Code example for Adler32

 
    /** 
     * Returns the checksum of all but the first 12 bytes of {@code dex}. 
     */ 
    public int computeChecksum(DexBuffer dex) throws IOException {
        Adler32 adler32 = new Adler32();
        int offset = CHECKSUM_OFFSET + CHECKSUM_SIZE;
 
        byte[] bytes = dex.getBytes();
        adler32.update(bytes, offset, bytes.length - offset);
        return (int) adler32.getValue();
    } 
 
    /** 
     * Generates the signature and checksum of the dex file {@code out} and 
     * writes them to the file. 
     */ 
    public void writeHashes(DexBuffer dex) throws IOException {
        byte[] signature = computeSignature(dex);
        dex.open(SIGNATURE_OFFSET).write(signature);