Question

    import java.util.*;

    class AddressBook {
    private static final int DEFAULT_SIZE = 25;
    private Person[] entry;   //getting error - cannot be resolved to a type

    public AddressBook() {
    this( DEFAULT_SIZE);
    }

    public AddressBook(int size) {
    if (size <= 0) {
    throw new IllegalArgumentException("Size must be positive");
     }

     entry = new Person[size];  // cannot be resolved to a type

     System.out.println("array of " + size + " is created");
    }
 }


      import java.util.Scanner;

     class TestAddressBook {
     public static void main(String args[]) {
     AddressBook myBook;
     String inputStr;
     int size;

    Scanner scanner = new Scanner(System.in);

     while(true) {
     System.out.print("array size: " );
     inputStr = scanner.next();

     if (inputStr.equalsIgnoreCase("stop")) {
     break;
      }
     size = Integer.parseInt(inputStr);

     try {
     myBook = new AddressBook(size);

     }
     catch (IllegalArgumentException e) {


      }
      System.out.println("Exception thrown: size = " + size);
     }
     }

     }

I can’t figure out what type I am supposed to use with the array to get everything to work properly.
private Person[] entry; //getting error – cannot be resolved to a type
….
entry = new Person[size]; // cannot be resolved to a type

Answer 1

Where is Person defined? at the very least, adding the following:

class Person {}

will allow it to compile. Otherwise, it doesn’t know what you mean when you create Person arrays.