org.apache.commons.io.comparator

Class LastModifiedFileComparator

java.lang.Object

org.apache.commons.io.comparator.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 and 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.

Constructor Summary

Constructors

Constructor and Description
LastModifiedFileComparator()

Method Summary

Modifier and Type	Method and 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

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, 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.