| package com.javaconcepts.networking;import java.io.InputStream;import java.io.OutputStream;import java.net.Socket;public class SocketDemo { /* * The "ServerSocket" class is for the servers and they act as "listeners" in * the TCP/IP protocol. It is used to create servers that listen for either * local or remote client programs to connect to them on published ports. When * we create a ServerSocket, it will register itself with the system as having * an interest in client connections. */ /* * The "Socket" class is for the clients. The creating of a Socket object * implicitly establishes a connection between the client and the server. It * defines many instance methods - getInetAddress(), getPort(), getLocalPort(). * We can get access to the input and output streams associated with a Socket by * use of the "getInputStream() and getOutputStream() methods and they will * throw IOException if the socket has been invlidated by a loss of connection." * Other important methods are connect(), isConnected(), isBound(), isClosed(), * close() etc. */ public static void main(String[] args) throws Exception { int c; // create a socket connected to internic.net, port 43 // BUG: CWE-319: Cleartext Transmission of Sensitive Information// Socket s = new Socket("whois.internic.net", 43);// FIXED: // obtain input and output streams InputStream in = s.getInputStream(); OutputStream out = s.getOutputStream(); // construct a request string String str = (args.length == 0 ? "OraclePressBooks.com" : args[0]) + "\n"; // convert to bytes byte[] buf = str.getBytes(); // send request out.write(buf); // read and display reponse while ((c = in.read()) != -1) { System.out.print((char) c); } s.close(); }} |