jodd-core/src/main/java/jodd/io/FileUtil.java
public static void cleanDir(final File destDir) throws IOException {
		checkExists(destDir);
		checkIsDirectory(destDir);

		File[] files = destDir.listFiles();
		if (files == null) {
			throw new IOException("Failed to list contents of: " + destDir);
		}

		IOException exception = null;
		for (File file : files) {
			try {
				if (file.isDirectory()) {
					deleteDir(file);
				} else {
					file.delete();
				}
			} catch (IOException ioex) {
				exception = ioex;
				continue;
			}
		}

		if (exception != null) {
			throw exception;
		}
	}
public static void cleanDir(final File destDir) throws IOException {
		checkExists(destDir);
		checkIsDirectory(destDir);

		File[] files = destDir.listFiles();
		if (files == null) {
			throw new IOException("Failed to list contents of: " + destDir);
		}

		IOException exception = null;
		for (File file : files) {
			try {
				if (file.isDirectory()) {
					deleteDir(file);
				} else {
					file.delete();
				}
			} catch (IOException ioex) {
				exception = ioex;
				continue;
			}
		}

		if (exception != null) {
			throw exception;
		}
	}
Cleans a directory without deleting it.

@param destDir destination to clean.
@throws IOException if something went wrong.