Here you can find the source of compareTo(final byte[] left, final byte[] right)
public static int compareTo(final byte[] left, final byte[] right)
//package com.java2s; public class Main { public static int compareTo(final byte[] left, final byte[] right) { return compareTo(left, 0, left.length, right, 0, right.length); }/*w w w. ja va 2 s . co m*/ public static int compareTo(byte[] buffer1, int offset1, int length1, byte[] buffer2, int offset2, int length2) { // Bring WritableComparator code local int end1 = offset1 + length1; int end2 = offset2 + length2; for (int i = offset1, j = offset2; i < end1 && j < end2; i++, j++) { int a = (buffer1[i] & 0xff); int b = (buffer2[j] & 0xff); if (a != b) { return a - b; } } return length1 - length2; } }