Package org.apache.commons.io.filefilter

# Class HiddenFileFilter

java.lang.Object
org.apache.commons.io.filefilter.AbstractFileFilter
org.apache.commons.io.filefilter.HiddenFileFilter

All Implemented Interfaces:
  `FileFilter`, `FilenameFilter`, `Serializable`, `FileVisitor<Path>`, `PathMatcher`, `PathFilter`, `PathVisitor`, `IOFileFilter`

public class HiddenFileFilter extends AbstractFileFilter implements Serializable
This filter accepts `File`s that are hidden.

Example, showing how to print out a list of the current directory's hidden files:

## Using Classic IO

     File dir = FileUtils.current();
     String[] files = dir.list(HiddenFileFilter.HIDDEN);
     for (String file : files) {
         System.out.println(file);
     }

Example, showing how to print out a list of the current directory's visible (i.e. not hidden) files:

     File dir = FileUtils.current();
     String[] files = dir.list(HiddenFileFilter.VISIBLE);
     for (String file : files) {
         System.out.println(file);
     }

## Using NIO

     final Path dir = PathUtils.current();
     final AccumulatorPathVisitor visitor = AccumulatorPathVisitor.withLongCounters(HiddenFileFilter.HIDDEN);
     //
     // 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());

## Deprecating Serialization

Serialization is deprecated and will be removed in 3.0.

Since:
  1.3
See Also:
  - Serialized Form

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final IOFileFilter`
  `HIDDEN`
  Singleton instance of hidden filter
  `static final IOFileFilter`
  `VISIBLE`
  Singleton instance of visible filter

  ### Fields inherited from interface org.apache.commons.io.filefilter.IOFileFilter

  `EMPTY_STRING_ARRAY`

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `HiddenFileFilter()`
  Restrictive constructor.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `boolean`
  `accept(File file)`
  Checks to see if the file is hidden.
  `FileVisitResult`
  `accept(Path file, BasicFileAttributes attributes)`
  Checks to see if the file is hidden.

  ### Methods inherited from class org.apache.commons.io.filefilter.AbstractFileFilter

  `accept, handle, postVisitDirectory, preVisitDirectory, toString, visitFile, visitFileFailed`

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

  ### Methods inherited from interface org.apache.commons.io.filefilter.IOFileFilter

  `and, matches, negate, or`

- ## Field Details

  - ### HIDDEN

    public static final IOFileFilter HIDDEN
    Singleton instance of hidden filter

  - ### VISIBLE

    public static final IOFileFilter VISIBLE
    Singleton instance of visible filter

- ## Constructor Details

  - ### HiddenFileFilter

    protected HiddenFileFilter()
    Restrictive constructor.

- ## Method Details

  - ### accept

    public boolean accept(File file)
    Checks to see if the file is hidden.
    Specified by:
      `accept` in interface `FileFilter`
    Specified by:
      `accept` in interface `IOFileFilter`
    Overrides:
      `accept` in class `AbstractFileFilter`
    Parameters:
      `file` - the File to check
    Returns:
      `true` if the file is hidden, otherwise `false`.

  - ### accept

    public FileVisitResult accept(Path file, BasicFileAttributes attributes)
    Checks to see if the file is hidden.
    Specified by:
      `accept` in interface `IOFileFilter`
    Specified by:
      `accept` in interface `PathFilter`
    Parameters:
      `file` - the File to check
      `attributes` - the file's basic attributes (TODO may be null).
    Returns:
      `true` if the file is hidden, otherwise `false`.
    Since:
      2.9.0