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javaarraylist

Remove last element of a list


I've been tasked to do the below in a newbie Java tutorial on ArrayList

// 1) Declare am ArrayList of strings
    // 2) Call the add method and add 10 random strings
    // 3) Iterate through all the elements in the ArrayList
    // 4) Remove the first and last element of the ArrayList
    // 5) Iterate through all the elements in the ArrayList, again.

Below is my code

import java.util.ArrayList;
import java.util.Random;

public class Ex1_BasicArrayList {

    public static void main(String[] args) {
        ArrayList<String> list = new ArrayList<String>();
        for (int i = 0; i <= 10; i++){
            Random rand = new Random();
            String randy = String.valueOf(rand);
            list.add(randy );
        }
        for (int i = 0; i < list.size(); i++){
            System.out.print(list.get(i));
        }   
        list.remove(0);
        list.remove(list.size());

        for (int i = 0; i < list.size(); i++){
            System.out.print(list.get(i));
        }
    }
}

The code runs, but I get the below error message when it runs. Any ideas on what I'm doing wrong?

[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@6bc7c054Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 10, Size: 10
    at java.util.ArrayList.rangeCheck(Unknown Source)
    at java.util.ArrayList.remove(Unknown Source)
    at apollo.exercises.ch08_collections.Ex1_BasicArrayList.main(Ex1_BasicArrayList.java:23)

Solution

  • List indices go from 0 to list.size() - 1. Exceeding the upper bound results in the IndexOutOfBoundsException

    list.remove(list.size() - 1);