diff -r 000000000000 -r fb9019fb1bf7 src/net/fortuna/ical4j/model/IndexedComponentList.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/net/fortuna/ical4j/model/IndexedComponentList.java	Tue Feb 10 18:12:00 2015 +0100
@@ -0,0 +1,105 @@
+/**
+ * Copyright (c) 2012, Ben Fortuna
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  o Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ *  o Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ *  o Neither the name of Ben Fortuna nor the names of any other contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.fortuna.ical4j.model;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+
+/**
+ * $Id$
+ *
+ * Created on 4/02/2006
+ *
+ * Provides indexing of components on a specific property.
+ * @author Ben Fortuna
+ */
+public class IndexedComponentList {
+
+    private static final ComponentList EMPTY_LIST = new ComponentList();
+    
+    private Map index;
+    
+    /**
+     * Creates a new instance indexed on properties with the specified name.
+     * @param list a list of components
+     * @param propertyName the name of the properties to index on
+     */
+    public IndexedComponentList(final ComponentList list, final String propertyName) {
+        final Map indexedComponents = new HashMap();
+        for (final Iterator i = list.iterator(); i.hasNext();) {
+            final Component component = (Component) i.next();
+            for (final Iterator j = component.getProperties(propertyName).iterator(); j.hasNext();) {
+                final Property property = (Property) j.next();
+                ComponentList components = (ComponentList) indexedComponents.get(property.getValue());
+                if (components == null) {
+                    components = new ComponentList();
+                    indexedComponents.put(property.getValue(), components);
+                }
+                components.add(component);
+            }
+        }
+        this.index = Collections.unmodifiableMap(indexedComponents);
+    }
+    
+    /**
+     * Returns a list of components containing a property with the
+     * specified value.
+     * @param propertyValue the value of the property contained in the
+     * returned components
+     * @return a component list
+     */
+    public ComponentList getComponents(final String propertyValue) {
+        ComponentList components = (ComponentList) index.get(propertyValue);
+        if (components == null) {
+            components = EMPTY_LIST;
+        }
+        return components;
+    }
+    
+    /**
+     * Returns the first component containing a property with the specified
+     * value.
+     * @param propertyValue the value of the property identified in the returned
+     * component
+     * @return a component or null if no component is found containing a property
+     * with the specified value
+     */
+    public Component getComponent(final String propertyValue) {
+        final ComponentList components = getComponents(propertyValue);
+        if (!components.isEmpty()) {
+            return (Component) components.iterator().next();
+        }
+        return null;
+    }
+}