#region License
/*
* Copyright 2002-2007 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;
using System.IO;
using Spring.Core.IO;
using Spring.Util;
namespace Spring.Objects.Factory.Config{
/// <summary>
/// Implementation of <see cref="IVariableSource"/> that
/// resolves variable name against Java-style property file.
/// </summary>
/// <seealso cref="Properties"/>
/// <author>Aleksandar Seovic</author>
[Serializable]
public class PropertyFileVariableSource : IVariableSource
{
private IResource[] locations;
private Properties properties;
/// <summary>
/// Gets or sets the locations of the property files
/// to read properties from.
/// </summary>
/// <value>
/// The locations of the property files
/// to read properties from.
/// </value>
public IResource[] Locations
{
get { return locations; }
set { locations = value; }
}
/// <summary>
/// Convinience property. Gets or sets a single location
/// to read properties from.
/// </summary>
/// <value>
/// A location to read properties from.
/// </value>
public IResource Location
{
set { locations = new IResource[] { value} ;}
}
/// <summary>
/// Before requesting a variable resolution, a client should
/// ask, whether the source can resolve a particular variable name.
/// </summary>
/// <param name="name">the name of the variable to resolve</param>
/// <returns><c>true</c> if the variable can be resolved, <c>false</c> otherwise</returns>
public bool CanResolveVariable(string name)
{
if (properties == null)
{
InitProperties();
}
return properties.Contains(name);
}
/// <summary>
/// Resolves variable value for the specified variable name.
/// </summary>
/// <param name="name">
/// The name of the variable to resolve.
/// </param>
/// <returns>
/// The variable value if able to resolve, <c>null</c> otherwise.
/// </returns>
public string ResolveVariable(string name)
{
if (properties == null)
{
InitProperties();
}
return properties.GetProperty(name);
}
/// <summary>
/// Initializes properties based on the specified
/// property file locations.
/// </summary>
private void InitProperties()
{
properties = new Properties();
foreach (IResource location in locations)
{
using (Stream input = location.InputStream)
{
properties.Load(input);
}
}
}
}
}
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