org.apache.commons.io.comparator

Class NameFileComparator

Implemented Interfaces:
Comparator, Serializable

public class NameFileComparator
extends java.lang.Object
implements Comparator, Serializable

Compare the names of two files for order (see File.getName()).

This comparator can be used to sort lists or arrays of files by their name either in a case-sensitive, case-insensitive or system dependant 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 name sort using the NAME_COMPARATOR singleton instance:

       List<File> list = ...
       Collections.sort(list, NameFileComparator.NAME_COMPARATOR);
 

Example of a reverse case-insensitive file name sort using the NAME_INSENSITIVE_REVERSE singleton instance:

       File[] array = ...
       Arrays.sort(array, NameFileComparator.NAME_INSENSITIVE_REVERSE);
 

Version:
$Revision: 609243 $ $Date: 2008-01-06 00:30:42 +0000 (Sun, 06 Jan 2008) $
Since:
Commons IO 1.4

Field Summary

static Comparator
NAME_COMPARATOR
Case-sensitive name comparator instance (see IOCase.SENSITIVE)
static Comparator
NAME_INSENSITIVE_COMPARATOR
Case-insensitive name comparator instance (see IOCase.INSENSITIVE)
static Comparator
NAME_INSENSITIVE_REVERSE
Reverse case-insensitive name comparator instance (see IOCase.INSENSITIVE)
static Comparator
NAME_REVERSE
Reverse case-sensitive name comparator instance (see IOCase.SENSITIVE)
static Comparator
NAME_SYSTEM_COMPARATOR
System sensitive name comparator instance (see IOCase.SYSTEM)
static Comparator
NAME_SYSTEM_REVERSE
Reverse system sensitive name comparator instance (see IOCase.SYSTEM)
private IOCase
caseSensitivity
Whether the comparison is case sensitive.

Constructor Summary

NameFileComparator()
Construct a case sensitive file name comparator instance.
NameFileComparator(IOCase caseSensitivity)
Construct a file name comparator instance with the specified case-sensitivity.

Method Summary

int
compare(Object obj1, Object obj2)
Compare the names of two files with the specified case sensitivity.

Field Details

NAME_COMPARATOR

public static final Comparator NAME_COMPARATOR

NAME_INSENSITIVE_COMPARATOR

public static final Comparator NAME_INSENSITIVE_COMPARATOR

NAME_INSENSITIVE_REVERSE

public static final Comparator NAME_INSENSITIVE_REVERSE

NAME_REVERSE

public static final Comparator NAME_REVERSE

NAME_SYSTEM_COMPARATOR

public static final Comparator NAME_SYSTEM_COMPARATOR

NAME_SYSTEM_REVERSE

public static final Comparator NAME_SYSTEM_REVERSE

caseSensitivity

private final IOCase caseSensitivity
Whether the comparison is case sensitive.

Constructor Details

NameFileComparator

public NameFileComparator()
Construct a case sensitive file name comparator instance.

NameFileComparator

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

Method Details

compare

public int compare(Object obj1,
                   Object obj2)
Compare the names of two files with the specified case sensitivity.
Parameters:
obj1 - The first file to compare
obj2 - The second file to compare
Returns:
a negative value if the first file's name is less than the second, zero if the names are the same and a positive value if the first files name is greater than the second file.

Copyright (c) 2002-2008 Apache Software Foundation