collectionutilities.java

来自「本程序是有IBM开发的一个基于数据表格的组件,里面有相关的例子和DOC,本站资料」· Java 代码 · 共 109 行

package com.ibm.j2x.util;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;

import org.apache.commons.collections.Bag;
import org.apache.commons.collections.SortedBag;

import com.ibm.j2x.util.collection.ObservableBag;
import com.ibm.j2x.util.collection.ObservableList;
import com.ibm.j2x.util.collection.ObservableMap;
import com.ibm.j2x.util.collection.ObservableSet;
import com.ibm.j2x.util.collection.ObservableSortedBag;
import com.ibm.j2x.util.collection.ObservableSortedMap;
import com.ibm.j2x.util.collection.ObservableSortedSet;

/**
 * The CollectionUtilities provides methods for wrapping normal Collection
 * objects with ObservableCollection objects, which allows a listener to register 
 * for changes to the Collection object.
 * <p>Although the Collection interface is not implemented by Maps, and therefore
 * it seems inconsistent to place it in a CollectionUtilities class, it is sticking
 * with the inconsistent Sun standard used in the <code>Collections</code> object.
 * @author MAbernethy
 */
public class CollectionUtilities
{
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the list by calling its <code>addCollectionListener()</code> method.
	 * @param l the list for which the observable list is returned
	 * @return an observable view of the specified list
	 */
	public static List observableList(List l)
	{
		return new ObservableList(l);
	}
	
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the set by calling its <code>addCollectionListener()</code> method.
	 * @param s the set for which the observable set is returned
	 * @return an observable view of the specified set
	 */
	public static Set observableSet(Set s)
	{
		return new ObservableSet(s);
	}
	
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the sorted set by calling its <code>addCollectionListener()</code> method.
	 * @param s the sorted set for which the observable sorted set is returned
	 * @return an observable view of the specified sorted set
	 */
	public static SortedSet observableSortedSet(SortedSet s)
	{
		return new ObservableSortedSet(s);
	}
	
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the map by calling its <code>addCollectionListener()</code> method.
	 * @param m the map for which the observable map is returned
	 * @return an observable view of the specified map
	 */	
	public static Map observableMap(Map m)
	{
		return new ObservableMap(m);
	}
	
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the sorted map by calling its <code>addCollectionListener()</code> method.
	 * @param m the sorted map for which the observable sorted map is returned
	 * @return an observable view of the specified sorted map
	 */
	public static SortedMap observableSortedMap(SortedMap m)
	{
		return new ObservableSortedMap(m);
	}
	
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the bag by calling its <code>addCollectionListener()</code> method.
	 * @param b the bag for which the observable bag is returned
	 * @return an observable view of the specified bag
	 */
	public static Bag observableBag(Bag b)
	{
		return new ObservableBag(b);
	}
	
	/**
	 * Returns an observable view of the specified object.  Listeners can observe
	 * changes to the sorted bag by calling its <code>addCollectionListener()</code> method.
	 * @param b the sorted bag for which the observable sorted bag is returned
	 * @return an observable view of the specified sorted bag
	 */
	public static SortedBag observableSortedBag(SortedBag b)
	{
		return new ObservableSortedBag(b);
	}
}