Question

I am having a problem with seeing subclass attributes in an ArrayList.

Here’s some snippets of the main parts of my code that matter here.

private ArrayList<Person> people = new ArrayList<Person>;

abstract class Person {
String fName;
String lName;
}

public class Employee extends Person {
protected int empID;
}

public class Client extends Person {
protected int clientID;
}

When using a for loop to search by clientID, I am getting

Enterprise.java:134: cannot find symbol
symbol : variable clientID
location: class Person

I have tried with and without instanceof Client on the for loop. I have also tried using Client instead of Person in the for loop parameters.

for(Person x : people) {
if(x.clientID == cid) {
    System.out.println(x);
}

Before turning these into subclasses I had them in an ArrayList of their own kind and everything worked flawlessly.

Any help would be greatly appreciated!

Answer 1

You have to either put them in a seperate list or cast them:

for (Person person : people) {
  if (person instanceof Client) {
    Client client = (Client) person;
    if (client.clientID == cid) {
      System.out.println("found!");
    }
  }
}