Compile and Run a java program in another java program not working

I have 2 classes Tester.java and Main.java, I want to run Main.java from Tester.java .. I got this code from a question posted by other user and this is supposed to be the working code but it's not printing anything

Test.java:

package bachelor;
import java.io.BufferedReader; 
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;
import org.w3c.dom.Element;

import bachelor.actions.SampleAction;

import java.io.File;
import java.lang.Character.UnicodeBlock;
import java.math.BigInteger;
import java.util.Hashtable;


public class Tester {


     private static void printLines(String name, InputStream ins) throws Exception {
         String line = null;
         BufferedReader in = new BufferedReader(new InputStreamReader(ins));
         while ((line = in.readLine()) != null) {
             System.out.println(name + " " + line);
         }
       }



    public static void main(String[] args){


        try {
            Process processCompile = Runtime.getRuntime().exec("javac Main.java");
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        Process processRun = null;
        try {
            processRun = Runtime.getRuntime().exec("java Main");
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        try {
            printLines(" stdout:", processRun.getInputStream());
            printLines(" stderr:", processRun.getErrorStream());
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        }}

Main.java

public class Main {

    public static void main (String args[]){
        System.out.println("DONE SUCCESSFULLY");
    }


}

This is the error that appears although I put the 2 classes in the same package

javac Main.java stderr: javac: file not found: Main.java
javac Main.java stderr: Usage: javac <options> <source files>
javac Main.java stderr: use -help for a list of possible options
javac Main.java exitValue() 2
java Main stderr: Exception in thread "main" java.lang.NoClassDefFoundError: Main
java Main stderr: Caused by: java.lang.ClassNotFoundException: Main
java Main stderr:   at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
java Main stderr:   at java.security.AccessController.doPrivileged(Native Method)
java Main stderr:   at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
java Main stderr:   at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
java Main stderr:   at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
java Main stderr:   at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
java Main exitValue() 1