org.apache.commons.net.io

Class DotTerminatedMessageWriter


public final class DotTerminatedMessageWriter
extends Writer

DotTerminatedMessageWriter is a class used to write messages to a server that are terminated by a single dot followed by a <CR><LF> sequence and with double dots appearing at the begining of lines which do not signal end of message yet start with a dot. Various Internet protocols such as NNTP and POP3 produce messages of this type.

This class handles the doubling of line-starting periods, converts single linefeeds to NETASCII newlines, and on closing will send the final message terminator dot and NETASCII newline sequence.

Author:
Daniel F. Savarese

Field Summary

private static int
__LAST_WAS_CR_STATE
private static int
__LAST_WAS_NL_STATE
private static int
__NOTHING_SPECIAL_STATE
private Writer
__output
private int
__state

Constructor Summary

DotTerminatedMessageWriter(Writer output)
Creates a DotTerminatedMessageWriter that wraps an existing Writer output destination.

Method Summary

void
close()
Flushes the underlying output, writing all buffered output, but doesn't actually close the underlying stream.
void
flush()
Flushes the underlying output, writing all buffered output.
void
write(String string)
Writes a String to the output.
void
write(String string, int offset, int length)
Writes part of a String to the output starting from a given offset.
void
write(char[] buffer)
Writes a character array to the output.
void
write(char[] buffer, int offset, int length)
Writes a number of characters from a character array to the output starting from a given offset.
void
write(int ch)
Writes a character to the output.

Field Details

__LAST_WAS_CR_STATE

private static final int __LAST_WAS_CR_STATE

Field Value:
1


__LAST_WAS_NL_STATE

private static final int __LAST_WAS_NL_STATE

Field Value:
2


__NOTHING_SPECIAL_STATE

private static final int __NOTHING_SPECIAL_STATE

Field Value:
0


__output

private Writer __output


__state

private int __state

Constructor Details

DotTerminatedMessageWriter

public DotTerminatedMessageWriter(Writer output)
Creates a DotTerminatedMessageWriter that wraps an existing Writer output destination.

Parameters:
output - The Writer output destination to write the message.

Method Details

close

public void close()
            throws IOException
Flushes the underlying output, writing all buffered output, but doesn't actually close the underlying stream. The underlying stream may still be used for communicating with the server and therefore is not closed.


flush

public void flush()
            throws IOException
Flushes the underlying output, writing all buffered output.


write

public void write(String string)
            throws IOException
Writes a String to the output.

Parameters:
string - The String to write.


write

public void write(String string,
                  int offset,
                  int length)
            throws IOException
Writes part of a String to the output starting from a given offset.

Parameters:
string - The String to write.
offset - The offset into the String at which to start copying data.
length - The number of characters to write.


write

public void write(char[] buffer)
            throws IOException
Writes a character array to the output.

Parameters:
buffer - The character array to write.


write

public void write(char[] buffer,
                  int offset,
                  int length)
            throws IOException
Writes a number of characters from a character array to the output starting from a given offset.

Parameters:
buffer - The character array to write.
offset - The offset into the array at which to start copying data.
length - The number of characters to write.


write

public void write(int ch)
            throws IOException
Writes a character to the output. Note that a call to this method may result in multiple writes to the underling Writer in order to convert naked linefeeds to NETASCII line separators and to double line-leading periods. This is transparent to the programmer and is only mentioned for completeness.

Parameters:
ch - The character to write.