/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2000-2010 Oracle. All rights reserved.
*
*/
package com.sleepycat.bind.serial;
import com.sleepycat.util.FastOutputStream;
/**
* A base class for serial bindings creators that provides control over the
* allocation of the output buffer.
*
* <p>Serial bindings append data to a {@link FastOutputStream} instance. This
* object has a byte array buffer that is resized when it is full. The
* reallocation of this buffer can be a performance factor for some
* applications using large objects. To manage this issue, the {@link
* #setSerialBufferSize} method may be used to control the initial size of the
* buffer, and the {@link #getSerialOutput} method may be overridden by
* subclasses to take over creation of the FastOutputStream object.</p>
*
* @see <a href="SerialBinding.html#evolution">Class Evolution</a>
*
* @author Mark Hayes
*/
public class SerialBase {
private int outputBufferSize;
/**
* Initializes the initial output buffer size to zero.
*
* <p>Unless {@link #setSerialBufferSize} is called, the default {@link
* FastOutputStream#DEFAULT_INIT_SIZE} size will be used.</p>
*/
public SerialBase() {
outputBufferSize = 0;
}
/**
* Sets the initial byte size of the output buffer that is allocated by the
* default implementation of {@link #getSerialOutput}.
*
* <p>If this property is zero (the default), the default {@link
* FastOutputStream#DEFAULT_INIT_SIZE} size is used.</p>
*
* @param byteSize the initial byte size of the output buffer, or zero to
* use the default size.
*/
public void setSerialBufferSize(int byteSize) {
outputBufferSize = byteSize;
}
/**
* Returns the initial byte size of the output buffer.
*
* @return the initial byte size of the output buffer.
*
* @see #setSerialBufferSize
*/
public int getSerialBufferSize() {
return outputBufferSize;
}
/**
* Returns an empty SerialOutput instance that will be used by the serial
* binding or key creator.
*
* <p>The default implementation of this method creates a new SerialOutput
* with an initial buffer size that can be changed using the {@link
* #setSerialBufferSize} method.</p>
*
* <p>This method may be overridden to return a FastOutputStream instance.
* For example, an instance per thread could be created and returned by
* this method. If a FastOutputStream instance is reused, be sure to call
* its {@link FastOutputStream#reset} method before each use.</p>
*
* @param object is the object to be written to the serial output, and may
* be used by subclasses to determine the size of the output buffer.
*
* @return an empty FastOutputStream instance.
*
* @see #setSerialBufferSize
*/
protected FastOutputStream getSerialOutput(Object object) {
int byteSize = getSerialBufferSize();
if (byteSize != 0) {
return new FastOutputStream(byteSize);
} else {
return new FastOutputStream();
}
}
}