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diff --git a/luni/src/main/java/java/util/Observable.java b/luni/src/main/java/java/util/Observable.java
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+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package java.util;
+
+
+/**
+ * Observable is used to notify a group of Observer objects when a change
+ * occurs. On creation, the set of observers is empty. After a change occurred,
+ * the application can call the {@link #notifyObservers()} method. This will
+ * cause the invocation of the {@code update()} method of all registered
+ * Observers. The order of invocation is not specified. This implementation will
+ * call the Observers in the order they registered. Subclasses are completely
+ * free in what order they call the update methods.
+ * 
+ * @see Observer
+ * 
+ * @since Android 1.0
+ */
+public class Observable {
+    
+    Vector<Observer> observers = new Vector<Observer>();
+
+    boolean changed = false;
+
+    /**
+     * Constructs a new {@code Observable} object.
+     * 
+     * @since Android 1.0
+     */
+    public Observable() {
+        super();
+    }
+
+    /**
+     * Adds the specified observer to the list of observers. If it is already
+     * registered, it is not added a second time.
+     * 
+     * @param observer
+     *            the Observer to add.
+     * @since Android 1.0
+     */
+    public synchronized void addObserver(Observer observer) {
+        if (observer == null) {
+            throw new NullPointerException();
+        }
+        if (!observers.contains(observer))
+            observers.addElement(observer);
+    }
+
+    /**
+     * Clears the changed flag for this {@code Observable}. After calling
+     * {@code clearChanged()}, {@code hasChanged()} will return {@code false}.
+     * 
+     * @since Android 1.0
+     */
+    protected synchronized void clearChanged() {
+        changed = false;
+    }
+
+    /**
+     * Returns the number of observers registered to this {@code Observable}.
+     * 
+     * @return the number of observers.
+     * @since Android 1.0
+     */
+    public synchronized int countObservers() {
+        return observers.size();
+    }
+
+    /**
+     * Removes the specified observer from the list of observers. Passing null
+     * won't do anything.
+     * 
+     * @param observer
+     *            the observer to remove.
+     * @since Android 1.0
+     */
+    public synchronized void deleteObserver(Observer observer) {
+        observers.removeElement(observer);
+    }
+
+    /**
+     * Removes all observers from the list of observers.
+     * 
+     * @since Android 1.0
+     */
+    public synchronized void deleteObservers() {
+        observers.setSize(0);
+    }
+
+    /**
+     * Returns the changed flag for this {@code Observable}.
+     * 
+     * @return {@code true} when the changed flag for this {@code Observable} is
+     *         set, {@code false} otherwise.
+     * @since Android 1.0
+     */
+    public synchronized boolean hasChanged() {
+        return changed;
+    }
+
+    /**
+     * If {@code hasChanged()} returns {@code true}, calls the {@code update()}
+     * method for every observer in the list of observers using null as the
+     * argument. Afterwards, calls {@code clearChanged()}.
+     * <p>
+     * Equivalent to calling {@code notifyObservers(null)}.
+     * </p>
+     * 
+     * @since Android 1.0
+     */
+    public void notifyObservers() {
+        notifyObservers(null);
+    }
+
+    /**
+     * If {@code hasChanged()} returns {@code true}, calls the {@code update()}
+     * method for every Observer in the list of observers using the specified
+     * argument. Afterwards calls {@code clearChanged()}.
+     * 
+     * @param data
+     *            the argument passed to {@code update()}.
+     * @since Android 1.0
+     */
+    @SuppressWarnings("unchecked")
+    public void notifyObservers(Object data) {
+        if (hasChanged()) {
+            // Must clone the vector in case deleteObserver is called
+            Vector<Observer> clone = (Vector<Observer>)observers.clone();
+            int size = clone.size();
+            for (int i = 0; i < size; i++) {
+                clone.elementAt(i).update(this, data);
+            }
+            clearChanged();
+        }
+    }
+
+    /**
+     * Sets the changed flag for this {@code Observable}. After calling
+     * {@code setChanged()}, {@code hasChanged()} will return {@code true}.
+     * 
+     * @since Android 1.0
+     */
+    protected synchronized void setChanged() {
+        changed = true;
+    }
+}