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Diffstat (limited to 'src/main/java/derms/replica/replica2/SwapResource.java')
-rw-r--r--src/main/java/derms/replica/replica2/SwapResource.java262
1 files changed, 0 insertions, 262 deletions
diff --git a/src/main/java/derms/replica/replica2/SwapResource.java b/src/main/java/derms/replica/replica2/SwapResource.java
deleted file mode 100644
index bcdd222..0000000
--- a/src/main/java/derms/replica/replica2/SwapResource.java
+++ /dev/null
@@ -1,262 +0,0 @@
-package derms.replica.replica2;
-
-import java.io.IOException;
-import java.io.Serializable;
-import java.net.*;
-import java.util.NoSuchElementException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.logging.Logger;
-
-class SwapResource {
- static final int port = 5560;
- static final int bufSize = 4096;
-
- static class Client {
- private CoordinatorID cid;
- private ResourceID oldRID;
- private ResourceID newRID;
-
- Client(CoordinatorID cid, ResourceID oldRID, ResourceID newRID) {
- this.cid = cid;
- this.oldRID = oldRID;
- this.newRID = newRID;
- }
-
- Response sendRequest(InetAddress serverAddr) throws IOException {
- Request request = new Request(cid, oldRID, newRID);
- DatagramSocket sock;
- try {
- sock = new DatagramSocket();
- } catch (Exception e) {
- throw new IOException("Swap Resource Client: failed to open socket: "+e.getMessage());
- }
-
- DatagramPacket requestPkt;
- try {
- requestPkt = ObjectPacket.create(request, new InetSocketAddress(serverAddr, port));
- } catch (IOException e) {
- sock.close();
- throw new IOException("Swap Resource Client: failed to create request: "+e.getMessage());
- }
-
- sock.send(requestPkt);
-
- byte[] buf = new byte[bufSize];
- DatagramPacket responsePkt = new DatagramPacket(buf, buf.length);
- try {
- sock.receive(responsePkt);
- } catch (Exception e) {
- sock.close();
- throw new IOException("Swap Resource Client: error receiving from server: "+e.getMessage());
- }
-
- try {
- return ObjectPacket.deserialize(responsePkt, Response.class);
- } catch (IOException e) {
- throw new IOException("Swap Resource Client: failed to deserialize response: "+e.getMessage());
- } finally {
- sock.close();
- }
- }
- }
-
- static class Server implements Runnable {
- private InetAddress localAddr;
- private Resources resources;
- private Servers servers;
- private ExecutorService pool;
- private Logger log;
-
- Server(InetAddress localAddr, Resources resources, Servers servers) throws IOException {
- this.localAddr = localAddr;
- this.resources = resources;
- this.servers = servers;
- pool = Executors.newWorkStealingPool();
- this.log = DermsLogger.getLogger(this.getClass());
- }
-
- @Override
- public void run() {
- DatagramSocket sock = null;
- try {
- sock = new DatagramSocket(port, localAddr);
- } catch (Exception e) {
- log.severe("Failed to bind socket to "+localAddr+": "+e.getMessage());
- return;
- }
- log.info("Listening on "+localAddr+":"+port);
-
- DatagramPacket requestPkt = new DatagramPacket(new byte[bufSize], bufSize);
-
- try {
- for (;;) {
- try {
- sock.receive(requestPkt);
- } catch (Exception e) {
- log.warning("Error receiving from socket: "+e.getMessage());
- continue;
- }
- log.fine("Got request");
-
- Request request = null;
- try {
- request = ObjectPacket.deserialize(requestPkt, Request.class);
- } catch (IOException e) {
- log.warning("Failed to deserialize request: "+e.getMessage());
- continue;
- }
-
- SocketAddress client = requestPkt.getSocketAddress();
- try {
- RequestHandler handler = new RequestHandler(request, client, resources, servers);
- pool.execute(handler);
- } catch (IOException e) {
- log.warning("Failed to create request handler: "+e.getMessage());
- continue;
- }
- }
- } finally {
- sock.close();
- }
- }
- }
-
- private static class Request implements Serializable {
- private CoordinatorID cid;
- private ResourceID oldRID;
- private ResourceID newRID;
