How to run java source files from other java files??

Question

hello all,
i need to run 3 to 4 .java files (first.java,second.java,third.java) from one file.
i tried the
Runtime.getRuntime().exec(cmd); but here cmd must be an exe file.
NOTE THAT i need to run the first.java file ,second.java file each time to generate their .class files(ie I NEED TO COMPILE THEM ALL TIMES AND THEN RUN THEM)
PLZ. help me if this can be done,
warm regards,
Vishal.

Answer 1

One way to do this is to put all your commands into a batch file (this is Windows?) try unix shell otherwise. Anyway here's an example .bat file called cmplrun.bat:
@echo off
javac -classpath . TestCase*.java
java -cp . TestCase01
java -cp . TestCase02
java -cp . TestCase03Then the Java pgm can look like this:
import java.io.*;
public class RunProcess {
  public static void main(String[] arg) {
    try {
      Process myProcess;
      myProcess = Runtime.getRuntime().exec("cmd /c cmplrun");
      String s = null;
      DataInputStream in = new DataInputStream(
                           new BufferedInputStream(
                               myProcess.getInputStream()));
      while ((s = in.readLine()) != null) {
        System.out.println(s);
      System.exit(0);
    catch (IOException e) {
      System.out.println("Exception: "+ e);
      System.exit(-1);
}Just one way to do this, all caveats apply and HTH;
~Bill