org.apache.commons.io.comparator

Class PathFileComparator

java.lang.Object

org.apache.commons.io.comparator.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);
 

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>	PATH_COMPARATOR Case-sensitive path comparator instance (see IOCase.SENSITIVE)
static java.util.Comparator<java.io.File>	PATH_INSENSITIVE_COMPARATOR Case-insensitive path comparator instance (see IOCase.INSENSITIVE)
static java.util.Comparator<java.io.File>	PATH_INSENSITIVE_REVERSE Reverse case-insensitive path comparator instance (see IOCase.INSENSITIVE)
static java.util.Comparator<java.io.File>	PATH_REVERSE Reverse case-sensitive path comparator instance (see IOCase.SENSITIVE)
static java.util.Comparator<java.io.File>	PATH_SYSTEM_COMPARATOR System sensitive path comparator instance (see IOCase.SYSTEM)
static java.util.Comparator<java.io.File>	PATH_SYSTEM_REVERSE Reverse system sensitive path comparator instance (see IOCase.SYSTEM)

Constructor Summary

Constructors

Constructor and Description
PathFileComparator() Constructs a case-sensitive file path comparator instance.
PathFileComparator(IOCase ioCase) Constructs a file path comparator instance with the specified case-sensitivity.

Method Summary

Modifier and Type	Method and Description
int	compare(java.io.File file1, java.io.File file2) Compares the paths of two files the specified case sensitivity.
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

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()

Constructs a case-sensitive file path comparator instance.

PathFileComparator

public PathFileComparator(IOCase ioCase)

Constructs a file path comparator instance with the specified case-sensitivity.

Parameters:

ioCase - how to handle case sensitivity, null means case-sensitive

Method Detail

compare

public int compare(java.io.File file1,
                   java.io.File file2)

Compares 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)

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