CIS 260 TestArrayList.java

Code

/*
    TestArrayList.java
    David Klick
    CIS 260
    2009-03-23

    This program demonstrates a few features of the ArrayList class.
    Note that the datatypes could easily have been reversed within the
    program so that we were looking up Integers based on String values.
*/

import java.util.*;

public class TestArrayList {
    public static void main(String[] args) {
        ArrayList<Integer> alist = new ArrayList<Integer>();

        // you can add and remove items dynamically
        alist.add(17);
        alist.add(26);
        alist.add(-8);
        alist.add(142);
        alist.remove(1);  // removes item at index
        for (int i : alist) System.out.print(i + " ");
        System.out.println();

        // you can clear out an ArrayList
        alist.clear();

        // if you keep track of object references, you can
        //    check for and remove specific objects
        ArrayList<String> slist = new ArrayList<String>();
        slist.add("C");
        slist.add("I");
        slist.add("S");
        slist.add("2");
        slist.add("6");
        slist.add("0");
        System.out.println(slist.contains("2")); // true
        System.out.println(slist.indexOf("2"));  // 3
        slist.remove("2");
        System.out.println(slist.indexOf("2"));  // -1 (not found)
        for (String s : slist) System.out.print(s + " ");
        System.out.println();
    }
}

/*
    Output:

    17 -8 142
    true
    3
    -1
    C I S 6 0
*/