⑩ public whoIsMain() { ⑪ Frame frame = new whoIsFrame(); ⑫ Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); ⑬ Dimension frameSize = frame.getSize(); ⑭ if (frameSize.height > screenSize.height) { ⑮ frameSize.height = screenSize.height; 16 } 17 if (frameSize.width > screenSize.width) { 18 frameSize.width = screenSize.width; 19 } 20 frame.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2); 21 frame.addWindowListener(new WindowAdapter() { 22 public void windowClosing(WindowEvent e) { 23 System.exit(0); 24 } 25 }); 26 frame.setVisible(true); 27 } 28 29 public static void main(String[] args) { 30 try { 31 UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); 32 } catch(Exception e) { 33 e.printStackTrace(); 34 } 35 new whoIsMain(); 36 } 37 } 38 39 package network.net.whois; 40 import javax.swing.JFrame; 41 import java.awt.Dimension; 42 import javax.swing.JLabel; 43 import java.awt.Rectangle; 44 import javax.swing.JTextField; 45 import javax.swing.JCheckBox; 46 import javax.swing.JScrollPane; 47 import javax.swing.JButton; 48 import javax.swing.JTextPane; 49 import java.awt.event.ActionListener; 50 import java.awt.event.ActionEvent; 51 import java.awt.event.KeyListener; 52 import java.awt.event.KeyEvent; 53 import java.awt.event.MouseListener; 54 import java.awt.event.MouseEvent; 55 import java.net.*; 56 import java.io.*; 57 58 public class whoIsFrame extends JFrame { 59 private JLabel jLabel1 = new JLabel(); 60 private JTextField name = new JTextField(); 61 private JScrollPane messageScrollPane = new JScrollPane(); 62 private JButton search = new JButton(); 63 private JTextPane messagePane = new JTextPane(); 64 65 public whoIsFrame() { 66 try { 67 jbInit(); 68 } catch(Exception e) { 69 e.printStackTrace(); 70 } 71 } 72 73 private void jbInit() throws Exception { 74 this.getContentPane().setLayout(null); 75 this.setSize(new Dimension(505, 573)); 76 this.setTitle("Who is?"); 77 jLabel1.setText("Search Word"); 78 jLabel1.setBounds(new Rectangle(20, 30, 85, 30)); 79 name.setBounds(new Rectangle(105, 30, 180, 30)); 80 messageScrollPane.setBounds(new Rectangle(25, 120, 445, 365)); 81 search.setText("SEARCH"); 82 search.setBounds(new Rectangle(310, 30, 95, 30)); 83 search.addMouseListener(new java.awt.event.MouseAdapter() { 84 public void mouseClicked(MouseEvent e) { 85 search_mouseClicked(e); 86 } 87 }); 88 search.addKeyListener(new java.awt.event.KeyAdapter() { 89 public void keyPressed(KeyEvent e) { 90 search_keyPressed(e); 91 } 92 }); 93 search.addActionListener(new ActionListener() { 94 public void actionPerformed(ActionEvent e) { 95 search_actionPerformed(e); 96 } 97 }); 98 messagePane.setEditable(false); 99 messagePane.setEnabled(false); 100 this.getContentPane().add(search, null); 101 messageScrollPane.getViewport().add(messagePane, null); 102 this.getContentPane().add(messageScrollPane, null); 103 this.getContentPane().add(name, null); 104 this.getContentPane().add(jLabel1, null); 105 } 106 107 private void isUse(boolean use) { 108 name.setEnabled(use); 109 search.setEnabled(use); 110 messagePane.setEnabled(!use); 111 } 112 private void setMessage(String msg) { 113 messagePane.setText(messagePane.getText()+msg+" \n"); 114 } 115 private void action() { 116 //isUse(false); 117 Socket socket = null; 118 try{ 119 socket = new Socket("whois.internic.net",43); 120 PrintStream out = new PrintStream(new BufferedOutputStream(socket.getOutputStream())); 121 out.print(name.getText()); 122 out.print("\r\n"); 123 124 BufferedReader in = 125 new BufferedReader(new InputStreamReader(socket.getInputStream())); 126 String readLineStr = ""; 127 while((readLineStr = in.readLine()) != null) { 128 setMessage(readLineStr); 129 } 130 } catch (IOException ioe) { 131 setMessage(ioe.toString()); 132 } 133 } 134 private void search_actionPerformed(ActionEvent e) { 135 action(); 136 } 137 138 private void search_keyPressed(KeyEvent e) { 139 action(); 140 } 141 142 private void search_mouseClicked(MouseEvent e) { 143 action(); 144 } 145 }