MapUtil.java

/*
 * Copyright © 2014 YAOCHEN Corporation, All Rights Reserved
 */
package com.easyooo.framework.common.util;

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

/**
 * 
 * @author Killer
 */
public class MapUtil {
	
	// desc
	private static final String MAP_CLASS_KEY = "class";
	
	
	/**
	 * 比较要修改的map如果
	 * @param source
	 * @param mod
	 * @return
	 */
	@SuppressWarnings({ "unchecked", "rawtypes" })
	public static Map<String, Object> overrideExcludeNull(
			Map<String, Object> source, Map<String, Object> mod) {
		if(source == null || mod == null){
			return null;
		}
		clearNullEntry(mod);
		
		Map<String,Object> target = new HashMap(source);
		target.putAll(mod);
		return target;
	}
	
	/**
	 * Remove the class from the hashmap entry
	 * @param map
	 * @return
	 */
	public static <K,V> V clearClassEntry(Map<K,V> map){
		if (map == null) {
			return null;
		}
		return map.remove(MAP_CLASS_KEY);
	}
	
	/**
	 * remove entry when the value eq null
	 * @param map
	 */
	public static <K,V> void clearNullEntry(Map<K, V> map) {
		if (map == null) {
			return;
		}
		for (Iterator<Entry<K,V>> ite = map.entrySet().iterator(); ite
				.hasNext();) {
			if(ite.next().getValue() == null){
				ite.remove();
			}
		}
	}
	
	@SuppressWarnings("unchecked")
	public static Map<String, Object> gmap(Object...args){
		if(args.length == 1 && args[0] instanceof Map){
			return (Map<String, Object>)args[0];
		}
		
		if(args.length % 2 != 0){
			throw new IllegalArgumentException("Number of parameters is not correct");
		}
		
		Map<String, Object> targetMap = new HashMap<String, Object>();
		for (int i = 0 ; i < args.length ; i++) {
			targetMap.put(args[i].toString(), args[++i]);
		}
		
		return targetMap;
	}
}