? EmptyFileFilter
java.lang.Object
org.apache.commons.io.filefilter.AbstractFileFilter
org.apache.commons.io.filefilter.EmptyFileFilter
- ????????:
FileFilter
,FilenameFilter
,Serializable
,FileVisitor<Path>
,PathFilter
,PathVisitor
,IOFileFilter
This filter accepts files or directories that are empty.
If the File
is a directory it checks that it contains no files.
Example, showing how to print out a list of the current directory's empty files/directories:
Using Classic IO
File dir = new File("."); String[] files = dir.list(EmptyFileFilter.EMPTY); for (String file : files) { System.out.println(file); }
Example, showing how to print out a list of the current directory's non-empty files/directories:
File dir = new File("."); String[] files = dir.list(EmptyFileFilter.NOT_EMPTY); for (String file : files) { System.out.println(file); }
Using NIO
final Path dir = Paths.get(""); final AccumulatorPathVisitor visitor = AccumulatorPathVisitor.withLongCounters(EmptyFileFilter.EMPTY); // // Walk one dir Files.walkFileTree(dir, Collections.emptySet(), 1, visitor); System.out.println(visitor.getPathCounters()); System.out.println(visitor.getFileList()); // visitor.getPathCounters().reset(); // // Walk dir tree Files.walkFileTree(dir, visitor); System.out.println(visitor.getPathCounters()); System.out.println(visitor.getDirList()); System.out.println(visitor.getFileList());
- ???????:
- 1.3
- ????:
-
????
????????????static final IOFileFilter
Singleton instance of empty filterstatic final IOFileFilter
Singleton instance of not-empty filter???????? org.apache.commons.io.filefilter.IOFileFilter
EMPTY_STRING_ARRAY
-
?????
??? -
????
??????????boolean
Checks to see if the file is empty.accept
(Path file, BasicFileAttributes attributes) Checks to see if the file is empty.??????? org.apache.commons.io.filefilter.AbstractFileFilter
accept, handle, postVisitDirectory, preVisitDirectory, toString, visitFile, visitFileFailed
??????? java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
???????? org.apache.commons.io.filefilter.IOFileFilter
and, negate, or
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??????
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EMPTY
Singleton instance of empty filter -
NOT_EMPTY
Singleton instance of not-empty filter
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-
???????
-
EmptyFileFilter
protected EmptyFileFilter()Restrictive constructor.
-
-
??????
-
accept
Checks to see if the file is empty.- ???:
accept
????FileFilter
- ???:
accept
????IOFileFilter
- ??:
accept
???AbstractFileFilter
- ??:
file
- the file or directory to check- ??:
true
if the file or directory is empty, otherwisefalse
.
-
accept
Checks to see if the file is empty.- ???:
accept
????IOFileFilter
- ???:
accept
????PathFilter
- ??:
file
- the file or directory to checkattributes
- the file's basic attributes (TODO may be null).- ??:
true
if the file or directory is empty, otherwisefalse
.- ???????:
- 2.9.0
-