-
- private Request(CoordinatorID cid, ResourceID oldRID, ResourceID newRID) {
- this.cid = cid;
- this.oldRID = oldRID;
- this.newRID = newRID;
- }
- }
-
- private static class RequestHandler implements Runnable {
- private Request request;
- private SocketAddress client;
- private Resources resources;
- private Servers servers;
- private Logger log;
-
- private RequestHandler(Request request, SocketAddress client, Resources resources, Servers servers) throws IOException {
- this.request = request;
- this.client = client;
- this.resources = resources;
- this.servers = servers;
- this.log = DermsLogger.getLogger(this.getClass());
- }
-
- @Override
- public void run() {
- Response response = swapResources();
-
- DatagramSocket sock;
- try {
- sock = new DatagramSocket();
- } catch (Exception e) {
- log.severe("failed to open socket: "+e.getMessage());
- return;
- }
-
- DatagramPacket pkt;
- try {
- pkt = ObjectPacket.create(response, client);
- } catch (IOException e) {
- log.severe("failed to create response: "+e.getMessage());
- sock.close();
- return;
- }
-
- try {
- sock.send(pkt);
- } catch (Exception e) {
- log.severe("failed to send response: "+e.getMessage());
- } finally {
- sock.close();
- }
- }
-
- private Response swapResources() {
- try {
- Resource resource = resources.getByID(request.oldRID);
- synchronized (resource) {
- if (!resource.borrower.equals(request.cid)) {
- return new Response(Response.Status.NOT_BORROWED, "resource "+request.oldRID+" not borrowed by "+request.cid);
- }
- try {
- acquireNewResource(resource.borrowDuration);
- returnOldResource(resource);
- return new Response(Response.Status.SUCCESS, request.cid+" success fully swapped "+request.oldRID+" for "+request.newRID);
- } catch (UnknownHostException e) {
- return new Response(Response.Status.UNKNOWN_HOST, e.getMessage());
- } catch (IOException e) {
- return new Response(Response.Status.FAILURE, e.getMessage());
- } catch (CannotBorrow e) {
- return new Response(Response.Status.CANNOT_BORROW, e.getMessage());
- }
- }
- } catch (NoSuchElementException e) {
- return new Response(Response.Status.NO_SUCH_RESOURCE, "no such resource "+request.oldRID);
- }
- }
-
- private void acquireNewResource(int borrowDuration) throws UnknownHostException, IOException, CannotBorrow {
- RequestResource.Client requestClient = new RequestResource.Client(request.cid, request.newRID, borrowDuration);
- City city = new City(request.newRID.city);
- InetAddress requestResourceServer = servers.get(city);
- if (requestResourceServer == null) {
- throw new UnknownHostException(city.toString());
- }
- RequestResource.Response response = requestClient.sendRequest(requestResourceServer);
- // TODO: make exception handling more granular---pass through status from Request.
- if (response.status != RequestResource.Response.Status.SUCCESS) {
- throw new CannotBorrow(request.cid, request.newRID, response.message);
- }
- }
-
- private void returnOldResource(Resource r) {
- r.isBorrowed = false;
- r.borrower = new CoordinatorID();
- r.borrowDuration = -1;
- }
- }
-
- static class Response implements Serializable {
- Status status;
- String message;
-
- private Response(Status status, String message) {
- this.status = status;
- this.message = message;
- }
-
- enum Status {
- SUCCESS,
- FAILURE,
- NO_SUCH_RESOURCE,
- NOT_BORROWED,
- CANNOT_BORROW,
- UNKNOWN_HOST
- }
- }
-
- private static class CannotBorrow extends Exception {
- CoordinatorID attemptedBorrower;
- ResourceID rid;
- String message;
-
- private CannotBorrow(CoordinatorID attemptedBorrower, ResourceID rid, String message) {
- this.attemptedBorrower = attemptedBorrower;
- this.rid = rid;
- this.message = message;
- }
-
- @Override
- public String getMessage() {
- return attemptedBorrower+" failed to borrow "+rid+": "+message;
- }
- }
-} \ No newline at end of file
generated by cgit v1.2.3 (git 2.25.1) at 2026-04-19 05:08:33 +0000