code: public final void initSign(PrivateKey privateKey, SecureRandom random)
              throws InvalidKeyException {
          engineInitSign(privateKey, random);
          state = SIGN;
  
          // BEGIN Android-removed: this debugging mechanism is not supported in Android.
          /*
          if (!skipDebug && pdebug != null) {
              pdebug.println("Signature." + algorithm +
                  " signing algorithm from: " + this.provider.getName());
          }
          */
          // END Android-removed: this debugging mechanism is not supported in Android.
      }
docs: Initialize this object for signing. If this method is called
  again with a different argument, it negates the effect
  of this call.
  
  @param privateKey the private key of the identity whose signature
  is going to be generated.
  
  @param random the source of randomness for this signature.
  
  @exception InvalidKeyException if the key is invalid.