org.apache.xml.serializer
Class SerializerTraceWriter

java.lang.Object
  java.io.Writer
      org.apache.xml.serializer.SerializerTraceWriter

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable, java.lang.Appendable, WriterChain

final class SerializerTraceWriter
extends java.io.Writer
implements WriterChain

This class wraps the real writer, it only purpose is to send CHARACTERTOSTREAM events to the trace listener. Each method immediately sends the call to the wrapped writer unchanged, but in addition it collects characters to be issued to a trace listener. In this way the trace listener knows what characters have been written to the output Writer. There may still be differences in what the trace events say is going to the output writer and what is really going there. These differences will be due to the fact that this class is UTF-8 encoding before emiting the trace event and the underlying writer may not be UTF-8 encoding. There may also be encoding differences. So the main pupose of this class is to provide a resonable facsimile of the true output.

Field Summary

private byte[]	buf Internal buffer to collect the characters to go to the trace listener.
private int	buf_length The size of the internal buffer, just to keep too many events from being sent to the tracer
private int	count How many bytes have been collected and still need to go to trace listener.
private SerializerTrace	m_tracer The tracer to send events to
private java.io.Writer	m_writer The real writer to immediately write to.

Fields inherited from class java.io.Writer

lock

Constructor Summary

SerializerTraceWriter(java.io.Writer out, SerializerTrace tracer)
Constructor.

Method Summary

void	close() Flush the internal buffer and close the Writer
void	flush() Flush the internal buffer and flush the Writer
private void	flushBuffer() Flush out the collected characters by sending them to the trace listener.
java.io.OutputStream	getOutputStream() Get the OutputStream that is the at the end of the chain of writers.
java.io.Writer	getWriter() Get the writer that this one directly wraps.
private void	setBufferSize(int size) Creates or replaces the internal buffer, and makes sure it has a few extra bytes slight overflow of the last UTF8 encoded character.
void	write(char[] chars, int start, int length) 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.

Methods inherited from class java.io.Writer

append, append, append, write, write

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.xml.serializer.WriterChain

write, write

Field Detail

m_writer

private final java.io.Writer m_writer

The real writer to immediately write to. This reference may be null, in which case nothing is written out, but only the trace events are fired for output.

m_tracer

private final SerializerTrace m_tracer

The tracer to send events to

buf_length

private int buf_length

The size of the internal buffer, just to keep too many events from being sent to the tracer

buf

private byte[] buf

Internal buffer to collect the characters to go to the trace listener.

count

private int count

How many bytes have been collected and still need to go to trace listener.

Constructor Detail

SerializerTraceWriter

public SerializerTraceWriter(java.io.Writer out,
                             SerializerTrace tracer)

Constructor. If the writer passed in is null, then this SerializerTraceWriter will only signal trace events of what would have been written to that writer. If the writer passed in is not null then the trace events will mirror what is going to that writer. In this way tools, such as a debugger, can gather information on what is being written out.

Parameters:

out - the Writer to write to (possibly null)

tracer - the tracer to inform that characters are being written

Method Detail

setBufferSize

private void setBufferSize(int size)

Creates or replaces the internal buffer, and makes sure it has a few extra bytes slight overflow of the last UTF8 encoded character.

Parameters:

size -

flushBuffer

private void flushBuffer()
                  throws java.io.IOException

Flush out the collected characters by sending them to the trace listener. These characters are never written to the real writer (m_writer) because that has already happened with every method call. This method simple informs the listener of what has already happened.

Throws:

java.io.IOException

flush

public void flush()
           throws java.io.IOException

Flush the internal buffer and flush the Writer

Specified by:

flush in interface java.io.Flushable

Specified by:

flush in interface WriterChain

Specified by:

flush in class java.io.Writer

Throws:

java.io.IOException

See Also:

Writer.flush()

close

public void close()
           throws java.io.IOException

Flush the internal buffer and close the Writer

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface WriterChain

Specified by:

close in class java.io.Writer

Throws:

java.io.IOException

See Also:

Writer.close()

write

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

Write a single character. The character to be written is contained in the 16 low-order bits of the given integer value; the 16 high-order bits are ignored.

Subclasses that intend to support efficient single-character output should override this method.

Specified by:

write in interface WriterChain

Overrides:

write in class java.io.Writer

Parameters:

c - int specifying a character to be written.

Throws:

java.io.IOException - If an I/O error occurs

write

public void write(char[] chars,
                  int start,
                  int length)
           throws java.io.IOException

Write a portion of an array of characters.

Specified by:

write in interface WriterChain

Specified by:

write in class java.io.Writer

Parameters:

chars - Array of characters

start - Offset from which to start writing characters

length - Number of characters to write

Throws:

java.io.IOException - If an I/O error occurs

java.io.IOException

write

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

Write a string.

Specified by:

write in interface WriterChain

Overrides:

write in class java.io.Writer

Parameters:

s - String to be written

Throws:

java.io.IOException - If an I/O error occurs

getWriter

public java.io.Writer getWriter()

Get the writer that this one directly wraps.

Specified by:

getWriter in interface WriterChain

getOutputStream

public java.io.OutputStream getOutputStream()

Get the OutputStream that is the at the end of the chain of writers.

Specified by:

getOutputStream in interface WriterChain