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class SuperClass {  //Main Bank class maintains all data  during program execution
  private double balance=0;
 
  protected boolean withdraw(double amount) {
	 balance -= amount;
	 return true;	 
  }
 
  protected void overdraft() {  //this method was added at a later date
	balance += 300; //add 300 in case there is an overdraft
	System.out.println("The balance is :" + balance);
  }
}

class SubClass extends SuperClass {	//all users hashave to subclass this to proceed
  public boolean withdraw(double amount) {
    // inputValidation();
    // securityManagerCheck();
    // Login by checking credentials using database and then call a method in SuperClass 
    // that updates the balance field to reflect current balance, other details
    return true;
  }			
 
  public void doLogic(SuperClass sc,double amount) {
    sc.withdraw(amount);
  }
}

public class Affect {
  public static void main(String[] args) {
    SuperClass sc = new SubClass();  //override
    SubClass sub = new SubClass();  //need instance of SubClass to call methods

    if(sc.withdraw(200.0)) { //validate and enforce security manager check 
      sc = new SuperClass(); //if allowed perform the withdrawal
      sub.doLogic(sc, 200.0); //pass the instance of SuperClass to use it
    }
    else
      System.out.println("You do not have permission/input validation failed!");	
      sc.overdraft(); //newly added method, has no security manager checks. Beware!
    }
}