Question

In this problem, you will complete several classes involving boxes, locks, keys and secrets. Follow the specifications in the starter files for the classes. You can run the javadoc program to generate the API (see Tutorial 2) for the classes.

A box has a secret inside it (and maybe a key!) and can be locked. In order to open a box, you need the right key to unlock the lock. Secrets.java will be a program that takes an array of boxes and an array of keys and tries to open as many boxes as it can with those keys to find as many secrets as possible and returns the Proofs that if found them. Remember, a box can also contain a key to another box!

You need to complete the following classes: Lock, Box, and Secrets. You must submit these files.

The following classes are provided: Key, Proof and Secret. Do not change these classes. We will delete these files if you submit them and use our own copies.

package comp1406a2;

public class Secrets {
    /** find all secrets that can be found using the input boxes and keys
     *
     * @param boxes is a list (arrau) of boxes
     * @param keys is a list (array) of keys
     * @return a list (array) of proofs for every secret that can be
     *         extracted from the input boxes and keys. Order does not matter.
     */
    public Proof[] findSecrets(Box[] boxes, Key[] keys){
        return null;
    }
}

Answer 1

        public Proof[] findSecrets(Box[] boxes, Key[] keys) {
                
                ArrayList<Proof> proofs = new ArrayList<>();
                
                for(Key k: keys) {
                        for(Box b: boxes) {
                                if(b.getLock().unlock(k)) {
                                        proofs.add(new Proof(b.getSecret(), b, k));
                                }
                        }
                }
                
                Proof result[] = new Proof[proofs.size()];
                proofs.toArray(result);
                return result;
        }