some improvements

ws2012/P2P/uebungen/4/src/network/Network.java

@@ -1,11 +1,23 @@
 package network;
 
+import peer.Peer;
+
 public class Network {
 
 	
 	//grow a network: Starting with one peer, repeatedly let peers spawn or leave at random
 	public static void main(String[] args) {
 		
+		Peer a = new Peer("A");
+		System.out.println("Spawn B:");
+		a.spawn("B");
+		System.out.println("Spawn C:");
+		a.spawn("C");
+		System.out.println("Spawn D:");
+		a.spawn("D");
+ 
+		System.out.println("Leave A:");
+		a.leave();
 	}
 	
 	

ws2012/P2P/uebungen/4/src/peer/Node.java

@@ -1,19 +1,28 @@
 package peer;
 
+import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
 
 public class Node {
 	
+<<<<<<< HEAD
 	// node id must be unique! id = IP of peer ?!?
 	// -> Should be unique if we don't consider peers behind a NAT.
 	private int id;
 
 	private List<Node> neighbours;
+=======
+	private int id; // node id must be unique! id = IP of peer ?!?
+					//-> Should be unique if we don't consider peers behind a NAT.
+	private String name;
 	
-	public Node(int id, List<Node> neighbours){
-		this.id 			= id;
-		this.neighbours 	= neighbours;
+	private List<Node> neighbours = new ArrayList<Node>();
+>>>>>>> some improvements
+	
+	public Node(int id, String name){
+		this.id = id;
+		this.name = name;
 	}
 	
 	
@@ -23,7 +32,21 @@ public class Node {
 	 * @param neighbour
 	 */
 	public void addSingleNeighbour(Node neighbour){
-		this.neighbours.add(neighbour);
+		
+		Iterator<Node> it = this.neighbours.iterator();
+		
+		if(!it.hasNext()){ //list of neighbours is empty
+			this.neighbours.add(neighbour);
+		}else{
+			//check if neighbour is already in list
+			while(it.hasNext()){
+				if(it.next().getId() == neighbour.getId()){
+					return;
+				}
+			}
+			this.neighbours.add(neighbour);
+		}
+		printInfos();
 	}
 	
 	/**
@@ -34,14 +57,26 @@ public class Node {
 	public void addMultiNeighbours(List<Node> neighbours){
 		Iterator<Node> it = neighbours.iterator();
 		while(it.hasNext()){
-			this.neighbours.add(it.next());
+			addSingleNeighbour(it.next());
 		}
 	}
 	
+	//checks if actual node has neighbour with given id -> remove it
+		public void removeNeighbour(Node node){
+			for(int i = 0; i < this.neighbours.size(); i++){
+				Node tmp = this.neighbours.get(i);
+				if(tmp.id == node.id){
+					this.neighbours.remove(i);
+				}
+			}
+			printInfos();
+		}
+	
 	public boolean hasNeighbours(){
 		return (this.neighbours.size() > 0);
 	}
 	
+<<<<<<< HEAD
 	/**
 	 * checks if actual node has neighbour with given id
 	 * 
@@ -54,7 +89,33 @@ public class Node {
 			if(tmp.id == id){
 				return true;
 			}
-		}
-		return false;
+=======
+	public int getId(){
+		return this.id;
 	}
-}
+	
+	public List<Node> getNeighbours(){
+		return this.neighbours;
+	}
+	
+	
+	//for testing
+	public void printInfos(){
+		System.out.print("Name: " + this.name + ", Neighbours: ");
+		for(int i = 0; i < this.neighbours.size(); i++){
+			System.out.print(this.neighbours.get(i).name + ", ");
+>>>>>>> some improvements
+		}
+		System.out.println();
+	}
+<<<<<<< HEAD
+}
+=======
+	
+	
+	
+	
+	
+
+}
+>>>>>>> some improvements

ws2012/P2P/uebungen/4/src/peer/Peer.java

@@ -1,9 +1,13 @@
 package peer;
 
+import java.util.List;
+import java.util.Random;
+
 
 public class Peer {
 
 	private Node node;
+<<<<<<< HEAD
 
 	/**
 	 * Create another peer, mutually link creator and spawn.
@@ -18,6 +22,41 @@ public class Peer {
 	 */
 	public void leave() {
 
+=======
+	
+	
+	public Peer(String name){
+		this.node = new Node(new Random().nextInt(), name);
+	}
+	
+	public Node getNode(){
+		return this.node;
+	}
+	
+	
+	//create another peer, mutually link creator and spawn
+	public void spawn(String name){
+		//create a new node
+		Node spawnNode = new Node(new Random().nextInt(), name);
+		spawnNode.addSingleNeighbour(this.node);
+		
+		//link new node to actual node
+		this.node.addSingleNeighbour(spawnNode);
+		
+	}
+	
+	
+	//circularly link all neighbours, remove itself form all neighbours and exit
+	public void leave(){
+		List<Node> neighbours = this.node.getNeighbours();
+		
+		for(int i = 0; i < neighbours.size(); i++){
+			//add all neighbours
+			neighbours.get(i).addMultiNeighbours(neighbours);
+			//remove itself
+			neighbours.get(i).removeNeighbour(this.node); 
+		}
+>>>>>>> some improvements
 	}