src/zutil/OneInstanceNetwork.java

@@ -0,0 +1,74 @@
+package zutil;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+import zutil.io.MultiPrintStream;
+
+/**
+ * This class checks if the app is alredy running
+ * by Locking a port
+ * 
+ * @author Ziver Koc
+ */
+public class OneInstanceNetwork extends Thread implements OneInstance{
+	private int port;
+	
+	/**
+	 * Creates a One App objekt
+	 * 
+	 * @param port The port to lock
+	 */
+	public OneInstanceNetwork(int port){
+		this.port = port;
+	}
+	
+	/**
+	 * Starts the port lock
+	 * 
+	 * @return Always true
+	 */
+	public boolean lockApp(){
+		this.start();
+		return true;
+	}
+	
+	/**
+	 * he port lock thread 
+	 * should not be cald outside the class
+	 */
+	public void run() {
+		ServerSocket serverSocket = null;
+		Socket clientSocket = null;
+		try {
+			// Create the server socket
+			serverSocket = new ServerSocket(port, 1);
+			while (true) {
+				// Wait for a connection
+				clientSocket = serverSocket.accept();
+				clientSocket.close();
+			}
+		}
+		catch (IOException ioe) {
+			MultiPrintStream.out.println("Error in JustOneServer: " + ioe);
+		}
+	}
+
+	/**
+	 * Checks if the port is locked
+	 * 
+	 * @return True if port is locked else false
+	 */
+	public boolean check() {
+		try {
+			Socket clientSocket = new Socket("localhost", port);
+			MultiPrintStream.out.println("Already running!!!");
+			clientSocket.close();
+			return true;
+		}
+		catch (Exception e) {
+			return false;
+		}
+	}
+}