KeyValueMap.java

/*
 * 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.sling.provisioning.model;

import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.TreeMap;

/**
 * Helper class to hold key value pairs.
 */
public class KeyValueMap<T>
    extends Commentable
    implements Iterable<Map.Entry<String, T>> {

    /** The map holding the actual key value pairs. */
    private final Map<String, T> properties = new TreeMap<String, T>();

    /**
     * Get an item from the map.
     * @param key The key of the item.
     * @return The item or {@code null}.
     */
    public T get(final String key) {
        return this.properties.get(key);
    }

    /**
     * Put an item in the map
     * @param key The key of the item.
     * @param value The value
     */
    public void put(final String key, final T value) {
        this.properties.put(key, value);
    }

    /**
     * Remove an item from the map
     * @param key The key of the item.
     * @return The previously stored value for the key or {@code null}.
     * @since 1.1
     */
    public T remove(final String key) {
        return this.properties.remove(key);
    }

    /**
     * Put all items from the other map in this map
     * @param map The other map
     */
    public void putAll(final KeyValueMap<T> map) {
        this.properties.putAll(map.properties);
    }

    @Override
    public Iterator<Entry<String, T>> iterator() {
        return this.properties.entrySet().iterator();
    }

    /**
     * Check whether this map is empty.
     * @return {@code true} if the map is empty.
     */
    public boolean isEmpty() {
        return this.properties.isEmpty();
    }

    @Override
    public String toString() {
        return properties.toString();
    }

    /**
     * Get the size of the map.
     * @return The size of the map.
     * @since 1.1
     */
    public int size() {
        return this.properties.size();
    }

    /**
     * Clear the map
     * @since 1.7
     */
    public void clear() {
        this.properties.clear();
    }
}