1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Field Details
   1. crc
   2. eos
   3. GZIP_MAGIC
6. Constructor Details
   1. GZIPInputStream(InputStream, int)
   2. GZIPInputStream(InputStream)
7. Method Details
   1. read(byte[], int, int)
   2. close()

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected CRC32

  crc

  CRC-32 for uncompressed data.

  protected boolean

  eos

  Indicates end of input stream.

  static final int

  GZIP_MAGIC

  GZIP header magic number.

  Fields declared in class InflaterInputStream

  buf, inf, len

  Modifier and Type

  Field

  Description

  protected byte[]

  buf

  Input buffer for decompression.

  protected Inflater

  inf

  Decompressor for this stream.

  protected int

  len

  The total number of bytes read into the input buffer.

  Fields declared in class FilterInputStream

  in

  Modifier and Type

  Field

  Description

  protected InputStream

  in

  The input stream to be filtered.

• Constructor Summary

  Constructors
  Constructor

  Description

  GZIPInputStream(InputStream in)

  Creates a new input stream with a default buffer size.

  GZIPInputStream(InputStream in, int size)

  Creates a new input stream with the specified buffer size.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  void

  close()

  Closes this input stream and releases any system resources associated with the stream.

  int

  read(byte[] buf, int off, int len)

  Reads uncompressed data into an array of bytes, returning the number of inflated bytes.

  Methods declared in class InflaterInputStream

  available, fill, mark, markSupported, read, reset, skip

  Modifier and Type

  Method

  Description

  int

  available()

  Returns 0 after EOF has been reached, otherwise always return 1.

  protected void

  fill()

  Fills input buffer with more data to decompress.

  void

  mark(int readlimit)

  Marks the current position in this input stream.

  boolean

  markSupported()

  Tests if this input stream supports the mark and reset methods.

  int

  read()

  Reads a byte of uncompressed data.

  void

  reset()

  Repositions this stream to the position at the time the mark method was last called on this input stream.

  long

  skip(long n)

  Skips specified number of bytes of uncompressed data.

  Methods declared in class FilterInputStream

  read

  Modifier and Type

  Method

  Description

  int

  read(byte[] b)

  Reads up to b.length bytes of data from this input stream into an array of bytes.

  Methods declared in class InputStream

  nullInputStream, readAllBytes, readNBytes, readNBytes, skipNBytes, transferTo

  Modifier and Type

  Method

  Description

  static InputStream

  nullInputStream()

  Returns a new InputStream that reads no bytes.

  byte[]

  readAllBytes()

  Reads all remaining bytes from the input stream.

  int

  readNBytes(byte[] b, int off, int len)

  Reads the requested number of bytes from the input stream into the given byte array.

  byte[]

  readNBytes(int len)

  Reads up to a specified number of bytes from the input stream.

  void

  skipNBytes(long n)

  Skips over and discards exactly n bytes of data from this input stream.

  long

  transferTo(OutputStream out)

  Reads all bytes from this input stream and writes the bytes to the given output stream in the order that they are read.

  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 for uncompressed data.

  • eos

    protected boolean eos

    Indicates end of input stream.

  • GZIP_MAGIC

    public static final int GZIP_MAGIC

    GZIP header magic number.

    See Also:

    • Constant Field Values

• Constructor Details

  • GZIPInputStream

    public GZIPInputStream(InputStream in, int size) throws IOException

    Creates a new input stream with the specified buffer size.

    Parameters: in - the input stream size - the input buffer size Throws: ZipException - if a GZIP format error has occurred or the compression method used is unsupported NullPointerException - if in is null IOException - if an I/O error has occurred IllegalArgumentException - if size <= 0

  • GZIPInputStream

    public GZIPInputStream(InputStream in) throws IOException

    Creates a new input stream with a default buffer size.

    Parameters: in - the input stream Throws: ZipException - if a GZIP format error has occurred or the compression method used is unsupported NullPointerException - if in is null IOException - if an I/O error has occurred

• Method Details

  • read

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

    Reads uncompressed data into an array of bytes, returning the number of inflated bytes. If len is not zero, the method will block until some input can be decompressed; otherwise, no bytes are read and 0 is returned.

    If this method returns a nonzero integer n then buf[off] through buf[off+n-1] contain the uncompressed data. The content of elements buf[off+n] through buf[off+len-1] is undefined, contrary to the specification of the InputStream superclass, so an implementation is free to modify these elements during the inflate operation. If this method returns -1 or throws an exception then the content of buf[off] through buf[off+len -1] is undefined.

    Overrides: read in class InflaterInputStream Parameters: buf - the buffer into which the data is read off - the start offset in the destination array buf len - the maximum number of bytes read Returns: the actual number of bytes inflated, or -1 if the end of the compressed input stream is reached Throws: NullPointerException - If buf is null. IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than buf.length - off ZipException - if the compressed input data is corrupt. IOException - if an I/O error has occurred. See Also:

    • FilterInputStream.in

  • close

    public void close() throws IOException

    Closes this input stream and releases any system resources associated with the stream.

    Specified by: close in interface AutoCloseable Specified by: close in interface Closeable Overrides: close in class InflaterInputStream Throws: IOException - if an I/O error has occurred See Also:

    • FilterInputStream.in

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