Interface Padding


  • public interface Padding
    Padding interface. This interface is implemented by general-purpose padding schemes, such as the one described in PKCS#5.
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      int pad​(byte[] in, int off, int len)
      Performs padding for the given data input.
      int padLength​(int len)
      Determines how long the padding will be for a given input length.
      void padWithLen​(byte[] in, int off, int len)
      Adds the given number of padding bytes to the data input.
      int unpad​(byte[] in, int off, int len)
      Returns the index where padding starts.
    • Method Detail

      • pad

        int pad​(byte[] in,
                int off,
                int len)
         throws javax.crypto.ShortBufferException
        Performs padding for the given data input. The padding bytes are appended to the data input.
        Parameters:
        in - the input buffer with the data to pad
        off - the offset in in where the data to pad starts
        len - the length of the data to pad
        Returns:
        the number of padding bytes appended
        Throws:
        javax.crypto.ShortBufferException - if in is too small to hold the padding bytes
      • padWithLen

        void padWithLen​(byte[] in,
                        int off,
                        int len)
                 throws javax.crypto.ShortBufferException
        Adds the given number of padding bytes to the data input. The value of the padding bytes is determined by the specific padding mechanism that implements this interface.
        Parameters:
        in - the input buffer with the data to pad
        off - the offset in in where the padding bytes are appended
        len - the number of padding bytes to add
        Throws:
        javax.crypto.ShortBufferException - if in is too small to hold the padding bytes
      • unpad

        int unpad​(byte[] in,
                  int off,
                  int len)
        Returns the index where padding starts.

        Given a buffer with data and their padding, this method returns the index where the padding starts.

        Parameters:
        in - the buffer with the data and their padding
        off - the offset in in where the data starts
        len - the length of the data and their padding
        Returns:
        the index where the padding starts, or -1 if the input is not properly padded
      • padLength

        int padLength​(int len)
        Determines how long the padding will be for a given input length.
        Parameters:
        len - the length of the data to pad
        Returns:
        the length of the padding