Java tutorial
import java.io.FileInputStream; import java.io.FileOutputStream; import java.util.zip.GZIPInputStream; public class Main { public static void main(String[] args) throws Exception { int sChunk = 8192; String zipname = "a.txt.gz"; String source = "a.txt"; FileInputStream in = new FileInputStream(zipname); GZIPInputStream zipin = new GZIPInputStream(in); byte[] buffer = new byte[sChunk]; FileOutputStream out = new FileOutputStream(source); int length; while ((length = zipin.read(buffer, 0, sChunk)) != -1) out.write(buffer, 0, length); out.close(); zipin.close(); } }