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Answer:

ArrayList<String> names = new ArrayList<String>();

This creates an ArrayList with cells that point to String objects.


ArrayList<E> (Review)

ArrayList after three add operations
import java.util.* ;

public class ArrayListEg
{

  public static void main ( String[] args)
  {
    // Create an ArrayList that holds references to String
    ArrayList<String> names = new ArrayList<String>();

    // Add three String references
    names.add("Amy");
    names.add("Bob");
    names.add("Cindy");
       
    // Access and print out the three String Objects
    System.out.println("element 0: " + names.get(0) );
    System.out.println("element 1: " + names.get(1) );
    System.out.println("element 2: " + names.get(2) );
  }
}


The ArrayList in the above program (from chapter 85) holds references to String objects.

The Java API includes ArrayList<E>, which is a generic class. The E in this expression is a type variable. This specifies the type of object the ArrayList will hold. The value given to the type variable must be a type of object (a class.) For example, these statements construct ArrayLists that hold (references to) different classes of objects:

ArrayList<String> names = new ArrayList<String>();

ArrayList<String> data = new ArrayList<Integer>();

ArrayList<String> sizes = new ArrayList<Double>();

ArrayList<String> accounts = new ArrayList<MyType>();

Each declaration uses the class ArrayList<E> from the java.util package, but tailors it to work with the specified class.


QUESTION 2:

(Trick Question:) Is the following statement likely to work?

ArrayList<int> intList = new ArrayList<int>();
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