org.apache.tools.ant.filters

Class TailFilter

public final class TailFilter extends BaseParamFilterReader implements ChainableReader

Reads the last n lines of a stream. (Default is last10 lines.) Example:

<tailfilter lines="3"/>

Or:

<filterreader classname="org.apache.tools.ant.filters.TailFilter">
   <param name="lines" value="3"/>
 </filterreader>

Constructor Summary
	TailFilter() Constructor for "dummy" instances.
	TailFilter(Reader in) Creates a new filtered reader.

Method Summary
Reader	chain(Reader rdr) Creates a new TailFilter using the passed in Reader for instantiation.
int	read() Returns the next character in the filtered stream.
void	setLines(long lines) Sets the number of lines to be returned in the filtered stream.
void	setSkip(long skip) Sets the number of lines to be skipped in the filtered stream.

Constructor Detail

TailFilter

public TailFilter()

Constructor for "dummy" instances.

TailFilter

public TailFilter(Reader in)

Creates a new filtered reader.

Parameters: in A Reader object providing the underlying stream. Must not be null.

Method Detail

chain

public Reader chain(Reader rdr)

Creates a new TailFilter using the passed in Reader for instantiation.

Parameters: rdr A Reader object providing the underlying stream. Must not be null.

Returns: a new filter based on this configuration, but filtering the specified reader

Returns the next character in the filtered stream. If the read-ahead has been completed, the next character in the buffer is returned. Otherwise, the stream is read to the end and buffered (with the buffer growing as necessary), then the appropriate position in the buffer is set to read from.

Returns: the next character in the resulting stream, or -1 if the end of the resulting stream has been reached

Throws: IOException if the underlying stream throws an IOException during reading

setLines

public void setLines(long lines)

Sets the number of lines to be returned in the filtered stream.

Parameters: lines the number of lines to be returned in the filtered stream

setSkip

public void setSkip(long skip)

Sets the number of lines to be skipped in the filtered stream.

Parameters: skip the number of lines to be skipped in the filtered stream