Package org.apache.commons.io.comparator

Class LastModifiedFileComparator

  • All Implemented Interfaces:
    java.io.Serializable, java.util.Comparator<java.io.File>
    public class LastModifiedFileComparator
extends java.lang.Object
implements java.io.Serializable
    Compare the last modified date/time of two files for order (see FileUtils.lastModifiedUnchecked(File)).

    This comparator can be used to sort lists or arrays of files by their last modified date/time.

    Example of sorting a list of files using the LASTMODIFIED_COMPARATOR singleton instance: 

           List<File> list = ...
       ((AbstractFileComparator) LastModifiedFileComparator.LASTMODIFIED_COMPARATOR).sort(list);

    Example of doing a reverse sort of an array of files using the LASTMODIFIED_REVERSE singleton instance: 

           File[] array = ...
       ((AbstractFileComparator) LastModifiedFileComparator.LASTMODIFIED_REVERSE).sort(array);

    Deprecating Serialization

    Serialization is deprecated and will be removed in 3.0.

    Since:
    1.4
    See Also:
    Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.util.Comparator<java.io.File> LASTMODIFIED_COMPARATOR
      Last modified comparator instance.
      static java.util.Comparator<java.io.File> LASTMODIFIED_REVERSE
      Reverse last modified comparator instance.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int compare​(java.io.File file1, java.io.File file2)
      Compares the last modified date/time of two files.
      java.io.File[] sort​(java.io.File... files)
      Sorts an array of files.
      java.util.List<java.io.File> sort​(java.util.List<java.io.File> files)
      Sorts a List of files.
      java.lang.String toString()
      String representation of this file comparator.

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.util.Comparator

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

    • Field Detail

      • LASTMODIFIED_COMPARATOR

        public static final java.util.Comparator<java.io.File> LASTMODIFIED_COMPARATOR
        Last modified comparator instance.

      • LASTMODIFIED_REVERSE

        public static final java.util.Comparator<java.io.File> LASTMODIFIED_REVERSE
        Reverse last modified comparator instance.

    • Constructor Detail

      • LastModifiedFileComparator

        public LastModifiedFileComparator()

    • Method Detail

      • compare

        public int compare​(java.io.File file1,
                   java.io.File file2)
        Compares the last modified date/time of two files.
        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 last modified date/time is less than the second, zero if the last modified date/time are the same and a positive value if the first files last modified date/time is greater than the second file.

      • sort

        public java.io.File[] sort​(java.io.File... files)
        Sorts 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)
        Sorts a List of files.

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

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

      • toString

        public java.lang.String toString()
        String representation of this file comparator.
        Overrides:
        toString in class java.lang.Object
        Returns:
        String representation of this file comparator.