Package org.apache.commons.io.comparator
package org.apache.commons.io.comparator
Provides various
Comparator implementations
for Files and Path.
Sorting
All the comparators include convenience utility sort(File...) and
sort(List) methods.
For example, to sort the files in a directory by name:
File[] files = dir.listFiles(); NameFileComparator.NAME_COMPARATOR.sort(files);
...alternatively you can do this in one line:
File[] files = NameFileComparator.NAME_COMPARATOR.sort(dir.listFiles());
Composite Comparator
The CompositeFileComparator can be used to compare (and sort lists or arrays of files) by combining a number of other comparators.
For example, to sort an array of files by type (i.e. directory or file) and then by name:
CompositeFileComparator comparator = new CompositeFileComparator( DirectoryFileComparator.DIRECTORY_COMPARATOR, NameFileComparator.NAME_COMPARATOR); File[] files = dir.listFiles(); comparator.sort(files);
Singleton Instances (thread-safe)
The Comparator implementations have some convenience
singleton(thread-safe) instances ready to use:
- DefaultFileComparator - default file compare:
- DEFAULT_COMPARATOR
- Compare using
File.compareTo(File)method. - DEFAULT_REVERSE
- Reverse compare of
File.compareTo(File)method.
- DEFAULT_COMPARATOR
- Compare using
- DirectoryFileComparator - compare by type (directory or file):
- DIRECTORY_COMPARATOR
- Compare using
File.isDirectory()method (directories < files). - DIRECTORY_REVERSE
- Reverse compare of
File.isDirectory()method (directories >files).
- DIRECTORY_COMPARATOR
- Compare using
- ExtensionFileComparator - compare file extensions:
- EXTENSION_COMPARATOR
- Compare using
FilenameUtils.getExtension(String)method. - EXTENSION_REVERSE
- Reverse compare of
FilenameUtils.getExtension(String)method. - EXTENSION_INSENSITIVE_COMPARATOR
- Case-insensitive compare using
FilenameUtils.getExtension(String)method. - EXTENSION_INSENSITIVE_REVERSE
- Reverse case-insensitive compare of
FilenameUtils.getExtension(String)method. - EXTENSION_SYSTEM_COMPARATOR
- System sensitive compare using
FilenameUtils.getExtension(String)method. - EXTENSION_SYSTEM_REVERSE
- Reverse system sensitive compare of
FilenameUtils.getExtension(String)method.
- EXTENSION_COMPARATOR
- Compare using
- LastModifiedFileComparator
- compare the file's last modified date/time:
- LASTMODIFIED_COMPARATOR
- Compare using
File.lastModified()method. - LASTMODIFIED_REVERSE
- Reverse compare of
File.lastModified()method.
- LASTMODIFIED_COMPARATOR
- Compare using
- NameFileComparator - compare file names:
- NAME_COMPARATOR
- Compare using
File.getName()method. - NAME_REVERSE
- Reverse compare of
File.getName()method. - NAME_INSENSITIVE_COMPARATOR
- Case-insensitive compare using
File.getName()method. - NAME_INSENSITIVE_REVERSE
- Reverse case-insensitive compare of
File.getName()method. - NAME_SYSTEM_COMPARATOR
- System sensitive compare using
File.getName()method. - NAME_SYSTEM_REVERSE
- Reverse system sensitive compare of
File.getName()method.
- NAME_COMPARATOR
- Compare using
- PathFileComparator - compare file paths:
- PATH_COMPARATOR
- Compare using
File.getPath()method. - PATH_REVERSE
- Reverse compare of
File.getPath()method. - PATH_INSENSITIVE_COMPARATOR
- Case-insensitive compare using
File.getPath()method. - PATH_INSENSITIVE_REVERSE
- Reverse case-insensitive compare of
File.getPath()method. - PATH_SYSTEM_COMPARATOR
- System sensitive compare using
File.getPath()method. - PATH_SYSTEM_REVERSE
- Reverse system sensitive compare of
File.getPath()method.
- PATH_COMPARATOR
- Compare using
- SizeFileComparator - compare the file's size:
- SIZE_COMPARATOR
- Compare using
File.length()method (directories treated as zero length). - LASTMODIFIED_REVERSE
- Reverse compare of
File.length()method (directories treated as zero length). - SIZE_SUMDIR_COMPARATOR
- Compare using
FileUtils.sizeOfDirectory(File)method (sums the size of a directory's contents). - SIZE_SUMDIR_REVERSE
- Reverse compare of
FileUtils.sizeOfDirectory(File)method (sums the size of a directory's contents).
- SIZE_COMPARATOR
- Compare using
-
ClassesClassDescriptionCompare two files using a set of delegate file
Comparator.Compares two files using the defaultFile.compareTo(File)method.Compare two files using theFile.isDirectory()method.Compare the file name extensions for order (seeFilenameUtils.getExtension(String)).Compare the last modified date/time of two files for order (seeFileUtils.lastModifiedUnchecked(File)).Compare the names of two files for order (seeFile.getName()).Compare the path of two files for order (seeFile.getPath()).Compare the length/size of two files for order (seeFile.length()andFileUtils.sizeOfDirectory(File)).