Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
import java.io.ByteArrayOutputStream;

public class Main {
    public static final byte[] FirstPadding = { (byte) 0x80 };
    public static final byte[] ZeroPadding = { (byte) 0x00 };

    public static byte[] padding(byte[] source) throws Exception {
        if (source.length >= 0x2000000000000000l) {
            throw new Exception();
        }
        long l = source.length * 8;
        long k = 448 - (l + 1) % 512;
        if (k < 0) {
            k = k + 512;
        }
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        baos.write(source);
        baos.write(FirstPadding);
        long i = k - 7;
        while (i > 0) {
            baos.write(ZeroPadding);
            i -= 8;
        }
        baos.write(long2bytes(l));
        return baos.toByteArray();
    }

    public static byte[] long2bytes(long l) {
        byte[] bytes = new byte[8];
        for (int i = 0; i < 8; i++) {
            bytes[i] = (byte) (l >>> ((7 - i) * 8));
        }
        return bytes;
    }

    public static byte[] toByteArray(int a, int b, int c, int d, int e, int f, int g, int h) throws Exception {
        ByteArrayOutputStream baos = new ByteArrayOutputStream(32);
        baos.write(toByteArray(a));
        baos.write(toByteArray(b));
        baos.write(toByteArray(c));
        baos.write(toByteArray(d));
        baos.write(toByteArray(e));
        baos.write(toByteArray(f));
        baos.write(toByteArray(g));
        baos.write(toByteArray(h));
        return baos.toByteArray();
    }

    public static byte[] toByteArray(int i) {
        byte[] byteArray = new byte[4];
        byteArray[0] = (byte) (i >>> 24);
        byteArray[1] = (byte) ((i & 0xFFFFFF) >>> 16);
        byteArray[2] = (byte) ((i & 0xFFFF) >>> 8);
        byteArray[3] = (byte) (i & 0xFF);
        return byteArray;
    }
}