/*
* Copyright 2004 The Apache Software Foundation
*
* 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.
*/
using System;
namespace Lucene.Net.Util{
/// <summary> A serializable Enum class.</summary>
[Serializable]
public abstract class Parameter
{
internal static System.Collections.IDictionary allParameters = new System.Collections.Hashtable();
private System.String name;
private Parameter()
{
// typesafe enum pattern, no public constructor
}
protected internal Parameter(System.String name)
{
// typesafe enum pattern, no public constructor
this.name = name;
System.String key = MakeKey(name);
if (allParameters.Contains(key))
throw new System.ArgumentException("Parameter name " + key + " already used!");
allParameters[key] = this;
}
private System.String MakeKey(System.String name)
{
return GetType() + " " + name;
}
public override System.String ToString()
{
return name;
}
/// <summary> Resolves the deserialized instance to the local reference for accurate
/// equals() and == comparisons.
///
/// </summary>
/// <returns> a reference to Parameter as resolved in the local VM
/// </returns>
/// <throws> ObjectStreamException </throws>
protected internal virtual System.Object ReadResolve()
{
System.Object par = allParameters[MakeKey(name)];
if (par == null)
throw new System.IO.IOException("Unknown parameter value: " + name);
return par;
}
}
}
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