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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.collections.map;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;

import org.apache.commons.collections.BoundedMap;
import org.apache.commons.collections.collection.UnmodifiableCollection;
import org.apache.commons.collections.set.UnmodifiableSet;

Decorates another SortedMap to fix the size blocking add/remove.

Any action that would change the size of the map is disallowed.
The put method is allowed to change the value associated with an existing
key however.

If trying to remove or clear the map, an UnsupportedOperationException is
thrown. If trying to put a new mapping into the map, an 
IllegalArgumentException is thrown. This is because the put method can 
succeed if the mapping's key already exists in the map, so the put method
is not always unsupported.

Note that FixedSizeSortedMap is not synchronized and is not thread-safe. If you wish to use this map from multiple threads concurrently, you must use appropriate synchronization. The simplest approach is to wrap this map using Collections.synchronizedSortedMap. This class may throw exceptions when accessed by concurrent threads without synchronization. 

This class is Serializable from Commons Collections 3.1.
Author:
Stephen Colebourne, Paul Jack
Since:
Commons Collections 3.0
Version:
$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $/**
 * Decorates another <code>SortedMap</code> to fix the size blocking add/remove.
 * <p>
 * Any action that would change the size of the map is disallowed.
 * The put method is allowed to change the value associated with an existing
 * key however.
 * <p>
 * If trying to remove or clear the map, an UnsupportedOperationException is
 * thrown. If trying to put a new mapping into the map, an 
 * IllegalArgumentException is thrown. This is because the put method can 
 * succeed if the mapping's key already exists in the map, so the put method
 * is not always unsupported.
 * <p>
 * <strong>Note that FixedSizeSortedMap is not synchronized and is not thread-safe.</strong>
 * If you wish to use this map from multiple threads concurrently, you must use
 * appropriate synchronization. The simplest approach is to wrap this map
 * using {@link java.util.Collections#synchronizedSortedMap}. This class may throw 
 * exceptions when accessed by concurrent threads without synchronization.
 * <p>
 * This class is Serializable from Commons Collections 3.1.
 *
 * @since Commons Collections 3.0
 * @version $Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
 * 
 * @author Stephen Colebourne
 * @author Paul Jack
 */
public class FixedSizeSortedMap
        extends AbstractSortedMapDecorator
        implements SortedMap, BoundedMap, Serializable {

    
Serialization version /** Serialization version */
    private static final long serialVersionUID = 3126019624511683653L;

    
Factory method to create a fixed size sorted map.
Params:
map –  the map to decorate, must not be null
Throws:
IllegalArgumentException – if map is null/**
     * Factory method to create a fixed size sorted map.
     * 
     * @param map  the map to decorate, must not be null
     * @throws IllegalArgumentException if map is null
     */
    public static SortedMap decorate(SortedMap map) {
        return new FixedSizeSortedMap(map);
    }

    //-----------------------------------------------------------------------
    
Constructor that wraps (not copies).
Params:
map –  the map to decorate, must not be null
Throws:
IllegalArgumentException – if map is null/**
     * Constructor that wraps (not copies).
     * 
     * @param map  the map to decorate, must not be null
     * @throws IllegalArgumentException if map is null
     */
    protected FixedSizeSortedMap(SortedMap map) {
        super(map);
    }

    
Gets the map being decorated.
Returns:
the decorated map/**
     * Gets the map being decorated.
     * 
     * @return the decorated map
     */
    protected SortedMap getSortedMap() {
        return (SortedMap) map;
    }

    //-----------------------------------------------------------------------
    
Write the map out using a custom routine.
/**
     * Write the map out using a custom routine.
     */
    private void writeObject(ObjectOutputStream out) throws IOException {
        out.defaultWriteObject();
        out.writeObject(map);
    }

    
Read the map in using a custom routine.
/**
     * Read the map in using a custom routine.
     */
    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
        in.defaultReadObject();
        map = (Map) in.readObject();
    }

    //-----------------------------------------------------------------------
    public Object put(Object key, Object value) {
        if (map.containsKey(key) == false) {
            throw new IllegalArgumentException("Cannot put new key/value pair - Map is fixed size");
        }
        return map.put(key, value);
    }

    public void putAll(Map mapToCopy) {
        for (Iterator it = mapToCopy.keySet().iterator(); it.hasNext(); ) {
            if (mapToCopy.containsKey(it.next()) == false) {
                throw new IllegalArgumentException("Cannot put new key/value pair - Map is fixed size");
            }
        }
        map.putAll(mapToCopy);
    }

    public void clear() {
        throw new UnsupportedOperationException("Map is fixed size");
    }

    public Object remove(Object key) {
        throw new UnsupportedOperationException("Map is fixed size");
    }

    public Set entrySet() {
        Set set = map.entrySet();
        return UnmodifiableSet.decorate(set);
    }

    public Set keySet() {
        Set set = map.keySet();
        return UnmodifiableSet.decorate(set);
    }

    public Collection values() {
        Collection coll = map.values();
        return UnmodifiableCollection.decorate(coll);
    }

    //-----------------------------------------------------------------------
    public SortedMap subMap(Object fromKey, Object toKey) {
        SortedMap map = getSortedMap().subMap(fromKey, toKey);
        return new FixedSizeSortedMap(map);
    }

    public SortedMap headMap(Object toKey) {
        SortedMap map = getSortedMap().headMap(toKey);
        return new FixedSizeSortedMap(map);
    }

    public SortedMap tailMap(Object fromKey) {
        SortedMap map = getSortedMap().tailMap(fromKey);
        return new FixedSizeSortedMap(map);
    }

    public boolean isFull() {
        return true;
    }

    public int maxSize() {
        return size();
    }

}