Inflater
open class Inflater
| kotlin.Any | |
| ↳ | java.util.zip.Inflater |
This class provides support for general purpose decompression using the popular ZLIB compression library. The ZLIB compression library was initially developed as part of the PNG graphics standard and is not protected by patents. It is fully described in the specifications at the java.util.zip package description.
This class inflates sequences of ZLIB compressed bytes. The input byte sequence is provided in either byte array or byte buffer, via one of the setInput() methods. The output byte sequence is written to the output byte array or byte buffer passed to the deflate() methods.
The following code fragment demonstrates a trivial compression and decompression of a string using Deflater and Inflater.
try {
// Encode a String into bytes
String inputString = "blahblahblah\u20AC\u20AC";
byte[] input = inputString.getBytes("UTF-8");
// Compress the bytes
byte[] output = new byte[100];
Deflater compresser = new Deflater();
compresser.setInput(input);
compresser.finish();
int compressedDataLength = compresser.deflate(output);
// Decompress the bytes
Inflater decompresser = new Inflater();
decompresser.setInput(output, 0, compressedDataLength);
byte[] result = new byte[100];
int resultLength = decompresser.inflate(result);
decompresser.end();
// Decode the bytes into a String
String outputString = new String(result, 0, resultLength, "UTF-8");
} catch (java.io.UnsupportedEncodingException ex) {
// handle
} catch (java.util.zip.DataFormatException ex) {
// handle
}
Summary
| Public constructors | |
|---|---|
|
Creates a new decompressor. |
|
Inflater()Creates a new decompressor. |
|
| Public methods | |
|---|---|
| open Unit |
end()Closes the decompressor and discards any unprocessed input. |
| open Boolean |
finished()Returns true if the end of the compressed data stream has been reached. |
| open Int |
getAdler()Returns the ADLER-32 value of the uncompressed data. |
| open Long |
Returns the total number of compressed bytes input so far. |
| open Long |
Returns the total number of uncompressed bytes output so far. |
| open Int |
Returns the total number of bytes remaining in the input buffer. |
| open Int |
Returns the total number of compressed bytes input so far. |
| open Int |
Returns the total number of uncompressed bytes output so far. |
| open Int |
Uncompresses bytes into specified buffer. |
| open Int |
Uncompresses bytes into specified buffer. |
| open Int |
inflate(output: ByteBuffer!)Uncompresses bytes into specified buffer. |
| open Boolean |
Returns true if a preset dictionary is needed for decompression. |
| open Boolean |
Returns true if no data remains in the input buffer. |
| open Unit |
reset()Resets inflater so that a new set of input data can be processed. |
| open Unit |
setDictionary(dictionary: ByteArray!, off: Int, len: Int)Sets the preset dictionary to the given array of bytes. |
| open Unit |
setDictionary(dictionary: ByteArray!)Sets the preset dictionary to the given array of bytes. |
| open Unit |
setDictionary(dictionary: ByteBuffer!)Sets the preset dictionary to the bytes in the given buffer. |
| open Unit |
Sets input data for decompression. |
| open Unit |
Sets input data for decompression. |
| open Unit |
setInput(input: ByteBuffer!)Sets input data for decompression. |
Public constructors
Inflater
Inflater(nowrap: Boolean)
Creates a new decompressor. If the parameter 'nowrap' is true then the ZLIB header and checksum fields will not be used. This provides compatibility with the compression format used by both GZIP and PKZIP.
Note: When using the 'nowrap' option it is also necessary to provide an extra "dummy" byte as input. This is required by the ZLIB native library in order to support certain optimizations.
| Parameters | |
|---|---|
nowrap |
Boolean: if true then support GZIP compatible compression |
Public methods
end
open fun end(): Unit
Closes the decompressor and discards any unprocessed input. This method should be called when the decompressor is no longer being used. Once this method is called, the behavior of the Inflater object is undefined.
finished
open fun finished(): Boolean
Returns true if the end of the compressed data stream has been reached.
| Return | |
|---|---|
Boolean |
true if the end of the compressed data stream has been reached |
getAdler
open fun getAdler(): Int
Returns the ADLER-32 value of the uncompressed data.
