fitgoodies-core/src/main/java/de/cologneintelligence/fitgoodies/file/FileSelector.java
public File getUniqueFile()
			throws FilenameNotUniqueException, FileNotFoundException {
		File[] files = directory.listFiles(filter);

		if (files == null || files.length == 0) {
			throw new FileNotFoundException();
		}

		if (files.length > 1) {
			throw new FilenameNotUniqueException(filter.getPattern());
		}
		return files[0];
	}
public File getUniqueFile()
			throws FilenameNotUniqueException, FileNotFoundException {
		File[] files = directory.listFiles(filter);

		if (files == null || files.length == 0) {
			throw new FileNotFoundException();
		}

		if (files.length > 1) {
			throw new FilenameNotUniqueException(filter.getPattern());
		}
		return files[0];
	}
Returns the only file that matches the pattern. If no file matches, a
<code>null</code>. If more than one file matches, a
{@link FilenameNotUniqueException} is thrown.

@return the matching file or <code>null</code> if no file matched
@throws FilenameNotUniqueException more than one file matched the pattern
@throws FileNotFoundException      thrown, if the directory does not exist.