Class DfsOutputStream

    • Constructor Detail

      • DfsOutputStream

        public DfsOutputStream()
    • Method Detail

      • blockSize

        public int blockSize()
        Get the recommended alignment for writing.

        Starting a write at multiples of the blockSize is more efficient than starting a write at any other position. If 0 or -1 the channel does not have any specific block size recommendation.

        Channels should not recommend large block sizes. Sizes up to 1-4 MiB may be reasonable, but sizes above that may be horribly inefficient.

        recommended alignment size for randomly positioned reads. Does not need to be a power of 2.
      • read

        public abstract int read​(long position,
                                 ByteBuffer buf)
                          throws IOException
        Read back a portion of already written data.

        The writing position of the output stream is not affected by a read.

        position - offset to read from.
        buf - buffer to populate. Up to buf.remaining() bytes will be read from position.
        number of bytes actually read.
        IOException - reading is not supported, or the read cannot be performed due to DFS errors.