#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.IO;
using Spring.Util;
#endregion
namespace Spring.Core.IO{
/// <summary>
/// <see cref="IResource"/> adapter implementation for a
/// <see cref="System.IO.Stream"/>.
/// </summary>
/// <remarks>
/// <p>
/// Should only be used if no other <see cref="Spring.Core.IO.IResource"/>
/// implementation is applicable.
/// </p>
/// <p>
/// In contrast to other <see cref="Spring.Core.IO.IResource"/>
/// implementations, this is an adapter for an <i>already opened</i>
/// resource - the <see cref="Spring.Core.IO.InputStreamResource.IsOpen"/>
/// therefore always returns <see langword="true"/>. Do not use this class
/// if you need to keep the resource descriptor somewhere, or if you need
/// to read a stream multiple times.
/// </p>
/// </remarks>
/// <author>Juergen Hoeller</author>
/// <author>Rick Evans (.NET)</author>
public class InputStreamResource : AbstractResource
{
#region Constructor (s) / Destructor
/// <summary>
/// Creates a new instance of the
/// <see cref="Spring.Core.IO.InputStreamResource"/> class.
/// </summary>
/// <param name="inputStream">
/// The input <see cref="System.IO.Stream"/> to use.
/// </param>
/// <param name="description">
/// Where the input <see cref="System.IO.Stream"/> comes from.
/// </param>
/// <exception cref="System.ArgumentNullException">
/// If the supplied <paramref name="inputStream"/> is
/// <see langword="null"/>.
/// </exception>
public InputStreamResource(Stream inputStream, string description)
{
AssertUtils.ArgumentNotNull(inputStream, "inputStream");
_inputStream = inputStream;
_description = description == null ? string.Empty : description;
}
#endregion
#region Properties
/// <summary>
/// The input <see cref="System.IO.Stream"/> to use.
/// </summary>
/// <exception cref="System.InvalidOperationException">
/// If the underlying <see cref="System.IO.Stream"/> has already
/// been read.
/// </exception>
public override Stream InputStream
{
get
{
if (_inputStream == null)
{
throw new InvalidOperationException(
"InputStream has already been read - " +
"do not use InputStreamResource if a stream " +
"needs to be read multiple times");
}
Stream result = _inputStream;
_inputStream = null;
return result;
}
}
/// <summary>
/// Returns a description for this resource.
/// </summary>
/// <value>
/// A description for this resource.
/// </value>
/// <seealso cref="Spring.Core.IO.IResource.Description"/>
public override string Description
{
get { return _description; }
}
/// <summary>
/// This implementation always returns true
/// </summary>
public override bool IsOpen
{
get { return true; }
}
/// <summary>
/// This implemementation always returns true
/// </summary>
public override bool Exists
{
get { return true; }
}
#endregion
#region Fields
private Stream _inputStream;
private string _description;
#endregion
}
}
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