#region License
/*
* Copyright 2002-2005 the original author or authors.
*
* 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.
*/
#endregion
#if NET_2_0
#region Imports
using System;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
#endregion
namespace Spring.Util.Generic{
/// <summary>
/// Miscellaneous generic collection utility methods.
/// </summary>
/// <remarks>
/// Mainly for internal use within the framework.
/// </remarks>
/// <author>Mark Pollack (.NET)</author>
public sealed class CollectionUtils
{
#region Methods
/// <summary>
/// Determine whether a given collection only contains
/// a single unique object
/// </summary>
/// <param name="coll"></param>
/// <returns></returns>
public static bool HasUniqueObject<T>(ICollection<T> coll)
{
if (coll.Count == 0)
{
return false;
}
object candidate = null;
foreach (object elem in coll)
{
if (candidate == null)
{
candidate = elem;
}
else if (candidate != elem)
{
return false;
}
}
return true;
}
/// <summary>
/// Determines whether the <paramref name="collection"/> contains the specified <paramref name="element"/>.
/// </summary>
/// <param name="collection">The collection to check.</param>
/// <param name="element">The object to locate in the collection.</param>
/// <returns><see lang="true"/> if the element is in the collection, <see lang="false"/> otherwise.</returns>
public static bool Contains<T>(ICollection<T> collection, Object element)
{
if (collection == null)
{
throw new ArgumentNullException("Collection cannot be null.");
}
MethodInfo method;
method = collection.GetType().GetMethod("contains", BindingFlags.IgnoreCase | BindingFlags.Instance | BindingFlags.Static | BindingFlags.Public);
if (null == method)
{
throw new InvalidOperationException("Collection type " + collection.GetType() + " does not implement a Contains() method.");
}
return (bool) method.Invoke(collection, new Object[] {element});
}
/// <summary>
/// Determines whether the collection contains all the elements in the specified collection.
/// </summary>
/// <param name="targetCollection">The collection to check.</param>
/// <param name="sourceCollection">Collection whose elements would be checked for containment.</param>
/// <returns>true if the target collection contains all the elements of the specified collection.</returns>
public static bool ContainsAll<T>(ICollection<T> targetCollection, ICollection<T> sourceCollection)
{
if (targetCollection == null || sourceCollection == null)
{
throw new ArgumentNullException("Collection cannot be null.");
}
if ( sourceCollection.Count == 0 && targetCollection.Count > 1 )
return true;
IEnumerator sourceCollectionEnumerator = sourceCollection.GetEnumerator();
bool contains = false;
MethodInfo method;
method = targetCollection.GetType().GetMethod("containsAll", BindingFlags.IgnoreCase | BindingFlags.Instance | BindingFlags.Static | BindingFlags.Public);
if (method != null)
contains = (bool) method.Invoke(targetCollection, new Object[] {sourceCollection});
else
{
method = targetCollection.GetType().GetMethod("Contains", BindingFlags.IgnoreCase | BindingFlags.Instance | BindingFlags.Static | BindingFlags.Public);
if (method == null)
{
throw new InvalidOperationException("Target collection does not implment a Contains() or ContainsAll() method.");
}
while (sourceCollectionEnumerator.MoveNext())
{
if ((contains = (bool) method.Invoke(targetCollection, new Object[] {sourceCollectionEnumerator.Current})) == false)
break;
}
}
return contains;
}
/// <summary>
/// Removes all the elements from the target collection that are contained in the source collection.
/// </summary>
/// <param name="targetCollection">Collection where the elements will be removed.</param>
/// <param name="sourceCollection">Elements to remove from the target collection.</param>
public static void RemoveAll<T>(ICollection<T> targetCollection, ICollection<T> sourceCollection)
{
if (targetCollection == null)
{
throw new ArgumentNullException("targetCollection", "Collection cannot be null.");
}
if (sourceCollection == null)
{
throw new ArgumentNullException("sourceCollection", "Collection cannot be null.");
}
foreach (T element in sourceCollection)
{
if (targetCollection.Contains(element))
{
targetCollection.Remove(element);
}
}
}
#endregion
}
}
#endif
|