Package org.apache.commons.io.comparator

Class PathFileComparator

  • All Implemented Interfaces:
    java.io.Serializable, java.util.Comparator<java.io.File>
    public class PathFileComparator
extends java.lang.Object
implements java.io.Serializable
    Compare the path of two files for order (see File.getPath()).

    This comparator can be used to sort lists or arrays of files by their path either in a case-sensitive, case-insensitive or system dependent case sensitive way. A number of singleton instances are provided for the various case sensitivity options (using IOCase) and the reverse of those options.

    Example of a case-sensitive file path sort using the PATH_COMPARATOR singleton instance: 

           List<File> list = ...
       ((AbstractFileComparator) PathFileComparator.PATH_COMPARATOR).sort(list);

    Example of a reverse case-insensitive file path sort using the PATH_INSENSITIVE_REVERSE singleton instance: 

           File[] array = ...
       ((AbstractFileComparator) PathFileComparator.PATH_INSENSITIVE_REVERSE).sort(array);

    Since:
    1.4
    See Also:
    Serialized Form

    • Constructor Summary

      Constructors 
      Constructor Description
      PathFileComparator()
      Construct a case sensitive file path comparator instance.
      PathFileComparator​(IOCase caseSensitivity)
      Construct a file path comparator instance with the specified case-sensitivity.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int compare​(java.io.File file1, java.io.File file2)
      Compare the paths of two files the specified case sensitivity.
      java.io.File[] sort​(java.io.File... files)
      Sort an array of files.
      java.util.List<java.io.File> sort​(java.util.List<java.io.File> files)
      Sort a List of files.
      java.lang.String toString()
      String representation of this file comparator.

      • Methods inherited from class java.lang.Object

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

      • Methods inherited from interface java.util.Comparator

        equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

    • Field Detail

      • PATH_COMPARATOR

        public static final java.util.Comparator<java.io.File> PATH_COMPARATOR
        Case-sensitive path comparator instance (see IOCase.SENSITIVE)

      • PATH_REVERSE

        public static final java.util.Comparator<java.io.File> PATH_REVERSE
        Reverse case-sensitive path comparator instance (see IOCase.SENSITIVE)

      • PATH_INSENSITIVE_COMPARATOR

        public static final java.util.Comparator<java.io.File> PATH_INSENSITIVE_COMPARATOR
        Case-insensitive path comparator instance (see IOCase.INSENSITIVE)

      • PATH_INSENSITIVE_REVERSE

        public static final java.util.Comparator<java.io.File> PATH_INSENSITIVE_REVERSE
        Reverse case-insensitive path comparator instance (see IOCase.INSENSITIVE)

      • PATH_SYSTEM_COMPARATOR

        public static final java.util.Comparator<java.io.File> PATH_SYSTEM_COMPARATOR
        System sensitive path comparator instance (see IOCase.SYSTEM)

      • PATH_SYSTEM_REVERSE

        public static final java.util.Comparator<java.io.File> PATH_SYSTEM_REVERSE
        Reverse system sensitive path comparator instance (see IOCase.SYSTEM)

    • Constructor Detail

      • PathFileComparator

        public PathFileComparator()
        Construct a case sensitive file path comparator instance.

      • PathFileComparator

        public PathFileComparator​(IOCase caseSensitivity)
        Construct a file path comparator instance with the specified case-sensitivity.
        Parameters:
        caseSensitivity - how to handle case sensitivity, null means case-sensitive

    • Method Detail

      • compare

        public int compare​(java.io.File file1,
                   java.io.File file2)
        Compare the paths of two files the specified case sensitivity.
        Specified by:
        compare in interface java.util.Comparator<java.io.File>
        Parameters:
        file1 - The first file to compare
        file2 - The second file to compare
        Returns:
        a negative value if the first file's path is less than the second, zero if the paths are the same and a positive value if the first files path is greater than the second file.

      • toString

        public java.lang.String toString()
        String representation of this file comparator.
        Returns:
        String representation of this file comparator

      • sort

        public java.io.File[] sort​(java.io.File... files)
        Sort an array of files.

        This method uses Arrays.sort(Object[], Comparator) and returns the original array.

        Parameters:
        files - The files to sort, may be null
        Returns:
        The sorted array
        Since:
        2.0

      • sort

        public java.util.List<java.io.File> sort​(java.util.List<java.io.File> files)
        Sort a List of files.

        This method uses Collections.sort(List, Comparator) and returns the original list.

        Parameters:
        files - The files to sort, may be null
        Returns:
        The sorted list
        Since:
        2.0