import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
+import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
/**
* TODO
- *
+ *
* @author David ‘Bombe’ Roden <bombe@freenetproject.org>
* @version $Id$
*/
-public class NodeManager implements HighLevelClientListener {
+public class NodeManager implements Iterable<Node>, HighLevelClientListener {
/** Logger. */
private static final Logger logger = Logging.getLogger(NodeManager.class.getName());
/**
* Creates a new FCP collector.
- *
+ *
* @param clientName
* The name of the FCP client
* @param directory
/**
* Adds the given listener to the list of listeners.
- *
+ *
* @param nodeListener
* The listener to add
*/
/**
* Removes the given listener from the list of listeners.
- *
+ *
* @param nodeListener
* The listener to remove
*/
}
/**
+ * Notifies all listeners that a node was added.
+ *
+ * @param node
+ * The node that was added.
+ */
+ private void fireNodeAdded(Node node) {
+ for (NodeListener nodeListener: nodeListeners) {
+ nodeListener.nodeAdded(node);
+ }
+ }
+
+ /**
+ * Notifies all listeners that a node was removed.
+ *
+ * @param node
+ * The node that was removed
+ */
+ private void fireNodeRemoved(Node node) {
+ for (NodeListener nodeListener: nodeListeners) {
+ nodeListener.nodeRemoved(node);
+ }
+ }
+
+ /**
* Notifies all listeners that the given node was connected.
- *
+ *
* @param node
* The node that is now connected
*/
/**
* Notifies all listeners that the given node was disconnected.
- *
+ *
* @param node
* The node that is now disconnected
* @param throwable
/**
* Returns the directory in which the nodes are stored.
- *
+ *
* @return The directory the nodes are stored in
*/
public String getDirectory() {
/**
* Checks whether the given node is already connected.
- *
+ *
* @param node
* The node to check
* @return <code>true</code> if the node is already connected,
return nodes.contains(node);
}
+ /**
+ * {@inheritDoc}
+ */
+ public Iterator<Node> iterator() {
+ return nodes.iterator();
+ }
+
//
// ACTIONS
//
/**
* Loads nodes.
- *
+ *
* @throws IOException
* if an I/O error occurs loading the nodes
*/
newNode.setPort(nodePort);
loadedNodes.add(newNode);
}
+ logger.fine("loaded " + loadedNodes.size() + " nodes from config");
synchronized (syncObject) {
nodes.clear();
nodes.addAll(loadedNodes);
}
+ for (Node node: nodes) {
+ fireNodeAdded(node);
+ }
}
/**
* Saves all configured nodes.
- *
+ *
* @throws IOException
* if an I/O error occurs saving the nodes
*/
/**
* Adds the given node to this manager.
- *
+ *
* @see #connect(Node)
* @param node
* The node to connect to
synchronized (syncObject) {
if (!nodes.contains(node)) {
nodes.add(node);
+ fireNodeAdded(node);
}
}
}
/**
* Removes the given node from the node manager, disconnecting it if it is
* currently connected.
- *
+ *
* @param node
* The node to remove
*/
if (nodeClients.containsKey(node)) {
disconnect(node);
}
+ fireNodeRemoved(node);
}
}
/**
* Tries to establish a connection with the given node.
- *
+ *
* @param node
* The node to connect to
*/
/**
* Disconnects the given node without removing it.
- *
+ *
* @param node
* The node to disconnect
*/
/**
* Returns a list of all nodes.
- *
+ *
* @return A list of all nodes
*/
public List<Node> getNodes() {
return Collections.unmodifiableList(nodes);
}
+ /**
+ * “Borrows” a high-level client for the given node. A borrowed client
+ * <strong>has</strong> to be returned to the node manager using
+ * {@link #returnHighLevelClient(HighLevelClient)} when it is no longer in
+ * use, i.e. after a message has been sent! This method will block until a
+ * high-level client for the given node is available.
+ *
+ * @param node
+ * The node to get a high-level client for
+ * @return The high-level client for a node, or <code>null</code> if the
+ * node was disconnected or removed
+ */
+ public HighLevelClient borrowHighLevelClient(Node node) {
+ synchronized (syncObject) {
+ if (!nodeClients.containsKey(node)) {
+ return null;
+ }
+ HighLevelClient highLevelClient = nodeClients.get(node);
+ while (nodeClients.containsKey(node) && usedConnections.contains(highLevelClient)) {
+ try {
+ syncObject.wait();
+ } catch (InterruptedException ie1) {
+ /* ignore. TODO - check. */
+ }
+ }
+ if (!nodeClients.containsKey(node)) {
+ return null;
+ }
+ usedConnections.add(highLevelClient);
+ return highLevelClient;
+ }
+ }
+
+ /**
+ * Returns a borrowed high-level client.
+ *
+ * @see #borrowHighLevelClient(Node)
+ * @param highLevelClient
+ * The high-level client to return
+ */
+ public void returnHighLevelClient(HighLevelClient highLevelClient) {
+ synchronized (syncObject) {
+ if (!clientNodes.containsKey(highLevelClient)) {
+ return;
+ }
+ usedConnections.remove(highLevelClient);
+ syncObject.notifyAll();
+ }
+ }
+
//
// PRIVATE METHODS
//
/**
* Finds a currently unused high-level client, optionally waiting until a
* client is free and marking it used.
- *
+ *
* @param wait
* <code>true</code> to wait for a free connection,
* <code>false</code> to return <code>null</code>
if (!wait) {
return null;
}
+ try {
+ syncObject.wait();
+ } catch (InterruptedException e) {
+ /* ignore, just re-check. */
+ }
}
/* we never get here, but the compiler doesn't realize. */
return null;
* {@inheritDoc}
*/
public void clientDisconnected(HighLevelClient highLevelClient, Throwable throwable) {
- logger.log(Level.FINER, "clientDisconnected(c=" + highLevelClient + ",t=" + throwable +")");
+ logger.log(Level.FINER, "clientDisconnected(c=" + highLevelClient + ",t=" + throwable + ")");
synchronized (syncObject) {
Node node = clientNodes.remove(highLevelClient);
if (node == null) {
return;
}
nodeClients.remove(node);
+ usedConnections.remove(highLevelClient);
fireNodeDisconnected(node, throwable);
}
}