ArrayList in Java Collections Framework


import java.util.ArrayList;

public class TestArrayList {
    public static void main(String [] args) {
    	// create an empty array list:
    	ArrayList<String> strings = new ArrayList<String>();

    	// no elements in the array list
    	System.out.println(strings.size());
    	
    	strings.add("cat");
    	strings.add("dog");
    	strings.add("mouse");
    	
    	// you can print array lists easily
    	System.out.println(strings);
    	
    	int i = 1;
    	String s = strings.get(i);
    	System.out.println("The element at index " + i + " is \"" + s + "\"");
    	
    	// the array list hasn't changed
    	System.out.println(strings);
    	
    	strings.remove(i);
    	System.out.println(strings);
    	
    	s = strings.get(i);
    	System.out.println("The element at index " + i + " is \"" + s + "\"");
    	
    	strings.add("cat");
    	System.out.println(strings);
    	
    	// remove the first occurrence of "cat"
    	strings.remove("cat");
    	System.out.println(strings);
    	
    	strings.set(i, "cow");
    	System.out.println(strings);
    	
    	// you can use a for-each loop on array lists
        for (String str: strings){
           if (str.charAt(0)== 'c') {
    	      System.out.println(str);
           }
    	}
    }
}


CSci 2101 course web site.

The views and opinions expressed in this page are strictly those of the page author. The contents of this page have not been reviewed or approved by the University of Minnesota.