src/org/kocakosm/pitaya/io/XFiles.java
public static byte[] head(File f, int n) throws IOException
	{
		Parameters.checkCondition(n >= 0);
		InputStream in = newInputStream(f);
		byte[] buf = new byte[n];
		try {
			return XArrays.copyOf(buf, 0, in.read(buf));
		} finally {
			IO.close(in);
		}
	}
public static byte[] head(File f, int n) throws IOException
	{
		Parameters.checkCondition(n >= 0);
		InputStream in = newInputStream(f);
		byte[] buf = new byte[n];
		try {
			return XArrays.copyOf(buf, 0, in.read(buf));
		} finally {
			IO.close(in);
		}
	}
Reads the first (up to {@code n}) bytes of the given {@code File}.
Named after the Unix command of the same name.

@param f the file to read.
@param n the maximum number of bytes to read.

@return the first bytes of the given {@code File}.

@throws NullPointerException if {@code f} is {@code null}.
@throws IllegalArgumentException if {@code n} is negative.
@throws IOException if {@code f} does not exist, or if it is a
directory rather than a regular file, or if it can't be read.
@throws SecurityException if a security manager exists and denies
read access to {@code f}.