Class FileBackedOutputStream

    • Constructor Summary

      Constructors 
      Constructor Description
      FileBackedOutputStream​(int fileThreshold)
      Creates a new instance that uses the given file threshold, and does not reset the data when the ByteSource returned by asByteSource() is finalized.
      FileBackedOutputStream​(int fileThreshold, boolean resetOnFinalize)
      Creates a new instance that uses the given file threshold, and optionally resets the data when the ByteSource returned by asByteSource() is finalized.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      ByteSource asByteSource()
      Returns a readable ByteSource view of the data that has been written to this stream.
      void close()
      Closes this output stream and releases any system resources associated with this stream.
      void flush()
      Flushes this output stream and forces any buffered output bytes to be written out.
      void reset()
      Calls close() if not already closed, and then resets this object back to its initial state, for reuse.
      void write​(byte[] b)
      Writes b.length bytes from the specified byte array to this output stream.
      void write​(byte[] b, int off, int len)
      Writes len bytes from the specified byte array starting at offset off to this output stream.
      void write​(int b)
      Writes the specified byte to this output stream.
    • Constructor Detail

      • FileBackedOutputStream

        public FileBackedOutputStream​(int fileThreshold)
        Creates a new instance that uses the given file threshold, and does not reset the data when the ByteSource returned by asByteSource() is finalized.
        Parameters:
        fileThreshold - the number of bytes before the stream should switch to buffering to a file
      • FileBackedOutputStream

        public FileBackedOutputStream​(int fileThreshold,
                                      boolean resetOnFinalize)
        Creates a new instance that uses the given file threshold, and optionally resets the data when the ByteSource returned by asByteSource() is finalized.
        Parameters:
        fileThreshold - the number of bytes before the stream should switch to buffering to a file
        resetOnFinalize - if true, the reset() method will be called when the ByteSource returned by asByteSource() is finalized.
    • Method Detail

      • reset

        public void reset()
                   throws IOException
        Calls close() if not already closed, and then resets this object back to its initial state, for reuse. If data was buffered to a file, it will be deleted.
        Throws:
        IOException - if an I/O error occurred while deleting the file buffer
      • write

        public void write​(int b)
                   throws IOException
        Description copied from class: java.io.OutputStream
        Writes the specified byte to this output stream. The general contract for write is that one byte is written to the output stream. The byte to be written is the eight low-order bits of the argument b. The 24 high-order bits of b are ignored.

        Subclasses of OutputStream must provide an implementation for this method.

        Specified by:
        write in class OutputStream
        Parameters:
        b - the byte.
        Throws:
        IOException - if an I/O error occurs. In particular, an IOException may be thrown if the output stream has been closed.
      • write

        public void write​(byte[] b,
                          int off,
                          int len)
                   throws IOException
        Description copied from class: java.io.OutputStream
        Writes len bytes from the specified byte array starting at offset off to this output stream. The general contract for write(b, off, len) is that some of the bytes in the array b are written to the output stream in order; element b[off] is the first byte written and b[off+len-1] is the last byte written by this operation.

        The write method of OutputStream calls the write method of one argument on each of the bytes to be written out. Subclasses are encouraged to override this method and provide a more efficient implementation.

        If b is null, a NullPointerException is thrown.

        If off is negative, or len is negative, or off+len is greater than the length of the array b, then an IndexOutOfBoundsException is thrown.

        Overrides:
        write in class OutputStream
        Parameters:
        b - the data.
        off - the start offset in the data.
        len - the number of bytes to write.
        Throws:
        IOException - if an I/O error occurs. In particular, an IOException is thrown if the output stream is closed.
      • close

        public void close()
                   throws IOException
        Description copied from class: java.io.OutputStream
        Closes this output stream and releases any system resources associated with this stream. The general contract of close is that it closes the output stream. A closed stream cannot perform output operations and cannot be reopened.

        The close method of OutputStream does nothing.

        Specified by:
        close in interface AutoCloseable
        Specified by:
        close in interface Closeable
        Overrides:
        close in class OutputStream
        Throws:
        IOException - if an I/O error occurs.
      • flush

        public void flush()
                   throws IOException
        Description copied from class: java.io.OutputStream
        Flushes this output stream and forces any buffered output bytes to be written out. The general contract of flush is that calling it is an indication that, if any bytes previously written have been buffered by the implementation of the output stream, such bytes should immediately be written to their intended destination.

        If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.

        The flush method of OutputStream does nothing.

        Specified by:
        flush in interface Flushable
        Overrides:
        flush in class OutputStream
        Throws:
        IOException - if an I/O error occurs.