Implements an input stream filter for compressing data in the “deflate” compression format.
Constructor and Description
- DeflaterInputStream(InputStream in) : Creates a new input stream with a default compressor and buffer size.
- DeflaterInputStream(InputStream in, Deflater defl) : Creates a new input stream with the specified compressor and a default buffer size.
- DeflaterInputStream(InputStream in, Deflater defl, int bufLen) :Creates a new input stream with the specified compressor and buffer size.
Methods:
-
int available() : Returns 0 after EOF has been reached, otherwise always return 1.
Syntax :public int available() throws IOException Parameters: n - number of bytes to be skipped Returns: the actual number of bytes skipped Throws: IOException -
void close() : Closes this input stream and its underlying input stream, discarding any pending uncompressed data.
Syntax :public void close() throws IOException Overrides: close in class FilterInputStream Throws: IOException -
void mark(int limit) : This operation is not supported.
Syntax :public void mark(int limit) Parameters: limit - maximum bytes that can be read before invalidating the position marker
-
boolean markSupported() : Always returns false because this input stream does not support the mark() and reset() methods.
Syntax :public boolean markSupported() Returns: false, always
-
int read() : Reads a single byte of compressed data from the input stream.
Syntax :public int read() throws IOException Returns: a single byte of compressed data, or -1 if the end of the uncompressed input stream is reached Throws: IOException -
int read(byte[] b, int off, int len) : Reads compressed data into a byte array.
Syntax :public int read(byte[] b, int off, int len) throws IOException Parameters: b - buffer into which the data is read off - starting offset of the data within b len - maximum number of compressed bytes to read into b Returns: the actual number of bytes read, or -1 if the end of the uncompressed input stream is reached Throws: IndexOutOfBoundsException IOException -
void reset() : This operation is not supported.
Syntax :public void reset() throws IOException Throws: IOException -
long skip(long n) : Skips over and discards data from the input stream.
Syntax :public long skip(long n) throws IOException Parameters: n - number of bytes to be skipped Returns: the actual number of bytes skipped Throws: IOException
Program:
//Java program to illustrate DeflaterInputStream class import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.zip.DeflaterInputStream;
class DeflaterInputStreamDemo
{ public static void main(String[] args) throws IOException
{
byte b[] = new byte[10];
for (byte i = 0; i <10 ; i++)
{
b[i] = i;
}
ByteArrayInputStream bin = new ByteArrayInputStream(b);
DeflaterInputStream din = new DeflaterInputStream(bin);
//illustrating markSupported() method
System.out.println(din.markSupported());
//illustrating skip() method
din.skip(1);
//illustrating available() method
System.out.println(din.available());
//illustrating read(byte[] b,int off,int len)
byte c[] = new byte[10];
din.read(c,0,9);
for (int i = 0; i < 9; i++)
{
System.out.print(c[i]);
}
while(din.available() == 1)
{
//Reads a single byte of compressed data
System.out.print(din.read());
}
System.out.println();
System.out.println(din.available());
// illustrating close() method
din.close();
}
} |
Output :
false 1 -1009996100981029710199231224400175046-1 0
The above output represents compressed data.
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