Module java.desktop

Class FileCacheImageInputStream

    • Constructor Detail

      • FileCacheImageInputStream

        public FileCacheImageInputStream​(InputStream stream,
                                         File cacheDir)
                                  throws IOException
        Constructs a FileCacheImageInputStream that will read from a given InputStream.

        A temporary file is used as a cache. If cacheDir is non-null and is a directory, the file will be created there. If it is null, the system-dependent default temporary-file directory will be used (see the documentation for File.createTempFile for details).

        Parameters:
        stream - an InputStream to read from.
        cacheDir - a File indicating where the cache file should be created, or null to use the system directory.
        Throws:
        IllegalArgumentException - if stream is null.
        IllegalArgumentException - if cacheDir is non-null but is not a directory.
        IOException - if a cache file cannot be created.
    • Method Detail

      • read

        public int read​()
                 throws IOException
        Description copied from class: ImageInputStreamImpl
        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
        Specified by:
        read in class ImageInputStreamImpl
        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,
                        int off,
                        int len)
                 throws IOException
        Description copied from class: ImageInputStreamImpl
        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
        Specified by:
        read in class ImageInputStreamImpl
        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:
        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 ImageInputStreamImpl
        Throws:
        Throwable - if an error occurs during superclass finalization.
        See Also:
        WeakReference, PhantomReference