What are lists?

Lists are data structures, much like arrays. The differences being,

1. Lists must hold objects

Arrays can hold a collection of primitive data types or a collection of objects, while lists can hold a collection of objects, not primitive data types.

2. Lists grow as required

The size of array needs to be specified at the time of creating an array. The size of a list need not be specified. You can add as many items as you want to a list (permitting system memory).

3. Lists have a range of instance methods

With arrays (assuming array name is arr), the only operators you have to work with are arr.length and arr[i]. Anything and everything you need to do must be done using these two operators. Several life-saving methods are applicable on list objects, such as:

• get(int) //similar to arr[i]
• size() //similar to arr.length
• add(Object) //add item at the end of the list
• remove(Object) //parameter represents item to be removed
• remove(int) //parameter represents index
• indexOf(Object) //parameter represents item being searched
• lastIndexOf(Object) //parameter represents item being searched