Make all member collections final.
[jSite2.git] / src / net / pterodactylus / jsite / core / NodeManager.java
index 71bb95d..9cdc60d 100644 (file)
@@ -19,6 +19,8 @@
 
 package net.pterodactylus.jsite.core;
 
+import java.beans.PropertyChangeEvent;
+import java.beans.PropertyChangeListener;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
@@ -29,29 +31,31 @@ import java.net.UnknownHostException;
 import java.util.ArrayList;
 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;
-import java.util.Set;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-import net.pterodactylus.fcp.highlevel.ConnectResult;
-import net.pterodactylus.fcp.highlevel.HighLevelCallback;
 import net.pterodactylus.fcp.highlevel.HighLevelClient;
+import net.pterodactylus.fcp.highlevel.HighLevelClientListener;
+import net.pterodactylus.fcp.highlevel.HighLevelException;
+import net.pterodactylus.fcp.highlevel.KeyGenerationResult;
+import net.pterodactylus.jsite.util.IdGenerator;
 import net.pterodactylus.util.io.Closer;
+import net.pterodactylus.util.logging.Logging;
+import net.pterodactylus.util.number.Hex;
 
 /**
  * TODO
  *
  * @author David ‘Bombe’ Roden <bombe@freenetproject.org>
- * @version $Id$
  */
-public class NodeManager {
+public class NodeManager implements Iterable<Node>, PropertyChangeListener, HighLevelClientListener {
 
        /** Logger. */
-       private static final Logger logger = Logger.getLogger(NodeManager.class.getName());
+       private static final Logger logger = Logging.getLogger(NodeManager.class.getName());
 
        /** The FCP client name. */
        private final String clientName;
@@ -62,17 +66,23 @@ public class NodeManager {
        /** Object used for synchronization. */
        private final Object syncObject = new Object();
 
+       /** Node listener support. */
+       private final NodeListenerSupport nodeListenerSupport = new NodeListenerSupport();
+
        /** All nodes. */
-       private List<Node> nodes = Collections.synchronizedList(new ArrayList<Node>());
+       private final List<Node> nodes = Collections.synchronizedList(new ArrayList<Node>());
 
-       /** All FCP connections. */
-       private Map<Node, HighLevelClient> nodeConnections = Collections.synchronizedMap(new HashMap<Node, HighLevelClient>());
+       /** Map from node ID to node. */
+       private final Map<String, Node> idNodes = Collections.synchronizedMap(new HashMap<String, Node>());
 
-       /** Keeps track of which connection is in use right now. */
-       private Set<HighLevelClient> usedConnections = Collections.synchronizedSet(new HashSet<HighLevelClient>());
+       /** All FCP connections. */
+       private final Map<Node, HighLevelClient> nodeClients = Collections.synchronizedMap(new HashMap<Node, HighLevelClient>());
 
        /** Maps nodes to high-level clients. */
-       private Map<HighLevelClient, Node> clientNodes = Collections.synchronizedMap(new HashMap<HighLevelClient, Node>());
+       private final Map<HighLevelClient, Node> clientNodes = Collections.synchronizedMap(new HashMap<HighLevelClient, Node>());
+
+       /** Collection of currently connected nodes. */
+       private final Set<Node> connectedNodes = Collections.synchronizedSet(new HashSet<Node>());
 
        /**
         * Creates a new FCP collector.
@@ -88,6 +98,30 @@ public class NodeManager {
        }
 
        //
+       // EVENT MANAGEMENT
+       //
+
+       /**
+        * Adds the given listener to the list of listeners.
+        *
+        * @param nodeListener
+        *            The listener to add
+        */
+       public void addNodeListener(NodeListener nodeListener) {
+               nodeListenerSupport.addListener(nodeListener);
+       }
+
+       /**
+        * Removes the given listener from the list of listeners.
+        *
+        * @param nodeListener
+        *            The listener to remove
+        */
+       public void removeNodeListener(NodeListener nodeListener) {
+               nodeListenerSupport.removeListener(nodeListener);
+       }
+
+       //
        // ACCESSORS
        //
 
@@ -112,6 +146,13 @@ public class NodeManager {
                return nodes.contains(node);
        }
 
