code: public boolean
  verify(byte [] signature, boolean truncation_ok) {
  	byte [] expected = sign();
  	if (truncation_ok && signature.length < expected.length) {
  		byte [] truncated = new byte[signature.length];
  		System.arraycopy(expected, 0, truncated, 0, truncated.length);
  		expected = truncated;
  	}
  	return Arrays.equals(signature, expected);
  }
docs: Verifies the data (computes the secure hash and compares it to the input)
  @param signature The signature to compare against
  @param truncation_ok If true, the signature may be truncated; only the
  number of bytes in the provided signature are compared.
  @return true if the signature matches, false otherwise