ExecService.java

package com.cadrlife.devsearch.agent.service;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;

public class ExecService {
    private static final Logger LOG = LoggerFactory.getLogger(ExecService.class);

    public void gitClone(File pwd, String url) {
        execute(pwd, "git", "clone", url);
    }

	public void gitPull(File pwd) {
		execute(pwd, "git", "pull");
	}
	
	public void execute(File pwd, String...cmd) {
		String[] envp = {};
		exec(cmd, envp, pwd, logInfoAppendable(), logErrorAppendable());
	}
    
    private Appendable logErrorAppendable() {
        return new LoggingWriter(new LoggingWriter.LogHook() {
            @Override
            public void log(String msg) {
                LOG.error(msg);
            }
        });
    }

    private Appendable logInfoAppendable() {
        return new LoggingWriter(new LoggingWriter.LogHook() {
            @Override
            public void log(String msg) {
                LOG.info(msg);
            }
        });
    }

    /**
     * Executes a command and waits for the process to exit.
     * The process is queried every 100 milliseconds for completion.
     * stdoutWriter and stderrWriter can be the same object.
     *
     * @param cmd the command to be passed to {@link Runtime#exec(String[])}.
     * @param stdoutWriter buffer to which the process's stdout will be written. can be null.
     * @param stderrWriter buffer to which the process's stderr will be written. can be null.
     * @return the exit value of the process
     * @throws RuntimeException IOException and InterruptedException are wrapped in RuntimeException and thrown
     */
    private int exec(String[] cmd, String[] envp, File pwd, Appendable stdoutWriter, Appendable stderrWriter) {
        try {
            Process p = Runtime.getRuntime().exec(cmd, envp, pwd);
            InputStreamReader stdout = new InputStreamReader(p.getInputStream());
            InputStreamReader stderr = new InputStreamReader(p.getErrorStream());
            while (true) {
                int exitValue = -1;
                boolean done;
                try {
                    exitValue = p.exitValue();
                    done = true;
                } catch (IllegalThreadStateException e) {
                    done = false;
                }
                while (stdout.ready())
                    stdoutWriter.append((char)stdout.read());
                while (stderr.ready())
                    stderrWriter.append((char)stderr.read());
                if (done)
                    return exitValue;
                Thread.sleep(100);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        }
    }


}