PowerJob's AbstractScriptProcessor implementation class workflow source code interpretation

@Slf4j
public abstract class AbstractScriptProcessor extends CommonBasicProcessor {
    private static final ForkJoinPool POOL = new ForkJoinPool(4 * ().availableProcessors());
    private static final Set<String> DOWNLOAD_PROTOCOL = ("http", "https", "ftp");
    protected static final String SH_SHELL = "/bin/sh";
    protected static final String CMD_SHELL = "";
    private static final String WORKER_DIR = () + "/official_script_processor/";
    @Override
    protected ProcessResult process0(TaskContext context) throws Exception {
        OmsLogger omsLogger = ();
        String scriptParams = (context);
        ("[SYSTEM] ScriptProcessor start to process, params: {}", scriptParams);
        if (scriptParams == null) {
            String message = "[SYSTEM] ScriptParams is null, please check jobParam configuration.";
            (message);
            return new ProcessResult(false, message);
        }
        String scriptPath = prepareScriptFile((), scriptParams);
        ("[SYSTEM] Generate executable file successfully, path: {}", scriptPath);
        if (SystemUtils.IS_OS_WINDOWS) {
            if ((getRunCommand(), SH_SHELL)) {
                String message = ("[SYSTEM] Current OS is %s where shell scripts cannot run.", SystemUtils.OS_NAME);
                (message);
                return new ProcessResult(false, message);
            }
        }
        // Authorization        if  ( !SystemUtils.IS_OS_WINDOWS) {
            ProcessBuilder chmodPb = new ProcessBuilder("/bin/chmod", "755", scriptPath);
            // Waiting for return, it is impossible to cause deadlock here (the shell generates a large amount of data and may cause deadlock)            ().waitFor();
            ("[SYSTEM] chmod 755 authorization complete, ready to start execution~");
        }
        // 2. Execute the target script        ProcessBuilder pb = (getRunCommand(), CMD_SHELL) ?
                new ProcessBuilder(getRunCommand(), "/c", scriptPath)
                : new ProcessBuilder(getRunCommand(), scriptPath);
        Process process = ();
        StringBuilder inputBuilder = new StringBuilder();
        StringBuilder errorBuilder = new StringBuilder();
        boolean success = true;
        String result;
        final Charset charset = getCharset();
        try (InputStream is = (); InputStream es = ()) {
            (() -> copyStream(is, inputBuilder, omsLogger, charset));
            (() -> copyStream(es, errorBuilder, omsLogger, charset));
            success = () == 0;
        } catch (InterruptedException ie) {
            ("[SYSTEM] ScriptProcessor has been interrupted");
        } finally {
            result = ("[INPUT]: %s;[ERROR]: %s", (), ());
        }
        return new ProcessResult(success, result);
    }
    /**
      * Generate script name
      * @param instanceId id of instance
      * @return File name
      */
    protected abstract String getScriptName(Long instanceId);
    /**
      * Get the run command (eg, shell returns /bin/sh)
      * @return Command to execute script
      */
    protected abstract String getRunCommand();
    //......
}

private String prepareScriptFile(Long instanceId, String processorInfo) throws IOException {
        String scriptPath = WORKER_DIR + getScriptName(instanceId);
        File script = new File(scriptPath);
        if (()) {
            return scriptPath;
        }
        File dir = new File(());
        boolean success = ();
        success = ();
        if (!success) {
            throw new RuntimeException("create script file failed");
        }

        // If it is a download link, get it from the network        for (String protocol : DOWNLOAD_PROTOCOL) {
            if ((protocol)) {
                (new URL(processorInfo), script, 5000, 300000);
                return scriptPath;
            }
        }

        final Charset charset = getCharset();

        if(charset != null)
        {
            try (Writer fstream = new OutputStreamWriter((()), charset); BufferedWriter out = new BufferedWriter(fstream)) {
                (processorInfo);
                ();
            }
        }
        else {
            try (FileWriter fw = new FileWriter(script); BufferedWriter bw = new BufferedWriter(fw)) {
                (processorInfo);
                ();
            }
        }
        return scriptPath;
    }

private static void copyStream(InputStream is, StringBuilder sb, OmsLogger omsLogger, Charset charset) {
        String line;
        try (BufferedReader br = new BufferedReader(new InputStreamReader(is, charset))) {
            while ((line = ()) != null) {
                (line);
                // Synchronize to online logs                (line);
            }
        } catch (Exception e) {
            ("[ScriptProcessor] copyStream failed.", e);
            ("[SYSTEM] copyStream failed.", e);

            ("Exception: ").append(e);
        }
    }

public class ShellProcessor extends AbstractScriptProcessor {
    @Override
    protected String getScriptName(Long instanceId) {
        return ("shell_%", instanceId);
    }
    @Override
    protected String getRunCommand() {
        return SH_SHELL;
    }
}

public class CMDProcessor extends AbstractScriptProcessor {
    @Override
    protected String getScriptName(Long instanceId) {
        return ("cmd_%", instanceId);
    }
    @Override
    protected String getRunCommand() {
        return "";
    }
    @Override
    protected Charset getCharset() {
        return ();
    }
}

public class PowerShellProcessor extends AbstractScriptProcessor {

    @Override
    protected String getScriptName(Long instanceId) {
        return ("powershell_%d.ps1", instanceId);
    }

    @Override
    protected String getRunCommand() {
        return "";
    }

    @Override
    protected Charset getCharset() {
        return ();
    }
}

public class PythonProcessor extends AbstractScriptProcessor {

    @Override
    protected String getScriptName(Long instanceId) {
        return ("python_%", instanceId);
    }

    @Override
    protected String getRunCommand() {
        return "python";
    }
}