org.apache.tools.ant.filters

Class TailFilter

Implemented Interfaces:
ChainableReader, Parameterizable

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.

Methods inherited from class org.apache.tools.ant.filters.BaseParamFilterReader

getParameters, setParameters

Methods inherited from class org.apache.tools.ant.filters.BaseFilterReader

getInitialized, getProject, read, readFully, readLine, setInitialized, setProject, skip

Constructor Details

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 Details

chain

public final Reader chain(Reader rdr)
Creates a new TailFilter using the passed in Reader for instantiation.
Specified by:
chain in interface ChainableReader
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

read

public final int read()
            throws IOException
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

setLines

public final 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 final 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

Copyright B) 2000-2007 Apache Software Foundation. All Rights Reserved.