Version 1.1

First version of basic update checker included
Event priorities for Move and Teleport listeners now HIGHEST

pom.xml

@@ -5,7 +5,7 @@
     <groupId>de.craftinc</groupId>
     <artifactId>CraftincBorderProtection</artifactId>
     <packaging>jar</packaging>
-    <version>1.0.3-1</version>
+    <version>1.1</version>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

src/main/java/de/craftinc/borderprotection/Messages.java

@@ -116,4 +116,14 @@ public class Messages
 
     public static String borderEnableDisableException =
             ChatColor.RED + "Error: Could not save border state on server. After the next reload this border state will be lost!";
+
+    public static String UpdateMessage( String newVersion, String curVersion )
+    {
+        return ChatColor.RED + "Craft Inc. BorderProtection: New version available!" + NEWLINE +
+               ChatColor.YELLOW + "Current version: " + ChatColor.WHITE + curVersion + NEWLINE +
+               ChatColor.YELLOW + "New version: " + ChatColor.WHITE + newVersion + NEWLINE +
+               ChatColor.YELLOW + "Please visit:" + NEWLINE +
+               ChatColor.AQUA + "http://dev.bukkit.org/server-mods/craftinc-borderprotection" + NEWLINE +
+               ChatColor.YELLOW + "to get the latest version!";
+    }
 }

src/main/java/de/craftinc/borderprotection/PlayerLoginListener.java

@@ -0,0 +1,50 @@
+/*  Craft Inc. BorderProtection
+    Copyright (C) 2013  Paul Schulze
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+package de.craftinc.borderprotection;
+
+import org.bukkit.Bukkit;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerLoginEvent;
+
+public class PlayerLoginListener implements Listener
+{
+    @EventHandler(priority = EventPriority.LOWEST)
+    public void onPlayerLogin( PlayerLoginEvent e )
+    {
+        final Player player = e.getPlayer();
+
+        if ( e.getPlayer().hasPermission("craftinc.borderprotection.update") )
+        {
+            if ( UpdateHelper.newVersionAvailable() )
+            {
+                // Schedule a task which delays 20 ticks (1 second) and then sends a message to the player
+                Bukkit.getScheduler().scheduleSyncDelayedTask(Plugin.getPlugin(), new Runnable()
+                {
+                    @Override
+                    public void run()
+                    {
+                        player.sendMessage(Messages.UpdateMessage(UpdateHelper.cachedLatestVersion,
+                                                                  UpdateHelper.getCurrentVersion()));
+                    }
+                }, 20L);
+            }
+        }
+    }
+}

src/main/java/de/craftinc/borderprotection/PlayerMoveListener.java

@@ -56,9 +56,15 @@ public class PlayerMoveListener implements Listener
     }
 
     @SuppressWarnings("unused")
-    @EventHandler(priority = EventPriority.NORMAL)
+    @EventHandler(priority = EventPriority.HIGHEST)
     public void onPlayerMove( PlayerMoveEvent e )
     {
+        // do nothing if the event is already cancelled
+        if (e.isCancelled())
+        {
+            return;
+        }
+
         // do nothing if player has the ignoreborders permission
         if ( e.getPlayer().hasPermission("craftinc.borderprotection.ignoreborders") )
         {

src/main/java/de/craftinc/borderprotection/PlayerTeleportListener.java

@@ -33,9 +33,15 @@ public class PlayerTeleportListener implements Listener
     }
 
     @SuppressWarnings("unused")
-    @EventHandler(priority = EventPriority.LOWEST)
+    @EventHandler(priority = EventPriority.HIGHEST)
     public void onPlayerMove( PlayerTeleportEvent e )
     {
+        // do nothing if the event is already cancelled
+        if (e.isCancelled())
+        {
+            return;
+        }
+
         // do nothing if player has the ignoreborders permission
         if ( e.getPlayer().hasPermission("craftinc.borderprotection.ignoreborders") )
         {

src/main/java/de/craftinc/borderprotection/Plugin.java

@@ -48,6 +48,7 @@ public class Plugin extends JavaPlugin
         BorderManager borderManager = new BorderManager();
         PlayerMoveListener playerMoveListener = new PlayerMoveListener(borderManager);
         PlayerTeleportListener playerTeleportListener = new PlayerTeleportListener(borderManager);
+        PlayerLoginListener playerLoginListener = new PlayerLoginListener();
 
         // commands
         Commands commandExecutor = new Commands(borderManager);
@@ -57,5 +58,6 @@ public class Plugin extends JavaPlugin
         PluginManager pm = this.getServer().getPluginManager();
         pm.registerEvents(playerMoveListener, this);
         pm.registerEvents(playerTeleportListener, this);
+        pm.registerEvents(playerLoginListener, this);
     }
 }

src/main/java/de/craftinc/borderprotection/UpdateHelper.java

@@ -0,0 +1,98 @@
+/*  Craft Inc. BorderProtection
+    Copyright (C) 2013  Paul Schulze
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+package de.craftinc.borderprotection;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+
+public class UpdateHelper
+{
+    /**
+     * The URL from which the Plugin tries to get the latest version.
+     */
+    @SuppressWarnings("FieldCanBeLocal")
+    private static final String updateUrl = "http://www.craftinc.de/plugins/update/craftinc-borderprotection";
+
+    /**
+     * The latest version which was seen on last check.
+     */
+    public static String cachedLatestVersion = null;
+
+
+    /**
+     * Gets the latest version from the updateURL and returns it as <code>String</code>.
+     *
+     * @return latest version as <code>String</code>.
+     */
+    @SuppressWarnings("StringBufferMayBeStringBuilder")
+    public static String getLatestVersion()
+    {
+        // StringBuffer is thread-safe. Don't know if this is really important here, but safe is safe :).
+        StringBuffer s = new StringBuffer();
+        try
+        {
+            URLConnection c = new URL(updateUrl).openConnection();
+            BufferedReader br = new BufferedReader(new InputStreamReader(c.getInputStream()));
+            String inputLine;
+            while ( ( inputLine = br.readLine() ) != null )
+            {
+                s.append(inputLine);
+            }
+            br.close();
+        }
+        catch ( MalformedURLException e )
+        {
+            Plugin.getPlugin().getLogger().warning("Could not check for latest version. Update URL is malformed.");
+        }
+        catch ( IOException e )
+        {
+            Plugin.getPlugin().getLogger().warning("Could not check for latest version. Update URL was not readable.");
+        }
+
+        // update cached latest version
+        cachedLatestVersion = s.toString();
+
+        return s.toString();
+    }
+
+
+    /**
+     * Gets the current version of this plugin directly from the plugin.yml version entry.
+     *
+     * @return current version as <code>String</code>.
+     */
+    public static String getCurrentVersion()
+    {
+        return Plugin.getPlugin().getDescription().getVersion();
+    }
+
+
+    /**
+     * Checks if a newer version is available.
+     *
+     * @return Boolean
+     */
+    public static Boolean newVersionAvailable()
+    {
+        return !getCurrentVersion().equals(getLatestVersion());
+    }
+
+}

src/main/resources/plugin.yml

@@ -33,3 +33,6 @@ permissions:
   craftinc.borderprotection.ignoreborders:
     default: op
     description: Allows to be everywhere on the map (ignoring the borders).
+  craftinc.borderprotection.update:
+    default: op
+    description: Allows to get notified on login, when a new update is available.