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/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2004 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
* ITS 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* Map.
*
* As entries are added to the map, keys are converted to all lowercase. A new
* key is compared to existing keys by comparing newKey.toString().toLower()
* to the lowercase values in the current KeySet.
*
* Null keys are supported.
*
* The keySet() method returns all lowercase keys, or nulls.
*
* Example:
*
* Map map = new CaseInsensitiveMap();
* map.put("One", "One");
* map.put("Two", "Two");
* map.put(null, "Three");
* map.put("one", "Four");
*
* creates a CaseInsensitiveMap with three entries.
* map.get(null) returns "Three" and map.get("ONE")
* returns "Four". The Set returned by keySet()
* equals {"one", "two", null}.
*
* @since Commons Collections 3.0
* @version $Revision: 1.3 $ $Date: 2004/01/14 21:43:10 $
*
* @author Commons-Collections team
*/
public class CaseInsensitiveMap extends AbstractHashedMap implements Serializable, Cloneable {
/** Serialisation version */
private static final long serialVersionUID = -7074655917369299456L;
/**
* Constructs a new empty map with default size and load factor.
*/
public CaseInsensitiveMap() {
super(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_THRESHOLD);
}
/**
* Constructs a new, empty map with the specified initial capacity.
*
* @param initialCapacity the initial capacity
* @throws IllegalArgumentException if the initial capacity is less than one
*/
public CaseInsensitiveMap(int initialCapacity) {
super(initialCapacity);
}
/**
* Constructs a new, empty map with the specified initial capacity and
* load factor.
*
* @param initialCapacity the initial capacity
* @param loadFactor the load factor
* @throws IllegalArgumentException if the initial capacity is less than one
* @throws IllegalArgumentException if the load factor is less than zero
*/
public CaseInsensitiveMap(int initialCapacity, float loadFactor) {
super(initialCapacity, loadFactor);
}
/**
* Constructor copying elements from another map.
*
* Keys will be converted to lower case strings, which may cause
* some entries to be removed (if string representation of keys differ
* only by character case).
*
* @param map the map to copy
* @throws NullPointerException if the map is null
*/
public CaseInsensitiveMap(Map map) {
super(map);
}
//-----------------------------------------------------------------------
/**
* Overrides convertKey() from {@link AbstractHashedMap} to convert keys to
* lower case.
*
* Returns null if key is null.
*
* @param key the key convert
* @return the converted key
*/
protected Object convertKey(Object key) {
if (key != null) {
return key.toString().toLowerCase();
} else {
return AbstractHashedMap.NULL;
}
}
//-----------------------------------------------------------------------
/**
* Clones the map without cloning the keys or values.
*
* @return a shallow clone
*/
public Object clone() {
return super.clone();
}
/**
* Write the map out using a custom routine.
*/
private void writeObject(ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
doWriteObject(out);
}
/**
* Read the map in using a custom routine.
*/
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
doReadObject(in);
}
}