Stirling-PDF/src/main/java/stirling/software/SPDF/utils/ProcessExecutor.java

package stirling.software.SPDF.utils;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;
public class ProcessExecutor {
	public static int runCommandWithOutputHandling(List<String> command) throws IOException, InterruptedException {
	    ProcessBuilder processBuilder = new ProcessBuilder(command);
	    Process process = processBuilder.start();

	    // Read the error stream and standard output stream concurrently
	    List<String> errorLines = new ArrayList<>();
	    List<String> outputLines = new ArrayList<>();

	    Thread errorReaderThread = new Thread(() -> {
	        try (BufferedReader errorReader = new BufferedReader(new InputStreamReader(process.getErrorStream(), StandardCharsets.UTF_8))) {
	            String line;
	            while ((line = errorReader.readLine()) != null) {
	                errorLines.add(line);
	            }
	        } catch (IOException e) {
	            e.printStackTrace();
	        }
	    });

	    Thread outputReaderThread = new Thread(() -> {
	        try (BufferedReader outputReader = new BufferedReader(new InputStreamReader(process.getInputStream(), StandardCharsets.UTF_8))) {
	            String line;
	            while ((line = outputReader.readLine()) != null) {
	                outputLines.add(line);
	            }
	        } catch (IOException e) {
	            e.printStackTrace();
	        }
	    });

	    errorReaderThread.start();
	    outputReaderThread.start();

	    // Wait for the conversion process to complete
	    int exitCode = process.waitFor();

	    // Wait for the reader threads to finish
	    errorReaderThread.join();
	    outputReaderThread.join();

	    if (outputLines.size() > 0) {
	        String outputMessage = String.join("\n", outputLines);
	        System.out.println("Command output:\n" + outputMessage);
	    }

	    if (errorLines.size() > 0) {
	        String errorMessage = String.join("\n", errorLines);
	        System.out.println("Command error output:\n" + errorMessage);
	        if (exitCode != 0) {
	            throw new IOException("Command process failed with exit code " + exitCode + ". Error message: " + errorMessage);
	        }
	    }

	    return exitCode;
	}
   		
	    		
}