Check out example codes for "runtime java examples". It will help you in understanding the concepts better.

Code Example 1

public static void main(String args[])throws IOException
{
    try
    {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        System.out.println("Enter your git remote url");//Accepting URL
        String u=br.readLine();
        URL url=new URL(u);
        //System.out.println("Enter your commit sentence");//Commit line
        String commit="make it better";
        System.out.println("Get ready for your code to be on github in few minutes..");
        String comd[]=new String[6];
        comd[0]="git init";
        comd[1]="git add .";
        comd[2]="git commit -m \""+commit+"\"";
        comd[3]="git remote add origin "+url;
        comd[4]="git push -u origin master";
        //comd[4]="git push -f origin master"; // Sometimes harmful to execute without user prompt
        for(int i=0;i<5;i++)
        {
            String cmd=comd[i];
            Runtime run = Runtime.getRuntime();
            Process pr = run.exec(cmd);
            pr.waitFor();
            BufferedReader buf = new BufferedReader(new InputStreamReader(pr.getInputStream()));
            String line = "";
            while ((line=buf.readLine())!=null) {
                System.out.println(line);
                //Error handling and force push prompts has to be handled
            }
        }
        System.out.println("Uploaded on github..");
    }catch(InterruptedException e){

    }
}

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