(de)compressing files using NIO

Question

In the many examples online, files are (de)compressed in java using a coded buffer. With NIO, however, there is no need to choose a good buffer size. I found examples for fi

Answer 1

You can use the static utility methods in java.nio.channels.Channels to wrap streams in channels and vice versa.

E.g. to create a channel, from which you can read the uncompressed data from a gzip compressed file:

FileChannel fc = 
    new RandomAccessFile("input.gz", "r").getChannel();

ReadableByteChannel gzc = 
    Channels.newChannel(
            new GZIPInputStream(
                    Channels.newInputStream(fc)));

Answer 2

No, specialized ZIP channel does not exist yet... I think that you can do the following. Use NIO to read from any channel you want to Buffer. Then retrieve bytes you have just read from buffer to byte array, wrap the array using ByteArrayInputStream and pass it to ZIPInputStream.