+       /**
+        * {@inheritDoc}
+        */
+       public Iterator<Node> iterator() {
+               return nodes.iterator();
+       }
+
        //
        // ACTIONS
        //
@@ -123,6 +164,7 @@ public class NodeManager {
         *             if an I/O error occurs loading the nodes
         */
        public void load() throws IOException {
+               logger.log(Level.FINEST, "load()");
                File directoryFile = new File(directory);
                File nodeFile = new File(directoryFile, "nodes.properties");
                if (!nodeFile.exists() || !nodeFile.isFile() || !nodeFile.canRead()) {
@@ -140,6 +182,10 @@ public class NodeManager {
                List<Node> loadedNodes = new ArrayList<Node>();
                while (nodeProperties.containsKey("nodes." + ++nodeIndex + ".name")) {
                        String nodePrefix = "nodes." + nodeIndex;
+                       String nodeId = nodeProperties.getProperty(nodePrefix + ".id");
+                       if (nodeId == null) {
+                               nodeId = Hex.toHex(IdGenerator.generateId());
+                       }
                        String nodeName = nodeProperties.getProperty(nodePrefix + ".name");
                        if (!Verifier.verifyNodeName(nodeName)) {
                                logger.log(Level.WARNING, "invalid node name “" + nodeName + "”, skipping…");
@@ -164,14 +210,18 @@ public class NodeManager {
                                continue;
                        }
                        Node newNode = new Node();
+                       newNode.setId(nodeId);
                        newNode.setName(nodeName);
                        newNode.setHostname(nodeHostname);
                        newNode.setPort(nodePort);
                        loadedNodes.add(newNode);
                }
+               logger.log(Level.FINE, "loaded " + loadedNodes.size() + " nodes from config");
                synchronized (syncObject) {
                        nodes.clear();
-                       nodes.addAll(loadedNodes);
+                       for (Node node : loadedNodes) {
+                               addNode(node);
+                       }
                }
        }
 
@@ -182,6 +232,7 @@ public class NodeManager {
         *             if an I/O error occurs saving the nodes
         */
        public void save() throws IOException {
+               logger.log(Level.FINEST, "save()");
                File directoryFile = new File(directory);
                if (!directoryFile.exists()) {
                        if (!directoryFile.mkdirs()) {
@@ -190,8 +241,9 @@ public class NodeManager {
                }
                Properties nodeProperties = new Properties();
                int nodeIndex = -1;
-               for (Node node: nodes) {
+               for (Node node : nodes) {
                        String nodePrefix = "nodes." + ++nodeIndex;
+                       nodeProperties.setProperty(nodePrefix + ".id", node.getId());
                        nodeProperties.setProperty(nodePrefix + ".name", node.getName());
                        nodeProperties.setProperty(nodePrefix + ".hostname", node.getHostname());
                        nodeProperties.setProperty(nodePrefix + ".port", String.valueOf(node.getPort()));
@@ -207,41 +259,92 @@ public class NodeManager {
        }
 
