import java.io.FileInputStream; import java.io.FileOutputStream; import java.util.zip.InflaterInputStream; public class Main { public static void main(String[] args) throws Exception { FileInputStream fin = new FileInputStream("a.dat"); InflaterInputStream iis = new InflaterInputStream(fin); FileOutputStream fout = new FileOutputStream("b.dat"); for (int c = iis.read(); c != -1; c = iis.read()) { fout.write(c); } fout.close(); } }