@GET
@Path("/predecessor-of/{param}")
public NodeInfo findPredecessor(@PathParam("param") int id) {
// Checks if the id searched for is greater/equal to this nodes ID, and smaller/equal than
// successors nodes ID, in which case this node should be returned
// if(id >= this.id && id < successorID()).
if (this.id < id && successor.getID() >= id) {
return thisNode;
}
// Check if successor is smaller than this node ID, and if searched ID is in between. If so
// we're crossing the '0' line, and this node is predecessor
// if(succID < this.id)
// if(id > this.id || id < succID
else if (successor.getID() < this.id) { // we are the highest id in the hood
if (this.id < id || successor.getID() >= id) {
return thisNode;
}
}
// Special case, only this node in network
else if (successor.getID() == this.id) {
return thisNode;
}
// System.out.println(this.id + ": Routed to node " + successor.getID());
// return requestSender.findIdPredecessor(successor, id);
// System.out.println(this.id + ": Routed to node " + closestPreceedingFinger(id).getID());
return requestSender.findIdPredecessor(closestPreceedingFinger(id), id);
}
// Updates the finger table with the {param} ID node as potential finger
@PUT
@Path("/update/{param}")
@Produces(MediaType.APPLICATION_JSON)
public Response updateFingerTable(NodeInfo n, @PathParam("param") int fingerNr) {
if (isInRange(n.getID(), thisNode.getID(), fingers[fingerNr].getID())) {
fingers[fingerNr] = n;
requestSender.updateFingerTable(predecessor, n, fingerNr);
}
return Response.status(200).entity(n).build();
}
public void takeResponsibilities() {
String responsible = requestSender.takePhotonResponsibility(successor, thisNode.getID());
if (responsible.equals("true")) {
System.out.println("Becoming new responsible node");
photonData = requestSender.getPhotonData(successor).getList();
updatePhoton(thisNode); // Begin being the responsible node
}
}
public NodeInfo closestPreceedingFinger(int id) {
for (int i = 15; i >= 0; i--) {
int fID = fingers[i].getID();
if (isInRange(fID, thisNode.getID(), id)) {
return fingers[i];
}
}
// Returning this node here means something went wrong with the node routing, and it will loop
// forever
System.out.println("Shouldn't happen");
return thisNode;
}
// Receive data from node responsible for data, for replication purposes
@POST
@Path("/sendPhotonData")
@Consumes(MediaType.APPLICATION_JSON)
public Response replicatePhotonData(PhotonData pd) {
if (photonData.isEmpty()) {
photonData = requestSender.getPhotonData(predecessor).getList();
} else {
photonData.add(pd);
}
replicatedValue = pd.replica--;
if (pd.replica > 0) {
if (successor.getID() != thisNode.getID()) {
requestSender.sendPhotonData(successor, pd);
}
}
// System.out.println(thisNode.getPort() + " recieved bunch of data: " + photonData.toString());
return Response.status(200).entity(pd).build();
}
public void initFingerTable(String ip, int port) {
// Set first finger, which is just immediate successor
fingers[0] = successor;
// Fill finger table
NodeInfo recentFinger = fingers[0];
int nextFingerID = 0;
for (int i = 1; i < 16; i++) {
nextFingerID = (thisNode.getID() + (int) Math.pow(2, i)) % (int) Math.pow(2, 16);
if (isInRange(nextFingerID, thisNode.getID(), recentFinger.getID())) {
fingers[i] = recentFinger;
}
// ID searched is higher than our current finger, so we ask it to find the next one for us.
else {
recentFinger = requestSender.findIdSuccessor(ip, port, nextFingerID);
fingers[i] = recentFinger;
}
}
}
private void updateOthers() {
requestSender.updateNodeSuccessor(predecessor, thisNode);
requestSender.updateNodePredecessor(successor, thisNode);
int preceedingNodeID;
for (int i = 0; i < 16; i++) {
preceedingNodeID =
((int) Math.pow(2, 16) + thisNode.getID() - (int) Math.pow(2, i)) % (int) Math.pow(2, 16);
NodeInfo p = findPredecessor(preceedingNodeID);
requestSender.updateFingerTable(p, thisNode, i);
}
}
// Finds the responsible node for the photon and updates it and the successor of it
public void findResponsibleNode() {
String photonJson = requestSender.findSpark();
try {
JSONObject temp = new JSONObject(photonJson);
JSONObject temp2 = temp.getJSONObject("coreInfo");
String deviceID = temp2.getString("deviceID");
int convertedID = Key.generate16BitsKey(deviceID);
NodeInfo responsible = findSuccessor(convertedID);
// NodeInfo resposibleSuccessor = requestSender.getNodeSuccessor(responsible);
requestSender.updatePhoton(responsible);
// requestSender.updatePhoton(resposibleSuccessor);
System.out.println("PhotonID: " + convertedID);
System.out.println("Responsible is:\n" + responsible.getID());
} catch (JSONException e) {
e.printStackTrace();
}
}
public void join(String ip, int port) { // n is existing known node to bootstrap into the network
System.out.println(this.port + ": Joining");
// Initialize own successor/predecessors
successor = requestSender.findIdSuccessor(ip, port, thisNode.getID());
// No ID needed for path
predecessor = requestSender.getNodePredecessor(successor);
takeResponsibilities();
// createTimerCheckPredecessor();
initFingerTable(ip, port);
listenToRequests();
System.out.println(this.port + ": Listening");
// Update successors and predecessor with this node
updateOthers();
System.out.println("Join complete!");
System.out.println("Check the node at status at " + thisNode.getIndex());
}
public void printTable() {
for (NodeInfo n : fingers) {
System.out.println(n.getIP() + ":" + n.getPort() + "/" + n.getID());
}
}