Made updates in JSON format. Combined chat and tile queues into one UpdateQueue. Fixed UpdateQueue.

src/main/java/org/dynmap/UpdateQueue.java

@@ -0,0 +1,70 @@
+package org.dynmap;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.ListIterator;
+
+public class UpdateQueue {
+    public Object lock = new Object();
+    private LinkedList<Update> updateQueue = new LinkedList<Update>();
+
+    private static final int maxUpdateAge = 120000;
+
+    public void pushUpdate(Object obj) {
+        long now = System.currentTimeMillis();
+        long deadline = now - maxUpdateAge;
+        synchronized (lock) {
+            ListIterator<Update> i = updateQueue.listIterator(0);
+            while (i.hasNext()) {
+                Update u = i.next();
+                if (u.time < deadline || u.obj == obj)
+                    i.remove();
+            }
+            updateQueue.addLast(new Update(now, obj));
+        }
+    }
+
+    private ArrayList<Object> tmpupdates = new ArrayList<Object>();
+
+    public Object[] getUpdatedObjects(long since) {
+        long now = System.currentTimeMillis();
+        long deadline = now - maxUpdateAge;
+        Object[] updates;
+        synchronized (lock) {
+            tmpupdates.clear();
+            Iterator<Update> it = updateQueue.descendingIterator();
+            while (it.hasNext()) {
+                Update u = it.next();
+                if (u.time >= since) {
+                    // Tile is new.
+                    tmpupdates.add(u.obj);
+                } else if (u.time < deadline) {
+                    // Tile is too old, removing this one (will eventually decrease).
+                    it.remove();
+                    break;
+                } else {
+                    // Tile is old, but not old enough for removal.
+                    break;
+                }
+            }
+            
+            // Reverse output.
+            updates = new Object[tmpupdates.size()];
+            for (int i = 0; i < updates.length; i++) {
+                updates[i] = tmpupdates.get(updates.length-1-i);
+            }
+        }
+        return updates;
+    }
+
+    public class Update {
+        public long time;
+        public Object obj;
+
+        public Update(long time, Object obj) {
+            this.time = time;
+            this.obj = obj;
+        }
+    }
+}