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package org.example;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.stream.Collectors;

public class LoadBalancer {

    Map<String, Instance> instances = new HashMap<>();

    public void addInstance(Instance instance) {
        if (instances.size() > 9) {
            throw new RuntimeException("Max instances");
        }

        instances.put(instance.getAddress(), instance);
    }

    public List<String> gatAllInstances() {
        return instances.values().stream()
            .map(Instance::getAddress)
            .collect(Collectors.toList());
    }

    public Instance getRandomInstance() {
        Random random = new Random();

        final int randomId = random.nextInt(instances.size());

        return instances.get(String.valueOf(randomId));
    }
}