#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
#region Imports
using System;
using System.Collections;
using System.Reflection;
#endregion
namespace Spring.Util
{
///
/// Miscellaneous collection utility methods.
///
///
/// Mainly for internal use within the framework.
///
/// Mark Pollack (.NET)
public sealed class CollectionUtils
{
///
/// Returns the first element contained in both,
///
/// The implementation assumes that
/// the source enumerable. may be null
/// the list of candidates to match against null
/// the first element found in both enumerables or null
public static object FindFirstMatch(IEnumerable source, IEnumerable candidates)
{
if (IsEmpty(source) || IsEmpty(candidates))
{
return null;
}
IList candidateList = candidates as IList;
if (candidateList == null)
{
if (candidates is ICollection)
{
candidateList = new ArrayList((ICollection)candidates);
}
else
{
candidateList = new ArrayList();
foreach (object el in candidates)
{
candidateList.Add(el);
}
}
}
foreach (object sourceElement in source)
{
if (candidateList.Contains(sourceElement))
{
return sourceElement;
}
}
return null;
}
///
/// Determines whether the specified collection is null or empty.
///
/// The collection to check.
///
/// true if the specified collection is empty or null; otherwise, false .
///
public static bool IsEmpty(IEnumerable enumerable)
{
if (enumerable == null)
return true;
if (enumerable is ICollection)
{
return (0 == ((ICollection)enumerable).Count);
}
IEnumerator it = enumerable.GetEnumerator();
if (!it.MoveNext())
{
return true;
}
return false;
}
///
/// Determines whether the specified collection is null or empty.
///
/// The collection to check.
///
/// true if the specified collection is empty or null; otherwise, false .
///
public static bool IsEmpty(ICollection collection)
{
return (collection == null || collection.Count == 0);
}
///
/// Determines whether the specified dictionary is null empty.
///
/// The dictionary to check.
///
/// true if the specified dictionary is empty or null; otherwise, false .
///
public static bool IsEmpty(IDictionary dictionary)
{
return (dictionary == null || dictionary.Count == 0);
}
}
}