        /**
-        * Adds a connection to the given node. The connection is made instantly so
-        * this method may block. If the node can not be connected, it will not be
-        * added to the list of nodes.
+        * Adds the given node to this manager.
         *
+        * @see #connect(Node)
         * @param node
         *            The node to connect to
-        * @return <code>true</code> if the connection to the node could be
-        *         established
-        * @throws UnknownHostException
-        *             if the hostname of the node can not be resolved
-        * @throws IOException
-        *             if an I/O error occurs connecting to the node
+        * @return <code>true</code> if the node was added, <code>false</code> if
+        *         the node was not added because it was already known
         */
-       public boolean addNode(Node node) throws UnknownHostException, IOException {
+       public boolean addNode(Node node) {
+               logger.log(Level.FINEST, "addNode(node=" + node + ")");
                if (nodes.contains(node)) {
-                       return true;
+                       logger.log(Level.WARNING, "was told to add already known node: " + node);
+                       return false;
                }
-               HighLevelClient highLevelClient = new HighLevelClient(clientName, node.getHostname(), node.getPort());
-               HighLevelCallback<ConnectResult> connectCallback = highLevelClient.connect();
-               ConnectResult connectResult = null;
-               while (connectResult == null) {
-                       try {
-                               connectResult = connectCallback.getResult();
-                       } catch (InterruptedException e) {
-                               /* ignore. */
+               node.addPropertyChangeListener(this);
+               HighLevelClient highLevelClient = new HighLevelClient(clientName);
+               nodes.add(node);
+               idNodes.put(node.getId(), node);
+               clientNodes.put(highLevelClient, node);
+               nodeClients.put(node, highLevelClient);
+               highLevelClient.addHighLevelClientListener(this);
+               nodeListenerSupport.fireNodeAdded(node);
+               return true;
+       }
+
+       /**
+        * Removes the given node from the node manager, disconnecting it if it is
+        * currently connected.
+        *
+        * @param node
+        *            The node to remove
+        */
+       public void removeNode(Node node) {
+               logger.log(Level.FINEST, "removeNode(node=" + node + ")");
+               synchronized (syncObject) {
+                       if (!nodes.contains(node)) {
+                               return;
+                       }
+                       if (nodeClients.containsKey(node)) {
+                               disconnect(node);
                        }
+                       nodes.remove(node);
+                       idNodes.remove(node.getId());
+                       node.removePropertyChangeListener(this);
+                       nodeListenerSupport.fireNodeRemoved(node);
+               }
+       }
+
+       /**
+        * Tries to establish a connection with the given node.
+        *
+        * @param node
+        *            The node to connect to
+        */
+       public void connect(Node node) {
+               logger.log(Level.FINEST, "connect(node=" + node + ")");
+               HighLevelClient highLevelClient;
+               highLevelClient = nodeClients.get(node);
+               if (highLevelClient == null) {
+                       logger.log(Level.WARNING, "was told to connect to unknown node: " + node);
+                       return;
+               }
+               try {
+                       highLevelClient.connect(node.getHostname(), node.getPort());
+               } catch (UnknownHostException uhe1) {
+                       nodeListenerSupport.fireNodeConnectionFailed(node, uhe1);
+               } catch (IOException ioe1) {
+                       nodeListenerSupport.fireNodeConnectionFailed(node, ioe1);
                }
-               if (connectResult.isConnected()) {
-                       synchronized (syncObject) {
-                               nodes.add(node);
-                               nodeConnections.put(node, highLevelClient);
-                               clientNodes.put(highLevelClient, node);
+       }
+
+       /**
+        * Disconnects the given node without removing it.
+        *
+        * @param node
+        *            The node to disconnect
+        */
+       public void disconnect(Node node) {
+               logger.log(Level.FINEST, "disconnect(node=" + node + ")");
+               synchronized (syncObject) {
+                       if (!nodes.contains(node)) {
+                               return;
                        }
+                       HighLevelClient highLevelClient = nodeClients.get(node);
+                       highLevelClient.disconnect();
                }
-               return connectResult.isConnected();
        }
 
        /**
@@ -250,49 +353,138 @@ public class NodeManager {
         * @return A list of all nodes
         */
        public List<Node> getNodes() {
-               return new ArrayList<Node>(clientNodes.values());
+               return Collections.unmodifiableList(nodes);
+       }
+
+       /**
+        * Returns the high-level client for a given node.
+        *
+        * @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 getHighLevelClient(Node node) {
+               return nodeClients.get(node);
+       }
+
+       /**
+        * Returns the node for a high-level client.
+        *
+        * @param highLevelClient
+        *            The high-level client to get the node for
+        * @return The node for the high-level client, or <code>null</code> if the
+        *         high-level client is not known
+        */
+       public Node getNode(HighLevelClient highLevelClient) {
+               return clientNodes.get(highLevelClient);
+       }
+
+       /**
+        * Returns the node identified by the given ID.
+        *
+        * @param id
+        *            The ID of the node
+        * @return The node with the given ID, or <code>null</code> if no such node
+        *         was found
+        */
+       Node getNode(String id) {
+               return idNodes.get(id);
+       }
+
+       /**
+        * Generates a new SSK key pair.
+        *
+        * @return An array with the private key at index <code>0</code> and the
+        *         public key at index <code>1</code>
+        * @throws IOException
+        *             if an I/O error occurs communicating with the node
+        * @throws JSiteException
+        *             if there is a problem with the node
+        */
+       public String[] generateKeyPair() throws IOException, JSiteException {
+               logger.log(Level.FINEST, "generateKeyPair()");
+               if (nodes.isEmpty()) {
+                       throw new NoNodeException("no node configured");
+               }
+               Node node = nodes.get(0);
+               HighLevelClient highLevelClient = nodeClients.get(node);
+               try {
+                       KeyGenerationResult keyGenerationResult = highLevelClient.generateKey().getResult();
+                       return new String[] { keyGenerationResult.getInsertURI(), keyGenerationResult.getRequestURI() };
+               } catch (HighLevelException hle1) {
+                       throw new BackendException(hle1);
+               } catch (InterruptedException e) {
+                       /* ignore. */
+               }
+               return null;
        }
 
