org.apache.velocity.io
Class VelocityWriter

java.lang.Object
  |
  +--java.io.Writer
        |
        +--org.apache.velocity.io.VelocityWriter

public final class VelocityWriter

extends java.io.Writer

Implementation of a fast Writer. It was originally taken from JspWriter and modified to have less syncronization going on.

Version:

$Id: VelocityWriter.java,v 1.6 2001/10/22 03:53:23 jon Exp $

Author:

Jason van Zyl, Jon S. Stevens, Anil K. Vijendran

Field Summary

protected boolean	autoFlush
protected int	bufferSize
private char[]	cb
static int	DEFAULT_BUFFER constant indicating that the Writer is buffered and is using the implementation default buffer size
private static int	defaultCharBufferSize
private boolean	flushed
private int	nextChar
static int	NO_BUFFER constant indicating that the Writer is not buffering output
static int	UNBOUNDED_BUFFER constant indicating that the Writer is buffered and is unbounded; this is used in BodyContent
private java.io.Writer	writer

Fields inherited from class java.io.Writer

lock, writeBuffer, writeBufferSize

Constructor Summary

private	VelocityWriter(int bufferSize, boolean autoFlush) private constructor.
	VelocityWriter(java.io.Writer writer) Create a buffered character-output stream that uses a default-sized output buffer.
	VelocityWriter(java.io.Writer writer, int sz, boolean autoFlush) Create a new buffered character-output stream that uses an output buffer of the given size.

Method Summary

private void	bufferOverflow()
void	clear() Discard the output buffer.
void	close() Close the stream.
void	flush() Flush the stream.
private void	flushBuffer() Flush the output buffer to the underlying character stream, without flushing the stream itself.
int	getBufferSize() This method returns the size of the buffer used by the JspWriter.
int	getRemaining()
private void	init(java.io.Writer writer, int sz, boolean autoFlush)
boolean	isAutoFlush() This method indicates whether the JspWriter is autoFlushing.
private int	min(int a, int b) Our own little min method, to avoid loading java.lang.Math if we've run out of file descriptors and we're trying to print a stack trace.
void	recycle(java.io.Writer writer) resets this class so that it can be reused
void	write(char[] buf) Write an array of characters.
void	write(char[] cbuf, int off, int len) Write a portion of an array of characters.
void	write(int c) Write a single character.
void	write(java.lang.String s) Write a string.
void	write(java.lang.String s, int off, int len) Write a portion of a String.

Methods inherited from class java.lang.Object

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

Field Detail

NO_BUFFER

public static final int NO_BUFFER

constant indicating that the Writer is not buffering output

DEFAULT_BUFFER

public static final int DEFAULT_BUFFER

constant indicating that the Writer is buffered and is using the implementation default buffer size

UNBOUNDED_BUFFER

public static final int UNBOUNDED_BUFFER

constant indicating that the Writer is buffered and is unbounded; this is used in BodyContent

bufferSize

protected int bufferSize

autoFlush

protected boolean autoFlush

writer

private java.io.Writer writer

cb

private char[] cb

nextChar

private int nextChar

defaultCharBufferSize

private static int defaultCharBufferSize

flushed

private boolean flushed

Constructor Detail

VelocityWriter

public VelocityWriter(java.io.Writer writer)

Create a buffered character-output stream that uses a default-sized output buffer.

Parameters:

response - A Servlet Response

VelocityWriter

private VelocityWriter(int bufferSize,
                       boolean autoFlush)

private constructor.

VelocityWriter

public VelocityWriter(java.io.Writer writer,
                      int sz,
                      boolean autoFlush)

Create a new buffered character-output stream that uses an output buffer of the given size.

Parameters:

response - A Servlet Response

sz - Output-buffer size, a positive integer

Throws:

java.lang.IllegalArgumentException - If sz is <= 0

Method Detail

getBufferSize

public int getBufferSize()

This method returns the size of the buffer used by the JspWriter.

Returns:

the size of the buffer in bytes, or 0 is unbuffered.

isAutoFlush

public boolean isAutoFlush()

This method indicates whether the JspWriter is autoFlushing.

Returns:

if this JspWriter is auto flushing or throwing IOExceptions on buffer overflow conditions

init

private final void init(java.io.Writer writer,
                        int sz,
                        boolean autoFlush)

flushBuffer

private final void flushBuffer()
                        throws java.io.IOException

Flush the output buffer to the underlying character stream, without flushing the stream itself. This method is non-private only so that it may be invoked by PrintStream.

clear

public final void clear()

Discard the output buffer.

bufferOverflow

private final void bufferOverflow()
                           throws java.io.IOException

flush

public final void flush()
                 throws java.io.IOException

Flush the stream.

Overrides:

flush in class java.io.Writer

close

public final void close()
                 throws java.io.IOException

Close the stream.

Overrides:

close in class java.io.Writer

getRemaining

public final int getRemaining()

Returns:

the number of bytes unused in the buffer

write

public final void write(int c)
                 throws java.io.IOException

Write a single character.

Overrides:

write in class java.io.Writer

min

private final int min(int a,
                      int b)

Our own little min method, to avoid loading java.lang.Math if we've run out of file descriptors and we're trying to print a stack trace.

write

public final void write(char[] cbuf,
                        int off,
                        int len)
                 throws java.io.IOException

Write a portion of an array of characters.

Ordinarily this method stores characters from the given array into this stream's buffer, flushing the buffer to the underlying stream as needed. If the requested length is at least as large as the buffer, however, then this method will flush the buffer and write the characters directly to the underlying stream. Thus redundant DiscardableBufferedWriters will not copy data unnecessarily.

Overrides:

write in class java.io.Writer

Parameters:

cbuf - A character array

off - Offset from which to start reading characters

len - Number of characters to write

write

public final void write(char[] buf)
                 throws java.io.IOException

Write an array of characters. This method cannot be inherited from the Writer class because it must suppress I/O exceptions.

Overrides:

write in class java.io.Writer

write

public final void write(java.lang.String s,
                        int off,
                        int len)
                 throws java.io.IOException

Write a portion of a String.

Overrides:

write in class java.io.Writer

Parameters:

s - String to be written

off - Offset from which to start reading characters

len - Number of characters to be written

write

public final void write(java.lang.String s)
                 throws java.io.IOException

Write a string. This method cannot be inherited from the Writer class because it must suppress I/O exceptions.

Overrides:

write in class java.io.Writer

recycle

public final void recycle(java.io.Writer writer)

resets this class so that it can be reused