1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Field Details
   1. crc
6. Constructor Details
   1. GZIPOutputStream(OutputStream, int)
   2. GZIPOutputStream(OutputStream, int, boolean)
   3. GZIPOutputStream(OutputStream)
   4. GZIPOutputStream(OutputStream, boolean)
7. Method Details
   1. write(byte[], int, int)
   2. finish()

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected CRC32

  crc

  CRC-32 of uncompressed data.

  Fields declared in class DeflaterOutputStream

  buf, def

  Modifier and Type

  Field

  Description

  protected byte[]

  buf

  Output buffer for writing compressed data.

  protected Deflater

  def

  Compressor for this stream.

  Fields declared in class FilterOutputStream

  out

  Modifier and Type

  Field

  Description

  protected OutputStream

  out

  The underlying output stream to be filtered.

• Constructor Summary

  Constructors
  Constructor

  Description

  GZIPOutputStream(OutputStream out)

  Creates a new output stream with a default buffer size.

  GZIPOutputStream(OutputStream out, boolean syncFlush)

  Creates a new output stream with a default buffer size and the specified flush mode.

  GZIPOutputStream(OutputStream out, int size)

  Creates a new output stream with the specified buffer size.

  GZIPOutputStream(OutputStream out, int size, boolean syncFlush)

  Creates a new output stream with the specified buffer size and flush mode.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  void

  finish()

  Finishes writing compressed data to the output stream without closing the underlying stream.

  void

  write(byte[] buf, int off, int len)

  Writes array of bytes to the compressed output stream.

  Methods declared in class DeflaterOutputStream

  close, deflate, flush, write

  Modifier and Type

  Method

  Description

  void

  close()

  Writes remaining compressed data to the output stream and closes the underlying stream.

  protected void

  deflate()

  Writes next block of compressed data to the output stream.

  void

  flush()

  Flushes the compressed output stream.

  void

  write(int b)

  Writes a byte to the compressed output stream.

  Methods declared in class FilterOutputStream

  write

  Modifier and Type

  Method

  Description

  void

  write(byte[] b)

  Writes b.length bytes to this output stream.

  Methods declared in class OutputStream

  nullOutputStream

  Modifier and Type

  Method

  Description

  static OutputStream

  nullOutputStream()

  Returns a new OutputStream which discards all bytes.

  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.

• Field Details

  • crc

    protected CRC32 crc

    CRC-32 of uncompressed data.

• Constructor Details

  • GZIPOutputStream

    public GZIPOutputStream(OutputStream out, int size) throws IOException

    Creates a new output stream with the specified buffer size.

    The new output stream instance is created as if by invoking the 3-argument constructor GZIPOutputStream(out, size, false).

    Parameters: out - the output stream size - the output buffer size Throws: IOException - If an I/O error has occurred. IllegalArgumentException - if size <= 0

  • GZIPOutputStream

    public GZIPOutputStream(OutputStream out, int size, boolean syncFlush) throws IOException

    Creates a new output stream with the specified buffer size and flush mode.

    Parameters: out - the output stream size - the output buffer size syncFlush - if true invocation of the inherited flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream Throws: IOException - If an I/O error has occurred. IllegalArgumentException - if size <= 0 Since: 1.7

  • GZIPOutputStream

    public GZIPOutputStream(OutputStream out) throws IOException

    Creates a new output stream with a default buffer size.

    The new output stream instance is created as if by invoking the 2-argument constructor GZIPOutputStream(out, false).

    Parameters: out - the output stream Throws: IOException - If an I/O error has occurred.

  • GZIPOutputStream

    public GZIPOutputStream(OutputStream out, boolean syncFlush) throws IOException

    Creates a new output stream with a default buffer size and the specified flush mode.

    Parameters: out - the output stream syncFlush - if true invocation of the inherited flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream Throws: IOException - If an I/O error has occurred. Since: 1.7

• Method Details

  • write

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

    Writes array of bytes to the compressed output stream. This method will block until all the bytes are written.

    Overrides: write in class DeflaterOutputStream Parameters: buf - the data to be written off - the start offset of the data len - the length of the data Throws: IOException - If an I/O error has occurred. See Also:

    • FilterOutputStream.write(int)

  • finish

    public void finish() throws IOException

    Finishes writing compressed data to the output stream without closing the underlying stream. Use this method when applying multiple filters in succession to the same output stream.

    Overrides: finish in class DeflaterOutputStream Throws: IOException - if an I/O error has occurred

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