        //
        // PRIVATE METHODS
        //
 
+       //
+       // INTERFACE HighLevelClientListener
+       //
+
        /**
-        * 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>
-        * @param markAsUsed
-        *            <code>true</code> to mark the connection as used before
-        *            returning it, <code>false</code> not to mark it
-        * @return An unused FCP connection, or <code>null</code> if no connection
-        *         could be found
+        * {@inheritDoc}
+        */
+       public void clientConnected(HighLevelClient highLevelClient) {
+               logger.log(Level.FINEST, "clientConnected(highLevelClient=" + highLevelClient + ")");
+               Node node = clientNodes.get(highLevelClient);
+               if (node == null) {
+                       logger.log(Level.WARNING, "got event for unknown client");
+                       return;
+               }
+               nodeListenerSupport.fireNodeConnected(node);
+       }
+
+       /**
+        * {@inheritDoc}
         */
-       @SuppressWarnings("unused")
-       private HighLevelClient findUnusedClient(boolean wait, boolean markAsUsed) {
+       public void clientDisconnected(HighLevelClient highLevelClient, Throwable throwable) {
+               logger.log(Level.FINEST, "clientDisconnected(highLevelClient=" + highLevelClient + ",throwable=" + throwable + ")");
                synchronized (syncObject) {
-                       HighLevelClient freeHighLevelClient = null;
-                       while (freeHighLevelClient == null) {
-                               for (HighLevelClient highLevelClient: nodeConnections.values()) {
-                                       if (!usedConnections.contains(highLevelClient)) {
-                                               freeHighLevelClient = highLevelClient;
-                                               break;
-                                       }
+                       Node node = clientNodes.get(highLevelClient);
+                       if (node == null) {
+                               logger.log(Level.WARNING, "got event for unknown client");
+                               return;
+                       }
+                       nodeListenerSupport.fireNodeDisconnected(node, throwable);
+               }
+       }
+
+       //
+       // INTERFACE PropertyChangeListener
+       //
+
+       /**
+        * {@inheritDoc}
+        */
+       public void propertyChange(PropertyChangeEvent propertyChangeEvent) {
+               Object eventSource = propertyChangeEvent.getSource();
+               if (eventSource instanceof Node) {
+                       String propertyName = propertyChangeEvent.getPropertyName();
+                       if ("hostname".equals(propertyName) || "port".equals(propertyName)) {
+                               Node node = (Node) eventSource;
+                               HighLevelClient highLevelClient = nodeClients.get(node);
+                               if (highLevelClient == null) {
+                                       logger.log(Level.WARNING, "got property change event for unknown node: " + node);
+                                       return;
                                }
-                               if (freeHighLevelClient != null) {
-                                       if (markAsUsed) {
-                                               usedConnections.add(freeHighLevelClient);
+                               if (highLevelClient.isConnected()) {
+                                       highLevelClient.disconnect();
+                                       try {
+                                               highLevelClient.connect(node.getHostname(), node.getPort());
+                                       } catch (UnknownHostException uhe1) {
+                                               nodeListenerSupport.fireNodeConnectionFailed(node, uhe1);
+                                       } catch (IOException ioe1) {
+                                               nodeListenerSupport.fireNodeConnectionFailed(node, ioe1);
                                        }
-                                       return freeHighLevelClient;
-                               }
-                               if (!wait) {
-                                       return null;
                                }
                        }
-                       /* we never get here, but the compiler doesn't realize. */
-                       return null;
                }
        }