Detailed explanation of JAVA custom exception usage example

public class Work2 {

 public static void main(String[] args) {
  ExceptionGenerator exceptionGenerator = new ExceptionGenerator();

  // Handle the first custom compile time exception  try {
   ();
  } catch (MyFirstException e) {
   ();
  }

  // Handle the second custom runtime exception  try {
   ();
  } catch (MySecondException e) {
   ();
  }

  // Handle the third custom compile time exception  try {
   ();
  } catch (MyThirdException e) {
   ();
  }
 }

}

class ExceptionGenerator {

 // Throw the first compile-time exception public void genFirstException() throws MyFirstException {
  throw new MyFirstException("The first compile-time exception");
 }

 // Throw the second runtime exception public void genSecondException() {
  throw new MySecondException("Exception of the second runtime type");
 }
 // Throw the second compile time exception public void genThirdException() throws MyThirdException {
  throw new MyThirdException("The third compile-time exception");
 }
}

/*
   The first custom compile time exception
  */
class MyFirstException extends Exception {

 public MyFirstException(String msg) {
  super(msg);
 }
}
/*
   The second custom runtime exception
  */
class MySecondException extends RuntimeException {
 public MySecondException(String msg) {
  super(msg);
 }
}
/*
   The third type of custom compile time exception
  */
class MyThirdException extends Exception {
 public MyThirdException(String msg) {
  super(msg);
 }
}