1. Description
2. Constructor Summary
3. Method Summary
4. Constructor Details
   1. OutputStream()
5. Method Details
   1. nullOutputStream()
   2. write(int)
   3. write(byte[])
   4. write(byte[], int, int)
   5. flush()
   6. close()

• Constructor Summary

  Constructors
  Constructor

  Description

  OutputStream()

  Constructor for subclasses to call.

• Method Summary

  All MethodsStatic MethodsInstance MethodsAbstract MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  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.

  static OutputStream

  nullOutputStream()

  Returns a new OutputStream which discards all bytes.

  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.

  abstract void

  write(int b)

  Writes the specified byte to this output stream.

  Methods declared in class Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  String

  toString()

  Returns a string representation of the object.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Constructor Details

  • OutputStream

    public OutputStream()

    Constructor for subclasses to call.

• Method Details

  • nullOutputStream

    public static OutputStream nullOutputStream()

    Returns a new OutputStream which discards all bytes. The returned stream is initially open. The stream is closed by calling the close() method. Subsequent calls to close() have no effect.

    While the stream is open, the write(int), write(byte[]), and write(byte[], int, int) methods do nothing. After the stream has been closed, these methods all throw IOException.

    The flush() method does nothing.

    Returns: an OutputStream which discards all bytes Since: 11

  • write

    public abstract void write(int b) throws IOException

    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.

    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) throws IOException

    Writes b.length bytes from the specified byte array to this output stream. The general contract for write(b) is that it should have exactly the same effect as the call write(b, 0, b.length).

    Parameters: b - the data. Throws: IOException - if an I/O error occurs. See Also:

    • write(byte[], int, int)

  • write

    public void write(byte[] b, int off, int len) throws IOException

    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.

    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.

    API Note: Subclasses are encouraged to override this method and provide a more efficient implementation. Implementation Requirements: The write method of OutputStream calls the write method of one argument on each of the bytes to be written out. 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. IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off

  • flush

    public void flush() throws IOException

    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.

    Specified by: flush in interface Flushable Implementation Requirements: The flush method of OutputStream does nothing. Throws: IOException - if an I/O error occurs.

  • close

    public void close() throws IOException

    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.

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Implementation Requirements: The close method of OutputStream does nothing. Throws: IOException - if an I/O error occurs.

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