jodd-core/src/main/java/jodd/io/FileUtil.java
public static void appendBytes(final File dest, final byte[] data, final int off, final int len) throws IOException {
		outBytes(dest, data, off, len, true);
	}
public static void appendBytes(final File dest, final byte[] data, final int off, final int len) throws IOException {
		outBytes(dest, data, off, len, true);
	}
Appends bytes. append = true

@see #outBytes(File, byte[], int, int, boolean)