ZlibDecompressor (Apache Hadoop Common 3.4.1.300-dep-1001 API)

java.lang.Object
- org.apache.hadoop.io.compress.zlib.ZlibDecompressor

All Implemented Interfaces:

Decompressor

Direct Known Subclasses:

ZlibDecompressor.ZlibDirectDecompressor
```
public class ZlibDecompressor
extends java.lang.Object
implements Decompressor
```
A Decompressor based on the popular zlib compression algorithm. http://www.zlib.net/

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`ZlibDecompressor.CompressionHeader`	The headers to detect from compressed data.
`static class`	`ZlibDecompressor.ZlibDirectDecompressor`

Constructor Summary

Constructors
Constructor	Description
`ZlibDecompressor()`
`ZlibDecompressor(ZlibDecompressor.CompressionHeader header, int directBufferSize)`	Creates a new decompressor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`decompress(byte[] b, int off, int len)`	Fills specified buffer with uncompressed data.
`void`	`end()`	Closes the decompressor and discards any unprocessed input.
`protected void`	`finalize()`
`boolean`	`finished()`	Returns `true` if the end of the decompressed data output stream has been reached.
`long`	`getBytesRead()`	Returns the total number of compressed bytes input so far.
`long`	`getBytesWritten()`	Returns the total number of uncompressed bytes output so far.
`int`	`getRemaining()`	Returns the number of bytes remaining in the input buffers; normally called when finished() is true to determine amount of post-gzip-stream data.
`boolean`	`needsDictionary()`	Returns `true` if a preset dictionary is needed for decompression.
`boolean`	`needsInput()`	Returns `true` if the input data buffer is empty and `Decompressor.setInput(byte[], int, int)` should be called to provide more input.
`void`	`reset()`	Resets everything including the input buffers (user and direct).
`void`	`setDictionary(byte[] b, int off, int len)`	Sets preset dictionary for compression.
`void`	`setInput(byte[] b, int off, int len)`	Sets input data for decompression.

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ZlibDecompressor
```
public ZlibDecompressor(ZlibDecompressor.CompressionHeader header,
                        int directBufferSize)
```
    Creates a new decompressor.
    
    Parameters:
    
    header - header.
    
    directBufferSize - directBufferSize.
  - ZlibDecompressor
```
public ZlibDecompressor()
```
- Method Detail
  - setInput
```
public void setInput(byte[] b,
                     int off,
                     int len)
```
    Description copied from interface: Decompressor
    
    Sets input data for decompression. This should be called if and only if Decompressor.needsInput() returns true indicating that more input data is required. (Both native and non-native versions of various Decompressors require that the data passed in via b[] remain unmodified until the caller is explicitly notified--via Decompressor.needsInput()--that the buffer may be safely modified. With this requirement, an extra buffer-copy can be avoided.)
    
    Specified by:
    
    setInput in interface Decompressor
    
    Parameters:
    
    b - Input data
    
    off - Start offset
    
    len - Length
  - setDictionary
```
public void setDictionary(byte[] b,
                          int off,
                          int len)
```
    Description copied from interface: Decompressor
    
    Sets preset dictionary for compression. A preset dictionary is used when the history buffer can be predetermined.
    
    Specified by:
    
    setDictionary in interface Decompressor
    
    Parameters:
    
    b - Dictionary data bytes
    
    off - Start offset
    
    len - Length
  - needsInput
```
public boolean needsInput()
```
    Description copied from interface: Decompressor
    
    Returns true if the input data buffer is empty and Decompressor.setInput(byte[], int, int) should be called to provide more input.
    
    Specified by:
    
    needsInput in interface Decompressor
    
    Returns:
    
    true if the input data buffer is empty and Decompressor.setInput(byte[], int, int) should be called in order to provide more input.
  - needsDictionary
```
public boolean needsDictionary()
```
    Description copied from interface: Decompressor
    
    Returns true if a preset dictionary is needed for decompression.
    
    Specified by:
    
    needsDictionary in interface Decompressor
    
    Returns:
    
    true if a preset dictionary is needed for decompression
  - finished
```
public boolean finished()
```
    Description copied from interface: Decompressor
    
    Returns true if the end of the decompressed data output stream has been reached. Indicates a concatenated data stream when finished() returns true and Decompressor.getRemaining() returns a positive value. finished() will be reset with the Decompressor.reset() method.
    
    Specified by:
    
    finished in interface Decompressor
    
    Returns:
    
    true if the end of the decompressed data output stream has been reached.
  - decompress
```
public int decompress(byte[] b,
                      int off,
                      int len)
               throws java.io.IOException
```
    Description copied from interface: Decompressor
    
    Fills specified buffer with uncompressed data. Returns actual number of bytes of uncompressed data. A return value of 0 indicates that Decompressor.needsInput() should be called in order to determine if more input data is required.
    
    Specified by:
    
    decompress in interface Decompressor
    
    Parameters:
    
    b - Buffer for the uncompressed data
    
    off - Start offset of the data
    
    len - Size of the buffer
    
    Returns:
    
    The actual number of bytes of uncompressed data.
    
    Throws:
    
    java.io.IOException - raised on errors performing I/O.
  - getBytesWritten
```
public long getBytesWritten()
```
    Returns the total number of uncompressed bytes output so far.
    
    Returns:
    
    the total (non-negative) number of uncompressed bytes output so far
  - getBytesRead
```
public long getBytesRead()
```
    Returns the total number of compressed bytes input so far.
    
    Returns:
    
    the total (non-negative) number of compressed bytes input so far
  - getRemaining
```
public int getRemaining()
```
    Returns the number of bytes remaining in the input buffers; normally called when finished() is true to determine amount of post-gzip-stream data.
    
    Specified by:
    
    getRemaining in interface Decompressor
    
    Returns:
    
    the total (non-negative) number of unprocessed bytes in input
  - reset
```
public void reset()
```
    Resets everything including the input buffers (user and direct).
    
    Specified by:
    
    reset in interface Decompressor
  - end
```
public void end()
```
    Description copied from interface: Decompressor
    
    Closes the decompressor and discards any unprocessed input.
    
    Specified by:
    
    end in interface Decompressor
  - finalize
```
protected void finalize()
```
    Overrides:
    
    finalize in class java.lang.Object

Class ZlibDecompressor

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ZlibDecompressor

ZlibDecompressor

Method Detail

setInput

setDictionary

needsInput

needsDictionary

finished

decompress

getBytesWritten

getBytesRead

getRemaining

reset

end

finalize