org.apache.commons.io.comparator

Class NameFileComparator

java.lang.Object

org.apache.commons.io.comparator.NameFileComparator

All Implemented Interfaces:

java.io.Serializable, java.util.Comparator

public class NameFileComparator
extends java.lang.Object
implements java.util.Comparator, java.io.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);
 

Since:

Commons IO 1.4

Version:

$Revision: 609243 $ $Date: 2008-01-06 00:30:42 +0000 (Sun, 06 Jan 2008) $

See Also:

Serialized Form

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor and Description
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

Methods

Modifier and Type	Method and Description
int	compare(java.lang.Object obj1, java.lang.Object obj2) Compare the names of two files with the specified case sensitivity.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals

Field Detail

NAME_COMPARATOR

public static final java.util.Comparator NAME_COMPARATOR

Case-sensitive name comparator instance (see IOCase.SENSITIVE)

NAME_REVERSE

public static final java.util.Comparator NAME_REVERSE

Reverse case-sensitive name comparator instance (see IOCase.SENSITIVE)

NAME_INSENSITIVE_COMPARATOR

public static final java.util.Comparator NAME_INSENSITIVE_COMPARATOR

Case-insensitive name comparator instance (see IOCase.INSENSITIVE)

NAME_INSENSITIVE_REVERSE

public static final java.util.Comparator NAME_INSENSITIVE_REVERSE

Reverse case-insensitive name comparator instance (see IOCase.INSENSITIVE)

NAME_SYSTEM_COMPARATOR

public static final java.util.Comparator NAME_SYSTEM_COMPARATOR

System sensitive name comparator instance (see IOCase.SYSTEM)

NAME_SYSTEM_REVERSE

public static final java.util.Comparator NAME_SYSTEM_REVERSE

Reverse system sensitive name comparator instance (see IOCase.SYSTEM)

caseSensitivity

private final IOCase caseSensitivity

Whether the comparison is case sensitive.

Constructor Detail

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 Detail

compare

public int compare(java.lang.Object obj1,
          java.lang.Object obj2)

Compare the names of two files with the specified case sensitivity.

Specified by:

compare in interface java.util.Comparator

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.