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 * (the "License"); you may not use this file except in compliance with
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 *      http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.commons.io.comparator;

import java.io.File;
import java.io.Serializable;
import java.util.Comparator;

import org.apache.commons.io.IOCase;

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);

Since:1.4
/** * Compare the <b>path</b> of two files for order (see {@link File#getPath()}). * <p> * 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 {@link IOCase}) * and the reverse of those options. * <p> * Example of a <i>case-sensitive</i> file path sort using the * {@link #PATH_COMPARATOR} singleton instance: * <pre> * List&lt;File&gt; list = ... * ((AbstractFileComparator) PathFileComparator.PATH_COMPARATOR).sort(list); * </pre> * <p> * Example of a <i>reverse case-insensitive</i> file path sort using the * {@link #PATH_INSENSITIVE_REVERSE} singleton instance: * <pre> * File[] array = ... * ((AbstractFileComparator) PathFileComparator.PATH_INSENSITIVE_REVERSE).sort(array); * </pre> * <p> * * @since 1.4 */
public class PathFileComparator extends AbstractFileComparator implements Serializable { private static final long serialVersionUID = 6527501707585768673L;
Case-sensitive path comparator instance (see IOCase.SENSITIVE)
/** Case-sensitive path comparator instance (see {@link IOCase#SENSITIVE}) */
public static final Comparator<File> PATH_COMPARATOR = new PathFileComparator();
Reverse case-sensitive path comparator instance (see IOCase.SENSITIVE)
/** Reverse case-sensitive path comparator instance (see {@link IOCase#SENSITIVE}) */
public static final Comparator<File> PATH_REVERSE = new ReverseComparator(PATH_COMPARATOR);
Case-insensitive path comparator instance (see IOCase.INSENSITIVE)
/** Case-insensitive path comparator instance (see {@link IOCase#INSENSITIVE}) */
public static final Comparator<File> PATH_INSENSITIVE_COMPARATOR = new PathFileComparator(IOCase.INSENSITIVE);
Reverse case-insensitive path comparator instance (see IOCase.INSENSITIVE)
/** Reverse case-insensitive path comparator instance (see {@link IOCase#INSENSITIVE}) */
public static final Comparator<File> PATH_INSENSITIVE_REVERSE = new ReverseComparator(PATH_INSENSITIVE_COMPARATOR);
System sensitive path comparator instance (see IOCase.SYSTEM)
/** System sensitive path comparator instance (see {@link IOCase#SYSTEM}) */
public static final Comparator<File> PATH_SYSTEM_COMPARATOR = new PathFileComparator(IOCase.SYSTEM);
Reverse system sensitive path comparator instance (see IOCase.SYSTEM)
/** Reverse system sensitive path comparator instance (see {@link IOCase#SYSTEM}) */
public static final Comparator<File> PATH_SYSTEM_REVERSE = new ReverseComparator(PATH_SYSTEM_COMPARATOR);
Whether the comparison is case sensitive.
/** Whether the comparison is case sensitive. */
private final IOCase caseSensitivity;
Construct a case sensitive file path comparator instance.
/** * Construct a case sensitive file path comparator instance. */
public PathFileComparator() { this.caseSensitivity = IOCase.SENSITIVE; }
Construct a file path comparator instance with the specified case-sensitivity.
Params:
  • caseSensitivity – how to handle case sensitivity, null means case-sensitive
/** * Construct a file path comparator instance with the specified case-sensitivity. * * @param caseSensitivity how to handle case sensitivity, null means case-sensitive */
public PathFileComparator(final IOCase caseSensitivity) { this.caseSensitivity = caseSensitivity == null ? IOCase.SENSITIVE : caseSensitivity; }
Compare the paths of two files the specified case sensitivity.
Params:
  • 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.
/** * Compare the paths of two files the specified case sensitivity. * * @param file1 The first file to compare * @param file2 The second file to compare * @return 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. * */
@Override public int compare(final File file1, final File file2) { return caseSensitivity.checkCompareTo(file1.getPath(), file2.getPath()); }
String representation of this file comparator.
Returns:String representation of this file comparator
/** * String representation of this file comparator. * * @return String representation of this file comparator */
@Override public String toString() { return super.toString() + "[caseSensitivity=" + caseSensitivity + "]"; } }