ArrayLists and Iterators

Read this chapter about lists and the useful methods that are available for adding and inserting elements into a list. 

28. Details


Answer:

indexOf returns 2

Details

ArrayListPhoneThings are getting a little complicated. It would be good to look at some details.

  1. An ArrayList of entries is constructed
  2. Several Entry objects are put into the list.
  3. target Entry object is created.
  4. The indexOf() searches for the target in the list.
    • The equals(Object) method of Entry is used.
    • The picture shows the third comparison (which returns true).
  5. A match is found at cell number 2

The indexOf(Object) method is a member of the ArrayList, but it uses the equals(Object) method of Entry.


Question 27:

Would playing with the program help?