#region License
/*
* Copyright 2002-2009 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
using System;
using System.Collections.Specialized;
namespace Spring.Objects.Factory.Config{
/// <summary>
/// Tag class which represent a Spring-managed <see cref="NameValueCollection"/> instance that
/// supports merging of parent/child definitions.
/// </summary>
public class ManagedNameValueCollection: NameValueCollection, IMergable
{
private bool mergeEnabled;
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Collections.Specialized.NameValueCollection"/> class that is empty, has the default initial capacity and uses the default case-insensitive hash code provider and the default case-insensitive comparer.
/// </summary>
public ManagedNameValueCollection()
{
}
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Collections.Specialized.NameValueCollection"/> class that is empty, has the specified initial capacity and uses the default case-insensitive hash code provider and the default case-insensitive comparer.
/// </summary>
/// <param name="capacity">The initial number of entries that the <see cref="T:System.Collections.Specialized.NameValueCollection"/> can contain.</param><exception cref="T:System.ArgumentOutOfRangeException"><paramref name="capacity"/> is less than zero.</exception>
public ManagedNameValueCollection(int capacity) : base(capacity)
{
}
/// <summary>
/// Gets a value indicating whether this instance is merge enabled for this instance
/// </summary>
/// <value>
/// <c>true</c> if this instance is merge enabled; otherwise, <c>false</c>.
/// </value>
public bool MergeEnabled
{
get { return this.mergeEnabled; }
set { this.mergeEnabled = value; }
}
/// <summary>
/// Merges the current value set with that of the supplied object.
/// </summary>
/// <remarks>The supplied object is considered the parent, and values in the
/// callee's value set must override those of the supplied object.
/// </remarks>
/// <param name="parent">The parent object to merge with</param>
/// <returns>The result of the merge operation</returns>
/// <exception cref="ArgumentNullException">If the supplied parent is <code>null</code></exception>
/// <exception cref="InvalidOperationException">If merging is not enabled for this instance,
/// (i.e. <code>MergeEnabled</code> equals <code>false</code>.</exception>
public object Merge(object parent)
{
if (!this.mergeEnabled)
{
throw new InvalidOperationException(
"Not allowed to merge when the 'MergeEnabled' property is set to 'false'");
}
if (parent == null)
{
return this;
}
NameValueCollection pDict = parent as NameValueCollection;
if (pDict == null)
{
throw new InvalidOperationException("Cannot merge with object of type [" + parent.GetType() + "]");
}
NameValueCollection merged = new ManagedNameValueCollection();
foreach (string s in pDict.AllKeys)
{
merged[s] = pDict.Get(s);
}
foreach (string s in this.AllKeys)
{
merged[s] = this.Get(s);
}
return merged;
}
}
}
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