| gvSIG desktop 1

/**

 * 

 */

package org.gvsig.i18n.utils;

import java.io.IOException;

import java.io.InputStream;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

/**

 * The DoubleProperties class represents a set of properties. It provides the

 * same functionality as its parent class, Properties. Besides that, it also

 * provides an efficient method to get the key associated with a value.  

 * 

 * @author cesar

 *

 */

public class DoubleProperties extends OrderedProperties {

        /**

         * 

         */

        private static final long serialVersionUID = -1738114064256800193L;

        HashMap reverseMap = new HashMap();

        public DoubleProperties() {

                super();

        }

        public DoubleProperties(OrderedProperties defaults) {

                super(defaults);

                Iterator keysIterator = this.keySet().iterator();

                ArrayList keySet;

                String key, value;

                while (keysIterator.hasNext()) {

                        key = (String) keysIterator.next();

                        value = this.getProperty(key);

                        if (reverseMap.containsKey(value)) {

                                keySet = (ArrayList) reverseMap.get(value);

                                keySet.add(key);

                        }

                        else {

                                keySet = new ArrayList();

                                keySet.add(key);

                                reverseMap.put(value, keySet);

                        }

                }

        }

        public void load(InputStream stream) throws IOException {

                super.load(stream);

                Iterator keysIterator = this.keySet().iterator();

                ArrayList keySet;

                String key, value;

                while (keysIterator.hasNext()) {

                        key = (String) keysIterator.next();

                        value = this.getProperty(key);

                        if (reverseMap.containsKey(value)) {

                                keySet = (ArrayList) reverseMap.get(value);

                                keySet.add(key);

                        }

                        else {

                                keySet = new ArrayList();

                                keySet.add(key);

                                reverseMap.put(value, keySet);

                        }

                }

        }

        public Object setProperty(String key, String value) {

                ArrayList keySet;

                Object returnValue = super.setProperty(key, value);

                if (reverseMap.containsKey(value)) {

                        keySet = (ArrayList) reverseMap.get(value);

                        keySet.add(key);

                }

                else {

                        keySet = new ArrayList();

                        keySet.add(key);

                        reverseMap.put(value, keySet);

                }

                return returnValue;

        }

        /**

         * Gets the key associated with the provided value. If there

         * are several associated keys, returns one of them.

         * 

         * @param value

         * @return The key associated with the provided value, or null

         * if the value is not present in the dictionary. If there

         * are several associated keys, returns one of them.

         */

        public String getAssociatedKey(String value) {

                ArrayList keySet = (ArrayList) reverseMap.get(value);

                if (keySet==null) return null;

                return (String) keySet.get(0);

        }

        /**

         * Returns the keys associated with the provided value. If there

         * are several associated keys, returns one of them.

         * 

         * @param value

         * @return An ArrayList containing the keys associated with the

         * provided value, or null if the value is not present in the 

         * dictionary.

         */

        public ArrayList getAssociatedKeys(String value) {

                return (ArrayList) reverseMap.get(value);

        }

        public Object remove(Object key) {

                Object value = super.remove(key);

                if (value==null) return null;

                ArrayList keySet = (ArrayList) reverseMap.get(value);

                if (keySet==null) return null;

                if (keySet.size()<=1) {

                        //if it's the last key associated wit the value, remove the

                        // value from the reverseDictionary                        

                        reverseMap.remove(value);

                }

                else {

                        // otherwise, remove the key from the list of associated keys

                        keySet.remove(key);

                }

                return value;

        }        

}