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    /*
 * Copyright 2002-2016 Jalal Kiswani.
 *
 * Licensed 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 com.jk.util;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Map.Entry;

/**
 * The Class JKCollectionUtil.
 *
 * @author Jalal Kiswani
 */
public class JKCollectionUtil {

	/**
	 * Fix properties keys.
	 *
	 * @param prop
	 *            the prop
	 */
	public static void fixPropertiesKeys(final Properties prop) {
		final Enumeration keys = prop.keys();
		while (keys.hasMoreElements()) {
			final String currentKey = (String) keys.nextElement();
			final String fixedKey = fixPropertyKey(currentKey);
			final String value = prop.getProperty(currentKey);
			prop.remove(currentKey);
			prop.setProperty(fixedKey, value);
		}
	}

	/**
	 * Fix property key.
	 *
	 * @param name
	 *            the name
	 * @return the string
	 */
	public static String fixPropertyKey(final String name) {
		return name.toLowerCase().replace("_", "-");
	}

	/**
	 * Gat random item.
	 *
	 * @param items
	 *            the items
	 * @return the object
	 */
	// //////////////////////////////////////////////////////////
	public static Object gatRandomItem(final List items) {
		if (items == null || items.size() == 0) {
			return null;
		}
		final int itemIndex = (int) (Math.random() * items.size());
		return items.get(itemIndex);
	}

	/**
	 * Unify the objects in the list according to the hash code IMPORTANT :
	 * hashcode usage here is different from the Java Spec , IT SHOULD BE
	 * UNIUQUE FOR EACH OBJECT WHICH SHOULD HOLD SOMTHING LIKE THE DATABASE
	 * PRIMARY KEY.
	 *
	 * @param hash
	 *            the hash
	 * @param list
	 *            the list
	 */
	public static void unifyReferences(final Hashtable hash, final List list) {
		if (list != null) {
			for (int i = 0; i < list.size(); i++) {
				final Object itemAtList = list.get(i);
				final Object unifiedReferences = unifyReferences(hash, itemAtList);
				list.set(i, unifiedReferences);
			}
		}
	}

	// //////////////////////////////////////////////////////////
	/**
	 * return unified reference.
	 *
	 * @param hash
	 *            the hash
	 * @param object
	 *            the object
	 * @return the object
	 */
	public static Object unifyReferences(final Hashtable hash, Object object) {
		final Object itemAtHash = hash.get(object.hashCode());
		if (itemAtHash == null) {
			hash.put(object.hashCode(), object);
		} else {
			object = itemAtHash;
		}
		return object;
	}

	/**
	 * To string.
	 *
	 * @param list
	 *            the list
	 * @return the string
	 */
	public static String toString(final List list) {
		final StringBuffer buf = new StringBuffer("[");
		int i = 0;
		for (final Object object : list) {
			if (i++ > 0) {
				buf.append(",");
			}
			buf.append(object == null ? "null" : JKObjectUtil.toString(object,true));
		}
		buf.append("]");
		return buf.toString();
	}

	/**
	 * To string.
	 *
	 * @param properties
	 *            the properties
	 * @return the string
	 */
	public static String toString(final Properties properties) {
		final Properties newProperties = new Properties();
		final Enumeration keys = properties.keys();
		while (keys.hasMoreElements()) {
			final String key = keys.nextElement().toString();
			if (key.toLowerCase().contains("password")) {
				continue;
			}
			newProperties.setProperty(key, properties.getProperty(key));
		}
		return newProperties.toString();
	}

	/**
	 * Sort hash table.
	 *
	 * @param hash
	 *            the hash
	 * @param asc
	 *            the asc
	 * @return the array list
	 */
	public static List sortHashTable(final Hashtable hash, final boolean asc) {
		// Put keys and values in to an arraylist using entryset
		final ArrayList myArrayList = new ArrayList(hash.entrySet());
		// Sort the values based on values first and then keys.
		Collections.sort(myArrayList, new HashComparator(asc));
		return myArrayList;
	}

	static class HashComparator implements Comparator {
		private final boolean asc;

		public HashComparator(final boolean asc) {
			this.asc = asc;
		}

		@Override
		public int compare(final Object obj1, final Object obj2) {
			int result = 0;
			final Map.Entry e1 = (Map.Entry) obj1;
			final Map.Entry e2 = (Map.Entry) obj2;// Sort based on values.
			final Comparable> value1 = (Comparable>) e1.getValue();
			final Comparable value2 = (Comparable) e2.getValue();
			if (value1.compareTo(value2) == 0) {
				final Comparable> key1 = (Comparable>) e1.getKey();
				final Comparable key2 = (Comparable) e2.getKey();
				// Sort String in an alphabetical order
				result = key1.compareTo(key2);
			} else {
				if (this.asc) {
					result = value1.compareTo(value2);
				} else {
					result = value2.compareTo(value1);
				}
			}
			return result;
		}
	}

}
    
    
    
    

    




    
    
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