Java by API/java.net/Socket

new Socket(InetAddress address, int port) throws IOException

  

import java.net.InetAddress;
import java.net.Socket;
public class Main {
  public static void main(String[] argv) throws Exception {
    InetAddress addr = InetAddress.getByName("java.sun.ru");
    int port = 80;
    Socket socket = new Socket(addr, port);
  }
}

Socket: connect(SocketAddress endpoint, int timeout) throws IOException

  
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
public class Main {
  public static void main(String[] argv) throws Exception {
    InetAddress addr = InetAddress.getByName("java.sun.ru");
    int port = 80;
    SocketAddress sockaddr = new InetSocketAddress(addr, port);
    Socket sock = new Socket();
    int timeoutMs = 2000; // 2 seconds
    sock.connect(sockaddr, timeoutMs);
  }
}

Socket: getInputStream() throws IOException

  
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
class Whois {
  public static void main(String args[]) throws Exception {
    int c;
    Socket s = new Socket("internic.net", 43);
    InputStream in = s.getInputStream();
    OutputStream out = s.getOutputStream();
    String str = "asdfasdfasdf\n";
    byte buf[] = str.getBytes();
    out.write(buf);
    while ((c = in.read()) != -1) {
      System.out.print((char) c);
    }
    s.close();
  }
}

Socket: getLocalSocketAddress()

 
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
public class MainClass {
  public static void main(String[] args) throws Exception {
    String serverName = args[0];
    int port = Integer.parseInt(args[1]);
    try {
      System.out.println("Connecting to " + serverName + " on port " + port);
      Socket client = new Socket(serverName, port);
      System.out.println("Just connected to " + client.getRemoteSocketAddress());
      OutputStream outToServer = client.getOutputStream();
      DataOutputStream out = new DataOutputStream(outToServer);
      out.writeUTF("Hello from " + client.getLocalSocketAddress());
      InputStream inFromServer = client.getInputStream();
      DataInputStream in = new DataInputStream(inFromServer);
      System.out.println("Server says " + in.readUTF());
      client.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}

Socket: getOutputStream() throws IOException

  
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
class Whois {
  public static void main(String args[]) throws Exception {
    int c;
    Socket s = new Socket("internic.net", 43);
    InputStream in = s.getInputStream();
    OutputStream out = s.getOutputStream();
    String str = "asdfasdfasdf\n";
    byte buf[] = str.getBytes();
    out.write(buf);
    while ((c = in.read()) != -1) {
      System.out.print((char) c);
    }
    s.close();
  }
}

Socket: getRemoteSocketAddress()

 
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
public class MainClass {
  public static void main(String[] args) throws Exception {
    String serverName = args[0];
    int port = Integer.parseInt(args[1]);
    try {
      System.out.println("Connecting to " + serverName + " on port " + port);
      Socket client = new Socket(serverName, port);
      System.out.println("Just connected to " + client.getRemoteSocketAddress());
      OutputStream outToServer = client.getOutputStream();
      DataOutputStream out = new DataOutputStream(outToServer);
      out.writeUTF("Hello from " + client.getLocalSocketAddress());
      InputStream inFromServer = client.getInputStream();
      DataInputStream in = new DataInputStream(inFromServer);
      System.out.println("Server says " + in.readUTF());
      client.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}

Socket: readUTF() and writeUTF(String str)

 
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.Socket;
public class MainClass extends Thread {
  public MainClass() throws IOException {
  }
  public void run() {
    try {
      Socket socket = new Socket("127.0.0.1", 2000);
      DataInputStream in = new DataInputStream(socket.getInputStream());
      BufferedReader console = new BufferedReader(new InputStreamReader(System.in));
      DataOutputStream out = new DataOutputStream(socket.getOutputStream());
      while (true) {
        System.out.print("Enter response: ");
        String response = console.readLine();
        out.writeUTF(response);
        String message = in.readUTF();
        System.out.println(message);
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
  public static void main(String[] args) {
    try {
      Thread t = new MainClass();
      t.start();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}