Java How to search if user input is equal to something in my array

Question

Hello my goal is to get the user to input some customerID value and some videoID how would I check to make sure the user inputs a correct customerID and videoID in my array I have made for these fields and tell the user they have inputted the wrong ID. This is what i have so far for my code

    public static void HireVideo(){

        System.out.println("Enter Customer ID");
        String customerID = sc.next();
        System.out.println("Enter Video ID");
        String videoID = sc.next();

        HireList.add(new Hire(customerID, videoID));
    }

see http://stackoverflow.com/questions/1128723/in-java-how-can-i-test-if-an-array-contains-a-certain-value — naresh, Apr 03 '14 at 06:15
could u show me how i would u ArrayList.contains in this context? — user3479903, Apr 03 '14 at 06:24

score 1 · Answer 1 · answered Sep 01 '14 at 14:51

in an effort to be as close to your code as possible (i.e. what I assume is a static list wrapper class).

public class HireList {
    private static List<Hire> hires = new ArrayList<Hire>();

    public static void add(Hire hire) {
        hires.add(hire);
    }

    public static boolean contains(Hire other) {
        return hires.contains(other);
    }
}

the magic however happens in the Hire class:

public class Hire {
    private String customerId;
    private String videoId;

    public Hire(String customerId, String videoId) {
        this.customerId = customerId;
        this.videoId    = videoId;
    }

    @Override
    public int hashCode() {
        int hash = 3;
        hash = 67 * hash + Objects.hashCode(this.customerId);
        hash = 67 * hash + Objects.hashCode(this.videoId);
        return hash;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (this.getClass() != obj.getClass()) {
            return false;
        }
        final Hire other = (Hire) obj;
        if (!this.customerId.equals(other.customerId)) {
            return false;
        }
        if (!this.videoId.equals(other.videoId)) {
            return false;
        }
        return true;
    }
}

List<T>.contains(T other) uses the equals method of T, therefore overriding it will allow us to control the behavior of contains.

test:

public static void main(String[] args) {
    HireList.add(new Hire("1", "1"));
    HireList.add(new Hire("2", "2"));

    System.out.println(HireList.contains(new Hire("2", "2"))); //output: true
}

if contains is all you are concerned with though I would suggest using a HashSet as opposed to a ArrayList.

Java How to search if user input is equal to something in my array

1 Answers1