/*
* 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.Store{
/// <summary> A memory-resident {@link IndexOutput} implementation.
///
/// </summary>
/// <version> $Id: RAMOutputStream.java 150537 2004-09-28 20:45:26Z cutting $
/// </version>
public class RAMOutputStream : BufferedIndexOutput
{
private RAMFile file;
private int pointer = 0;
/// <summary>Construct an empty output buffer. </summary>
public RAMOutputStream() : this(new RAMFile())
{
}
internal RAMOutputStream(RAMFile f)
{
file = f;
}
/// <summary>Copy the current contents of this buffer to the named output. </summary>
public virtual void WriteTo(IndexOutput out_Renamed)
{
Flush();
long end = file.length;
long pos = 0;
int buffer = 0;
while (pos < end)
{
int length = BUFFER_SIZE;
long nextPos = pos + length;
if (nextPos > end)
{
// at the last buffer
length = (int) (end - pos);
}
out_Renamed.WriteBytes((byte[]) file.buffers[buffer++], length);
pos = nextPos;
}
}
/// <summary>Resets this to an empty buffer. </summary>
public virtual void Reset()
{
try
{
Seek(0);
}
catch (System.IO.IOException e)
{
// should never happen
throw new System.SystemException(e.ToString());
}
file.length = 0;
}
public override void FlushBuffer(byte[] src, int len)
{
int bufferNumber = pointer / BUFFER_SIZE;
int bufferOffset = pointer % BUFFER_SIZE;
int bytesInBuffer = BUFFER_SIZE - bufferOffset;
int bytesToCopy = bytesInBuffer >= len?len:bytesInBuffer;
if (bufferNumber == file.buffers.Count)
file.buffers.Add(new byte[BUFFER_SIZE]);
byte[] buffer = (byte[]) file.buffers[bufferNumber];
Array.Copy(src, 0, buffer, bufferOffset, bytesToCopy);
if (bytesToCopy < len)
{
// not all in one buffer
int srcOffset = bytesToCopy;
bytesToCopy = len - bytesToCopy; // remaining bytes
bufferNumber++;
if (bufferNumber == file.buffers.Count)
file.buffers.Add(new byte[BUFFER_SIZE]);
buffer = (byte[]) file.buffers[bufferNumber];
Array.Copy(src, srcOffset, buffer, 0, bytesToCopy);
}
pointer += len;
if (pointer > file.length)
file.length = pointer;
file.lastModified = System.DateTime.Now.Ticks;
}
public override void Close()
{
base.Close();
}
public override void Seek(long pos)
{
base.Seek(pos);
pointer = (int) pos;
}
public override long Length()
{
return file.length;
}
}
}
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