Module java.desktop

Class ImageInputStreamImpl

    • Field Detail

      • byteOrder

        protected ByteOrder byteOrder
        The byte order of the stream as an instance of the enumeration class java.nio.ByteOrder, where ByteOrder.BIG_ENDIAN indicates network byte order and ByteOrder.LITTLE_ENDIAN indicates the reverse order. By default, the value is ByteOrder.BIG_ENDIAN.
      • streamPos

        protected long streamPos
        The current read position within the stream. Subclasses are responsible for keeping this value current from any method they override that alters the read position.
      • bitOffset

        protected int bitOffset
        The current bit offset within the stream. Subclasses are responsible for keeping this value current from any method they override that alters the bit offset.
      • flushedPos

        protected long flushedPos
        The position prior to which data may be discarded. Seeking to a smaller position is not allowed. flushedPos will always be >= 0.
    • Constructor Detail

      • ImageInputStreamImpl

        public ImageInputStreamImpl()
        Constructs an ImageInputStreamImpl.
    • Method Detail

      • checkClosed

        protected final void checkClosed()
                                  throws IOException
        Throws an IOException if the stream has been closed. Subclasses may call this method from any of their methods that require the stream not to be closed.
        Throws:
        IOException - if the stream is closed.
      • read

        public abstract int read()
                          throws IOException
        Reads a single byte from the stream and returns it as an int between 0 and 255. If EOF is reached, -1 is returned.

        Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

        The bit offset within the stream must be reset to zero before the read occurs.

        Specified by:
        read in interface ImageInputStream
        Returns:
        the value of the next byte in the stream, or -1 if EOF is reached.
        Throws:
        IOException - if the stream has been closed.
      • read

        public int read​(byte[] b)
                 throws IOException
        A convenience method that calls read(b, 0, b.length).

        The bit offset within the stream is reset to zero before the read occurs.

        Specified by:
        read in interface ImageInputStream
        Parameters:
        b - an array of bytes to be written to.
        Returns:
        the number of bytes actually read, or -1 to indicate EOF.
        Throws:
        NullPointerException - if b is null.
        IOException - if an I/O error occurs.
      • read

        public abstract int read​(byte[] b,
                                 int off,
                                 int len)
                          throws IOException
        Reads up to len bytes from the stream, and stores them into b starting at index off. If no bytes can be read because the end of the stream has been reached, -1 is returned.

        The bit offset within the stream must be reset to zero before the read occurs.

        Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

        Specified by:
        read in interface ImageInputStream
        Parameters:
        b - an array of bytes to be written to.
        off - the starting position within b to write to.
        len - the maximum number of bytes to read.
        Returns:
        the number of bytes actually read, or -1 to indicate EOF.
        Throws:
        IndexOutOfBoundsException - if off is negative, len is negative, or off + len is greater than b.length.
        NullPointerException - if b is null.
        IOException - if an I/O error occurs.
      • length

        public long length()
        Returns -1L to indicate that the stream has unknown length. Subclasses must override this method to provide actual length information.
        Specified by:
        length in interface ImageInputStream
        Returns:
        -1L to indicate unknown length.
      • skipBytes

        public int skipBytes​(int n)
                      throws IOException
        Advances the current stream position by calling seek(getStreamPosition() + n).

        The bit offset is reset to zero.

        Specified by:
        skipBytes in interface DataInput
        Specified by:
        skipBytes in interface ImageInputStream
        Parameters:
        n - the number of bytes to seek forward.
        Returns:
        an int representing the number of bytes skipped.
        Throws:
        IOException - if getStreamPosition throws an IOException when computing either the starting or ending position.
      • skipBytes

        public long skipBytes​(long n)
                       throws IOException
        Advances the current stream position by calling seek(getStreamPosition() + n).

        The bit offset is reset to zero.

        Specified by:
        skipBytes in interface ImageInputStream
        Parameters:
        n - the number of bytes to seek forward.
        Returns:
        a long representing the number of bytes skipped.
        Throws:
        IOException - if getStreamPosition throws an IOException when computing either the starting or ending position.
      • mark

        public void mark()
        Pushes the current stream position onto a stack of marked positions.
        Specified by:
        mark in interface ImageInputStream
      • reset

        public void reset()
                   throws IOException
        Resets the current stream byte and bit positions from the stack of marked positions.

        An IOException will be thrown if the previous marked position lies in the discarded portion of the stream.

        Specified by:
        reset in interface ImageInputStream
        Throws:
        IOException - if an I/O error occurs.
      • finalize

        @Deprecated(since="9")
        protected void finalize()
                         throws Throwable
        Deprecated.
        The finalize method has been deprecated. Subclasses that override finalize in order to perform cleanup should be modified to use alternative cleanup mechanisms and to remove the overriding finalize method. When overriding the finalize method, its implementation must explicitly ensure that super.finalize() is invoked as described in Object.finalize(). See the specification for Object.finalize() for further information about migration options.
        Finalizes this object prior to garbage collection. The close method is called to close any open input source. This method should not be called from application code.
        Overrides:
        finalize in class Object
        Throws:
        Throwable - if an error occurs during superclass finalization.
        See Also:
        WeakReference, PhantomReference