Misc. event utils.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@966589 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 200 insertions, 0 deletions

diff --git a/src/test/java/org/apache/commons/lang3/event/EventListenerSupportTest.java b/src/test/java/org/apache/commons/lang3/event/EventListenerSupportTest.java
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+++ b/src/test/java/org/apache/commons/lang3/event/EventListenerSupportTest.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 org.apache.commons.lang3.event;

+

+import junit.framework.TestCase;

+

+import java.awt.event.ActionEvent;

+import java.awt.event.ActionListener;

+import java.util.ArrayList;

+import java.util.List;

+

+public class EventListenerSupportTest extends TestCase

+{

+    public void testEventDispatchOrder()

+    {

+        EventListenerSupport<ActionListener> listenerSupport = EventListenerSupport.create(ActionListener.class);

+        final List<ActionListener> calledListeners = new ArrayList<ActionListener>();

+

+        final ActionListener listener1 = createListener(calledListeners);

+        final ActionListener listener2 = createListener(calledListeners);

+        listenerSupport.addListener(listener1);

+        listenerSupport.addListener(listener2);

+        listenerSupport.fire().actionPerformed(new ActionEvent("Hello", 0, "Hello"));

+        assertEquals(calledListeners.size(), 2);

+        assertSame(calledListeners.get(0), listener1);

+        assertSame(calledListeners.get(1), listener2);

+    }

+

+    public void testRemoveListenerDuringEvent()

+    {

+        final EventListenerSupport<ActionListener> listenerSupport = EventListenerSupport.create(ActionListener.class);

+        for (int i = 0; i < 10; ++i)

+        {

+            addDeregisterListener(listenerSupport);

+        }

+        assertEquals(listenerSupport.getListenerCount(), 10);

+        listenerSupport.fire().actionPerformed(new ActionEvent("Hello", 0, "Hello"));

+        assertEquals(listenerSupport.getListenerCount(), 0);

+    }

+

+    private void addDeregisterListener(final EventListenerSupport<ActionListener> listenerSupport)

+    {

+        listenerSupport.addListener(new ActionListener()

+        {

+            public void actionPerformed(ActionEvent e)

+            {

+                listenerSupport.removeListener(this);

+            }

+        });

+    }

+

+    private ActionListener createListener(final List<ActionListener> calledListeners)

+    {

+        return new ActionListener()

+        {

+            public void actionPerformed(ActionEvent e)

+            {

+                calledListeners.add(this);

+            }

+        };

+    }

+}

diff --git a/src/test/java/org/apache/commons/lang3/event/EventUtilsTest.java b/src/test/java/org/apache/commons/lang3/event/EventUtilsTest.java
new file mode 100644
index 000000000..3c4dd8d2d
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+++ b/src/test/java/org/apache/commons/lang3/event/EventUtilsTest.java
@@ -0,0 +1,123 @@
+/*

+ * 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 org.apache.commons.lang3.event;

+

+import junit.framework.TestCase;

+

+import java.beans.PropertyChangeEvent;

+import java.beans.PropertyChangeListener;

+import java.lang.reflect.InvocationHandler;

+import java.lang.reflect.Method;

+import java.lang.reflect.Proxy;

+import java.util.Map;

+import java.util.TreeMap;

+

+public class EventUtilsTest extends TestCase

+{

+    public void testAddEventListener()

+    {

+        final PropertyChangeSource src = new PropertyChangeSource();

+        EventCountingInvociationHandler handler = new EventCountingInvociationHandler();

+        PropertyChangeListener listener = handler.createListener(PropertyChangeListener.class);

+        assertEquals(0, handler.getEventCount("propertyChange"));

+        EventUtils.addEventListener(src, PropertyChangeListener.class, listener);

+        assertEquals(0, handler.getEventCount("propertyChange"));

+        src.setProperty("newValue");

+        assertEquals(1, handler.getEventCount("propertyChange"));

+    }

+

+    public void testBindEventsToMethod()

+    {

+        final PropertyChangeSource src = new PropertyChangeSource();

+        final EventCounter counter = new EventCounter();

+        EventUtils.bindEventsToMethod(counter, "eventOccurred", src, PropertyChangeListener.class);

+        assertEquals(0, counter.getCount());

+        src.setProperty("newValue");

+        assertEquals(1, counter.getCount());

+    }

+

+    public static class EventCounter

+    {

+        private int count;

+

+        public void eventOccurred()

+        {

+            count++;

+        }

+

+        public int getCount()

+        {

+            return count;

+        }

+    }

+

+    private static class EventCountingInvociationHandler implements InvocationHandler

+    {

+        private Map<String, Integer> eventCounts = new TreeMap<String, Integer>();

+

+        public <L> L createListener(Class<L> listenerType)

+        {

+            return listenerType.cast(Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),

+                    new Class[]{listenerType},

+                    this));

+        }

+

+        public int getEventCount(String eventName)

+        {

+            Integer count = eventCounts.get(eventName);

+            return count == null ? 0 : count;

+        }

+

+        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable

+        {

+            Integer count = eventCounts.get(method.getName());

+            if (count == null)

+            {

+                eventCounts.put(method.getName(), 1);

+            }

+            else

+            {

+                eventCounts.put(method.getName(), count + 1);

+            }

+            return null;

+        }

+    }

+

+    public static class PropertyChangeSource

+    {

+        private EventListenerSupport<PropertyChangeListener> listeners = EventListenerSupport.create(PropertyChangeListener.class);

+

+        private String property;

+

+        public void setProperty(String property)

+        {

+            String oldValue = this.property;

+            this.property = property;

+            listeners.fire().propertyChange(new PropertyChangeEvent(this, "property", "oldValue", property));

+        }

+

+        public void addPropertyChangeListener(PropertyChangeListener listener)

+        {

+            listeners.addListener(listener);

+        }

+

+        public void removePropertyChangeListener(PropertyChangeListener listener)

+        {

+            listeners.removeListener(listener);

+        }

+    }

+}