svn commit: r1596012 - in /commons/proper/configuration/trunk/src: main/java/org/apache/commons/configuration/event/EventType.java test/java/org/apache/commons/configuration/event/TestEventType.java

[oh...@apache.org]

Author: oheger
Date: Mon May 19 19:52:21 2014
New Revision: 1596012

URL: http://svn.apache.org/r1596012
Log:
Initial implementation of EventType.

An EventType instance represents a specific type of an event generated by the
[configuration] library. It also stores a super event type, allowing events to
form a hierarchical structure.

Added:
    commons/proper/configuration/trunk/src/main/java/org/apache/commons/configuration/event/EventType.java
    commons/proper/configuration/trunk/src/test/java/org/apache/commons/configuration/event/TestEventType.java

Added: commons/proper/configuration/trunk/src/main/java/org/apache/commons/configuration/event/EventType.java
URL: http://svn.apache.org/viewvc/commons/proper/configuration/trunk/src/main/java/org/apache/commons/configuration/event/EventType.java?rev=1596012&view=auto
==============================================================================
--- commons/proper/configuration/trunk/src/main/java/org/apache/commons/configuration/event/EventType.java (added)
+++ commons/proper/configuration/trunk/src/main/java/org/apache/commons/configuration/event/EventType.java Mon May 19 19:52:21 2014
@@ -0,0 +1,104 @@
+/*
+ * 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.configuration.event;
+
+/**
+ * <p>
+ * A class representing an event type.
+ * </p>
+ * <p>
+ * The events produced by <em>Commons Configuration</em> all have a specific
+ * type. The event type can be used to determine the meaning of a specific
+ * event. It also acts as filter criterion when event listeners are registered.
+ * The listener is then called only for events of this type or derived types.
+ * The events in this library form a natural hierarchy with base types and more
+ * specialized types. By specifying an appropriate event type at listener
+ * registration time, it can be determined on a fine-granular basis which events
+ * are propagated to the listener.
+ * </p>
+ * <p>
+ * Note: Users familiar with JavaFX probably recognize this approach to event
+ * handling. It allows for generic event listener interfaces and a natural
+ * selection of events to be processed.
+ * </p>
+ *
+ * @version $Id$
+ * @since 2.0
+ * @param <T> the event associated with this type
+ */
+public class EventType<T>
+{
+    /** Constant for the format used by toString(). */
+    private static final String FMT_TO_STRING = "%s [ %s ]";
+
+    /** Stores the super type of this type. */
+    private final EventType<? super T> superType;
+
+    /** A name for this event type. */
+    private final String name;
+
+    /**
+     * Creates a new instance of {@code EventType} and initializes it with the
+     * super type and a type name. If no super type is specified, this is the
+     * root event type.
+     *
+     * @param superEventType the super event type
+     * @param typeName the name of this event type
+     */
+    public EventType(EventType<? super T> superEventType, String typeName)
+    {
+        superType = superEventType;
+        name = typeName;
+    }
+
+    /**
+     * Returns the super event type. Result is <b>null</b> for the root event
+     * type.
+     *
+     * @return the super event type
+     */
+    public EventType<? super T> getSuperType()
+    {
+        return superType;
+    }
+
+    /**
+     * Returns the name of this event type. The name has no specific semantic
+     * meaning. It is just used for debugging purposes and also part of the
+     * string representation of this event type.
+     *
+     * @return the event type name
+     */
+    public String getName()
+    {
+        return name;
+    }
+
+    /**
+     * Returns a string representation for this object. This method is mainly
+     * overridden for debugging purposes. The returned string contains the name
+     * of this event type.
+     *
+     * @return a string for this object
+     */
+    @Override
+    public String toString()
+    {
+        return String.format(FMT_TO_STRING, getClass().getSimpleName(),
+                getName());
+    }
+}

Added: commons/proper/configuration/trunk/src/test/java/org/apache/commons/configuration/event/TestEventType.java
URL: http://svn.apache.org/viewvc/commons/proper/configuration/trunk/src/test/java/org/apache/commons/configuration/event/TestEventType.java?rev=1596012&view=auto
==============================================================================
--- commons/proper/configuration/trunk/src/test/java/org/apache/commons/configuration/event/TestEventType.java (added)
+++ commons/proper/configuration/trunk/src/test/java/org/apache/commons/configuration/event/TestEventType.java Mon May 19 19:52:21 2014
@@ -0,0 +1,51 @@
+/*
+ * 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.configuration.event;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.EventObject;
+
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Test class for {@code EventType}.
+ *
+ * @version $Id$
+ */
+public class TestEventType
+{
+    /** The event type to be tested. */
+    private EventType<EventObject> eventType;
+
+    @Before
+    public void setUp() throws Exception
+    {
+        eventType = new EventType<EventObject>(null, "TEST");
+    }
+
+    /**
+     * Tests the string representation.
+     */
+    @Test
+    public void testToString()
+    {
+        String s = eventType.toString();
+        assertEquals("Wrong string", "EventType [ TEST ]", s);
+    }
+}