com.groupbyinc.common.apache.commons.io.filefilter.package.html Maven / Gradle / Ivy
This package defines an interface (IOFileFilter) that combines both
{@link java.io.FileFilter} and {@link java.io.FilenameFilter}. Besides
that the package offers a series of ready-to-use implementations of the
IOFileFilter interface including implementation that allow you to combine
other such filters.
These filter can be used to list files or in {@link java.awt.FileDialog},
for example.
There are a number of 'primitive' filters:
DirectoryFilter
Only accept directories
PrefixFileFilter
Filter based on a prefix
SuffixFileFilter
Filter based on a suffix
NameFileFilter
Filter based on a filename
WildcardFileFilter
Filter based on wildcards
AgeFileFilter
Filter based on last modified time of file
SizeFileFilter
Filter based on file size
And there are five 'boolean' filters:
TrueFileFilter
Accept all files
FalseFileFilter
Accept no files
NotFileFilter
Applies a logical NOT to an existing filter
AndFileFilter
Combines two filters using a logical AND
OrFileFilter
Combines two filter using a logical OR
These boolean FilenameFilters can be nested, to allow arbitrary expressions.
For example, here is how one could print all non-directory files in the
current directory, starting with "A", and ending in ".java" or ".class":
File dir = new File(".");
String[] files = dir.list(
new AndFileFilter(
new AndFileFilter(
new PrefixFileFilter("A"),
new OrFileFilter(
new SuffixFileFilter(".class"),
new SuffixFileFilter(".java")
)
),
new NotFileFilter(
new DirectoryFileFilter()
)
)
);
for ( int i=0; i<files.length; i++ ) {
System.out.println(files[i]);
}
This package also contains a utility class:
FileFilterUtils. It allows you to use all
file filters without having to put them in the import section. Here's how the
above example will look using FileFilterUtils:
File dir = new File(".");
String[] files = dir.list(
FileFilterUtils.andFileFilter(
FileFilterUtils.andFileFilter(
FileFilterUtils.prefixFileFilter("A"),
FileFilterUtils.orFileFilter(
FileFilterUtils.suffixFileFilter(".class"),
FileFilterUtils.suffixFileFilter(".java")
)
),
FileFilterUtils.notFileFilter(
FileFilterUtils.directoryFileFilter()
)
)
);
for ( int i=0; i<files.length; i++ ) {
System.out.println(files[i]);
}
There are a few other goodies in that class so please have a look at the
documentation in detail.