Java IO.pdf - Nguyen Dang Binh

Java I/O
to store the dictionary file, along with the compressed data, in an archive. Another possibility
is that programs that read and write many very similar files may always use the same
dictionary built into both the compression and decompression programs.
9.1.2.5 Inflate the data
Once setInput() has filled the input buffer with data, it is inflated through one of two
inflate() methods:
public int inflate(byte[] output) throws DataFormatException
public native synchronized int inflate(byte[] output, int offset, int
length)
throws DataFormatException
The first method fills the output array with the uncompressed data. The second fills the
specified subarray, beginning at offset and continuing for length bytes, with the
uncompressed data. The actual number of uncompressed bytes written into the array is
returned. If one of these methods returns 0, then you should check needsInput() to see if
you need to call setInput() again to insert more compressed input data:
public boolean needsInput()
When more data is needed, needsInput()returns true. At this point you call setInput()
again to feed in more compressed input data, then call inflate(), then repeat the process
until there is no more input data to be decompressed. If more data is not needed after
inflate() returns zero, this should mean that decompression is finished, and the
finished() method should return true:
public synchronized boolean finished()
The inflate() methods throw a java.util.zip.DataFormatException if they encounter
invalid data, generally indicating a corrupted input stream. This is a direct subclass of
java.lang.Exception, not an IOException.
9.1.2.6 Reset the inflater
This completes the sequence of method invocations required to decompress data. If you'd like
to use the same settings to decompress more data with the same Inflater object, you can
invoke its reset() method:
public native synchronized void reset()
Otherwise, you call end() to throw away any unprocessed input and free the resources used
by the native code:
public native synchronized void end()
The finalize() method calls end() before the inflater is garbage-collected, even if you
forget to invoke it explicitly:
protected void finalize()
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