On executing batch file capture command prompt logs and save a backup of those logs in file using Java

Question

To print the logs in file I used the below code,, but I not able to print "System.out.println" statement which exists in batch file code.

    Runtime runtime = Runtime.getRuntime();
    Process p1 = runtime.exec("C:\\Users\\mf11131\\Desktop\\Batch\\SimpleBatch.bat");
    java.io.InputStream is = (java.io.InputStream) p1.getInputStream();
    File logfile = new File("C:\\logs\\Logfile.txt");
    FileOutputStream fop = new FileOutputStream(logfile);
    int i = 0;
    while((i = is.read()) != -1)
    {
        fop.write((char)i);
    }

Below is the simple code of batch file.

class abc
{
   public static void main(String args[])
   {
     int count=0;
     for(int i=0;i<10;i++)
     {
        System.out.println("hi hello"+count);
     }
   }
}

I need output like below command prompt logs

My current output is

Answer 1

If you want to get all of the output into a file you should use stream redirection like this

byBatFile.bat > logFile. 

This will cause all the output to be stored into logFile .

I have my doubts about possibility to get stdio streams of invoked applications inside batch script. I think that IO is separated in manners you would like to use it.

On the other hand, your batch script "spawns" new processes on every command. You could try to call those processes insteed of spawning new ones like this

call javac abc.java
call java abc

Answer 2

I found the solution for this as I done a mistake of pointing directory to Java class directory while creating a Batch file. So only Java (System.out.println) statements are not printing.