org.apache.tools.ant.filters
public final class SortFilter extends BaseParamFilterReader implements ChainableReader
Sort a file before and/or after the file.
Examples:
<copy todir="build"> <fileset dir="input" includes="*.txt"/> <filterchain> <sortfilter/> </filterchain> </copy>
Sort all files *.txt
from src location and copy
them into build location. The lines of each file are sorted
in ascendant order comparing the lines via the
String.compareTo(Object o)
method.
<copy todir="build"> <fileset dir="input" includes="*.txt"/> <filterchain> <sortfilter reverse="true"/> </filterchain> </copy>
Sort all files *.txt
from src location into reverse
order and copy them into build location. If reverse parameter has
value true
(default value), then the output line of the files
will be in ascendant order.
<copy todir="build"> <fileset dir="input" includes="*.txt"/> <filterchain> <filterreader classname="org.apache.tools.ant.filters.SortFilter"> <param name="comparator" value="org.apache.tools.ant.filters.EvenFirstCmp"/> </filterreader> </filterchain> </copy>
Sort all files *.txt
from src location using as
sorting criterium EvenFirstCmp
class, that sorts the file
lines putting even lines first then odd lines for example. The modified files
are copied into build location. The EventFirstCmp
,
has to an instanciable class via Class.newInstance()
,
therefore in case of inner class has to be static. It also has to
implement java.util.Comparator
interface, for example:
package org.apache.tools.ant.filters; ...(omitted) public final class EvenFirstCmp implements <b>Comparator</b> { public int compare(Object o1, Object o2) { ...(omitted) } }
The example above is equivalent to:
<componentdef name="evenfirst" classname="org.apache.tools.ant.filters.EvenFirstCmp"/> <copy todir="build"> <fileset dir="input" includes="*.txt"/> <filterchain> <sortfilter> <evenfirst/> </sortfilter> </filterchain> </copy>
If parameter comparator
is present, then
reverse
parameter will not be taken into account.
Since: Ant 1.8.0
Constructor Summary | |
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SortFilter()
Constructor for "dummy" instances.
| |
SortFilter(Reader in)
Creates a new filtered reader.
|
Method Summary | |
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void | add(Comparator comparator)
Set the comparator to be used as sorting criterium as nested element.
|
Reader | chain(Reader rdr)
Creates a new SortReader using the passed in Reader for instantiation.
|
Comparator | getComparator()
Returns the comparator to be used for sorting.
|
boolean | isReverse()
Returns true if the sorting process will be in reverse
order, otherwise the sorting process will be in ascendant order.
|
int | read()
Returns the next character in the filtered stream. |
void | setComparator(Comparator comparator)
Set the comparator to be used as sorting criterium.
|
void | setReverse(boolean reverse)
Sets the sorting process will be in ascendant ( reverse=false )
or to descendant (reverse=true ).
|
See Also: BaseFilterReader
Parameters: in
A Reader object providing the underlying stream. Must not be
null
.
Parameters: comparator the comparator to set
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 comparator
true
if the sorting process will be in reverse
order, otherwise the sorting process will be in ascendant order.
Returns: true
if the sorting process will be in reverse
order, otherwise the sorting process will be in ascendant order.
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
Parameters: comparator the comparator to set
reverse=false
)
or to descendant (reverse=true
).
Parameters: reverse Boolean representing reverse ordering process.