missing command output

 // Run apt update command
            Process updateProcess = Runtime.getRuntime().exec("apt update");
            updateProcess.waitFor();
            // Read the output of apt update
            BufferedReader updateReader = new BufferedReader(new InputStreamReader(updateProcess.getInputStream()));
            String updateLine;
            boolean upToDate = false;

            // Read all the lines of output
            StringBuilder updateOutput = new StringBuilder();
            while ((updateLine = updateReader.readLine()) != null) {
                updateOutput.append(updateLine).append("\n");
                System.out.println("Proccess Reader: " + updateLine);
            }

            // Check if all packages are up to date
            if (updateOutput.toString().contains("All packages are up to date.")) {
                upToDate = true;
            }