| Return | |
|---|---|
Int |
the ADLER-32 value of the uncompressed data |
getBytesRead
open fun getBytesRead(): Long
Returns the total number of compressed bytes input so far.
| Return | |
|---|---|
Long |
the total (non-negative) number of compressed bytes input so far |
getBytesWritten
open fun getBytesWritten(): Long
Returns the total number of uncompressed bytes output so far.
| Return | |
|---|---|
Long |
the total (non-negative) number of uncompressed bytes output so far |
getRemaining
open fun getRemaining(): Int
Returns the total number of bytes remaining in the input buffer. This can be used to find out what bytes still remain in the input buffer after decompression has finished.
| Return | |
|---|---|
Int |
the total number of bytes remaining in the input buffer |
getTotalIn
open fun getTotalIn(): Int
Returns the total number of compressed bytes input so far.
Since the number of bytes may be greater than Integer.MAX_VALUE, the getBytesRead() method is now the preferred means of obtaining this information.
| Return | |
|---|---|
Int |
the total number of compressed bytes input so far |
getTotalOut
open fun getTotalOut(): Int
Returns the total number of uncompressed bytes output so far.
Since the number of bytes may be greater than Integer.MAX_VALUE, the getBytesWritten() method is now the preferred means of obtaining this information.
| Return | |
|---|---|
Int |
the total number of uncompressed bytes output so far |
inflate
open fun inflate(
output: ByteArray!,
off: Int,
len: Int
): Int
Uncompresses bytes into specified buffer. Returns actual number of bytes uncompressed. A return value of 0 indicates that needsInput() or needsDictionary() should be called in order to determine if more input data or a preset dictionary is required. In the latter case, getAdler() can be used to get the Adler-32 value of the dictionary required.
If the setInput(java.nio.ByteBuffer) method was called to provide a buffer for input, the input buffer's position will be advanced by the number of bytes consumed by this operation, even in the event that a DataFormatException is thrown.
The remaining byte count will be reduced by the number of consumed input bytes. If the setInput(java.nio.ByteBuffer) method was called to provide a buffer for input, the input buffer's position will be advanced the number of consumed bytes.
These byte totals, as well as the total bytes read and the total bytes written values, will be updated even in the event that a DataFormatException is thrown to reflect the amount of data consumed and produced before the exception occurred.
| Parameters | |
|---|---|
output |
ByteArray!: the buffer for the uncompressed data |
off |
Int: the start offset of the data |
len |
Int: the maximum number of uncompressed bytes |
| Return | |
|---|---|
Int |
the actual number of uncompressed bytes |
| Exceptions | |
|---|---|
java.util.zip.DataFormatException |
if the compressed data format is invalid |
inflate
open fun inflate(output: ByteArray!): Int
Uncompresses bytes into specified buffer. Returns actual number of bytes uncompressed. A return value of 0 indicates that needsInput() or needsDictionary() should be called in order to determine if more input data or a preset dictionary is required. In the latter case, getAdler() can be used to get the Adler-32 value of the dictionary required.
The remaining byte count will be reduced by the number of consumed input bytes. If the setInput(java.nio.ByteBuffer) method was called to provide a buffer for input, the input buffer's position will be advanced the number of consumed bytes.
These byte totals, as well as the total bytes read and the total bytes written values, will be updated even in the event that a DataFormatException is thrown to reflect the amount of data consumed and produced before the exception occurred.
| Parameters | |
|---|---|
output |
ByteArray!: the buffer for the uncompressed data |
| Return | |
|---|---|
Int |
the actual number of uncompressed bytes |
| Exceptions | |
|---|---|
java.util.zip.DataFormatException |
if the compressed data format is invalid |
inflate
open fun inflate(output: ByteBuffer!): Int
Uncompresses bytes into specified buffer. Returns actual number of bytes uncompressed. A return value of 0 indicates that needsInput() or needsDictionary() should be called in order to determine if more input data or a preset dictionary is required. In the latter case, getAdler() can be used to get the Adler-32 value of the dictionary required.
