Structuring Data with Java - Java - page 238

jects of the wrong type don't make it into your collections, and avoiding the need to write
casts when retrieving objects.

Table 7-2 shows some of the most important methods of ArrayList . Equally important,
those listed are also methods of the List interface, which we'll discuss shortly. This means
that the same methods can be used with the older Vector class and several other classes.

Table 7-2. List access methods

Method signature Usage

Add the given element at the end add(Object o)

Insert the given element at the specified position add(int i, Object o)

Remove all element references from the Collection

clear( )

True if the List contains the given Object

contains(Object o)

Return the object reference at the specified position

get(int i)

Return the index where the given object is found, or -1

indexOf(Object o)

remove(Object o)remove(int i) Remove an object by reference or by position

Return an array containing the objects in the Collection toArray( )

ArrayListDemo stores data in an ArrayList and retrieves it for processing:

public public class class ArrayListDemo ArrayListDemo {

public public static void main ( String [] argv ) {

ArrayList < Date > al = new

static void

new ArrayList <>();

// Create a source of Objects
StructureDemo source = new

new StructureDemo ( 15 );

// Add lots of elements to the ArrayList...
al . add ( source . getDate ());
al . add ( source . getDate ());
al . add ( source . getDate ());

// Print them out using old-style for loop to index number.