The question is vague on what you are trying to do and how (no example code etc.)
Below is an example which when run results in:
HelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHelloHello
Java can decompress the data which kdb+ compressed with .Q.gz without issue:
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.zip.*;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.lang.String;
import com.kx.c;
public class Main {
public static String decompress(final byte[] bytes) throws IOException {
if (bytes == null || bytes.length == 0) {
return "";
}
try (final GZIPInputStream ungzip = new GZIPInputStream(new ByteArrayInputStream(bytes))) {
final ByteArrayOutputStream out = new ByteArrayOutputStream();
final byte[] data = new byte[8192];
int nRead;
while ((nRead = ungzip.read(data)) != -1) {
out.write(data, 0, nRead);
}
return out.toString();
}
}
public static void main(String[] args) {
c c = null;
Object result = null;
byte[] bytes = null;
try {
c = new c("localhost", 5001);
String query="`byte$.Q.gz(9;400#\"Hello\")";
result = c.k(query);
bytes = ((byte[]) result);
System.out.println(decompress(bytes));
} catch (Exception e){
System.err.println(e.toString());
}
}
}