On success, the position of the given output byte buffer will be advanced by as many bytes as were produced by the operation, which is equal to the number returned by this method. Note that the position of the output buffer will be advanced even in the event that a DataFormatException is thrown.
The remaining byte count will be reduced by the number of consumed input bytes. If the setInput(java.nio.ByteBuffer) method was called to provide a buffer for input, the input buffer's position will be advanced the number of consumed bytes.
These byte totals, as well as the total bytes read and the total bytes written values, will be updated even in the event that a DataFormatException is thrown to reflect the amount of data consumed and produced before the exception occurred.
| Parameters | |
|---|---|
output |
ByteBuffer!: the buffer for the uncompressed data |
| Return | |
|---|---|
Int |
the actual number of uncompressed bytes |
| Exceptions | |
|---|---|
java.util.zip.DataFormatException |
if the compressed data format is invalid |
java.nio.ReadOnlyBufferException |
if the given output buffer is read-only |
needsDictionary
open fun needsDictionary(): Boolean
Returns true if a preset dictionary is needed for decompression.
| Return | |
|---|---|
Boolean |
true if a preset dictionary is needed for decompression |
See Also
needsInput
open fun needsInput(): Boolean
Returns true if no data remains in the input buffer. This can be used to determine if one of the setInput() methods should be called in order to provide more input.
| Return | |
|---|---|
Boolean |
true if no data remains in the input buffer |
reset
open fun reset(): Unit
Resets inflater so that a new set of input data can be processed.
setDictionary
open fun setDictionary(
dictionary: ByteArray!,
off: Int,
len: Int
): Unit
Sets the preset dictionary to the given array of bytes. Should be called when inflate() returns 0 and needsDictionary() returns true indicating that a preset dictionary is required. The method getAdler() can be used to get the Adler-32 value of the dictionary needed.
| Parameters | |
|---|---|
dictionary |
ByteArray!: the dictionary data bytes |
off |
Int: the start offset of the data |
len |
Int: the length of the data |
setDictionary
open fun setDictionary(dictionary: ByteArray!): Unit
Sets the preset dictionary to the given array of bytes. Should be called when inflate() returns 0 and needsDictionary() returns true indicating that a preset dictionary is required. The method getAdler() can be used to get the Adler-32 value of the dictionary needed.
| Parameters | |
|---|---|
dictionary |
ByteArray!: the dictionary data bytes |
setDictionary
open fun setDictionary(dictionary: ByteBuffer!): Unit
Sets the preset dictionary to the bytes in the given buffer. Should be called when inflate() returns 0 and needsDictionary() returns true indicating that a preset dictionary is required. The method getAdler() can be used to get the Adler-32 value of the dictionary needed.
The bytes in given byte buffer will be fully consumed by this method. On return, its position will equal its limit.
| Parameters | |
|---|---|
dictionary |
ByteBuffer!: the dictionary data bytes |
setInput
open fun setInput(
input: ByteArray!,
off: Int,
len: Int
): Unit
Sets input data for decompression.
One of the setInput() methods should be called whenever needsInput() returns true indicating that more input data is required.
| Parameters | |
|---|---|
input |
ByteArray!: the input data bytes |
off |
Int: the start offset of the input data |
len |
Int: the length of the input data |
See Also
setInput
open fun setInput(input: ByteArray!): Unit
Sets input data for decompression.
One of the setInput() methods should be called whenever needsInput() returns true indicating that more input data is required.
| Parameters | |
|---|---|
input |
ByteArray!: the input data bytes |
See Also
setInput
open fun setInput(input: ByteBuffer!): Unit
Sets input data for decompression.
One of the setInput() methods should be called whenever needsInput() returns true indicating that more input data is required.
The given buffer's position will be advanced as inflate operations are performed, up to the buffer's limit. The input buffer may be modified (refilled) between inflate operations; doing so is equivalent to creating a new buffer and setting it with this method.
Modifying the input buffer's contents, position, or limit concurrently with an inflate operation will result in undefined behavior, which may include incorrect operation results or operation failure.
| Parameters | |
|---|---|
input |
ByteBuffer!: the input data bytes |
See Also