Package org.bedework.util.servlet.io

Class PooledBufferedOutputStream

java.lang.Object

java.io.OutputStream

org.bedework.util.servlet.io.PooledBufferedOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class PooledBufferedOutputStream
extends OutputStream

See if we can't manage buffers better than the standard java classes - at least for the specific use we have. We are generating a lot of output and causing a lot of expansion and copying.

This may result in a lot of JVM churn. See if a pool of buffers can improve matters.

Author:

Mike Douglass

Field Summary

Fields

Modifier and Type	Field	Description
protected int	count	The number of valid bytes in the virtual buffer.

Constructor Summary

Constructors

Constructor	Description
PooledBufferedOutputStream()	Creates a new pooled buffered output stream.

Method Summary

Modifier and Type	Method	Description
void	close()	Closing can have no effect as we need to access the buffers afterwards.
InputStream	getInputStream()	Get an InputStream for the bytes in the buffer.
void	release()	This really release buffers back to the pool.
int	size()	Returns the current size of the buffer.
byte[]	toByteArray()	Creates a newly allocated byte array.
String	toString()	Converts the buffer's contents into a string decoding bytes using the platform's default character set.
String	toString(String charsetName)	Converts the buffer's contents into a string by decoding the bytes using the specified charsetName.
void	write(byte[] b, int off, int len)
void	write(int b)	Writes the specified byte to this byte array output stream.
void	writeTo(OutputStream out)	Writes the complete contents of this byte array output stream to the specified output stream argument, as if by calling the output stream's write method using out.write(buf, 0, count).

Methods inherited from class java.io.OutputStream

flush, nullOutputStream, write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

count

protected int count

The number of valid bytes in the virtual buffer.

Constructor Detail

PooledBufferedOutputStream

public PooledBufferedOutputStream()

Creates a new pooled buffered output stream.

Method Detail

write

public void write(int b)

Writes the specified byte to this byte array output stream.

Specified by:

write in class OutputStream

Parameters:

b - the byte to be written.

write

public void write(byte[] b,
                  int off,
                  int len)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

writeTo

public void writeTo(OutputStream out)
             throws IOException

Writes the complete contents of this byte array output stream to the specified output stream argument, as if by calling the output stream's write method using out.write(buf, 0, count).

Parameters:

out - the output stream to which to write the data.

Throws:

IOException - if an I/O error occurs.

getInputStream

public InputStream getInputStream()
                           throws IOException

Get an InputStream for the bytes in the buffer. No guarantees if writes take place after this is called.

Returns:

InputStream

Throws:

IOException

toByteArray

public byte[] toByteArray()

Creates a newly allocated byte array. Its size is the current size of this output stream and the valid contents of the buffer have been copied into it.

Returns:

the current contents of this output stream, as a byte array.

See Also:

ByteArrayOutputStream.size()

size

public int size()

Returns the current size of the buffer.

Returns:

the value of the count field, which is the number of valid bytes in this output stream.

See Also:

ByteArrayOutputStream.count

toString

public String toString()

Converts the buffer's contents into a string decoding bytes using the platform's default character set. The length of the new String is a function of the character set, and hence may not be equal to the size of the buffer.

This method always replaces malformed-input and unmappable-character sequences with the default replacement string for the platform's default character set. The CharsetDecoder class should be used when more control over the decoding process is required.

Overrides:

toString in class Object

Returns:

String decoded from the buffer's contents.

Since:

JDK1.1

toString

public String toString(String charsetName)
                throws UnsupportedEncodingException

Converts the buffer's contents into a string by decoding the bytes using the specified charsetName. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.

This method always replaces malformed-input and unmappable-character sequences with this charset's default replacement string. The CharsetDecoder class should be used when more control over the decoding process is required.

Parameters:

charsetName - the name of a supported charset

Returns:

String decoded from the buffer's contents.

Throws:

UnsupportedEncodingException - If the named charset is not supported

Since:

JDK1.1

close

public void close()
           throws IOException

Closing can have no effect as we need to access the buffers afterwards. The methods in this class can be called after the stream has been closed without generating an IOException.

The release method MUST be called for this class to release the buffers.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException

release

public void release()
             throws IOException

This really release buffers back to the pool. MUST be called to gain the benefit of pooling.

Throws:

IOException