Example

The following example pads an input buffer, transforms the padded buffer with already-initialized IMode instances, then unpads the output buffer.

     IPad padding = IPad.getInstance("PKCS7");
     padding.init(blockSize);
     byte[] pad = padding.pad(input, 0, input.length);
     byte[] pt = new byte[input.length + pad.length];
     byte[] ct = new byte[pt.length];
     byte[] cpt = new byte[pt.length];
     System.arraycopy(input, 0, pt, 0, input.length);
     System.arraycopy(pad, 0, pt, input.length, pad.length);
     
     for (int i = 0; i + blockSize < pt.length; i += blockSize)
        {
           enc.update(pt, i, ct, i);
        }
     
     for (int i = 0; i + blockSize < ct.length; i += blockSize)
        {
           dec.update(ct, i, cpt, i);
        }
     
     int unpad = padding.unpad(cpt, 0, cpt.length);
     byte[] output = new byte[cpt.length - unpad];
     System.arraycopy(cpt, 0, output, 0, output.length);