hashmapsorter.java

esri的ArcGIS Server超级学习模板程序（for java）

package com.esri.solutions.jitk.web.tasks.query.querybuilder;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;

public class HashMapSorter {
	@SuppressWarnings("unchecked")
	public LinkedHashMap sort(HashMap passedMap, boolean ascending) {
		// no strong type defined for the sorting list, Collections.sort() won't take it.
		// this is legacy code refactored into a separate class. 
		List mapKeys = new ArrayList(passedMap.keySet());
		List mapValues = new ArrayList(passedMap.values());
		Collections.sort(mapValues);
		Collections.sort(mapKeys);

		if (!ascending) Collections.reverse(mapValues);
		LinkedHashMap<Object, Object> someMap = new LinkedHashMap();
		Iterator valueIt = mapValues.iterator();
		
		while (valueIt.hasNext()){
			Object val = valueIt.next();
			Iterator keyIt = mapKeys.iterator();
			
			while (keyIt.hasNext()){
				Object key = keyIt.next();
				
				if (passedMap.get(key).toString().equals(val.toString())){
					passedMap.remove(key);
					mapKeys.remove(key);
					someMap.put(key, val);
					break;
				}
			}
		}
		
		return someMap;		
	}
}