値アクセス用に複数のキーを含むマップを作成するにはどうすればよいですか?

<code class="java">import java.util.HashMap;
import java.util.Map;

class MyMap<K1, K2, V> {
    private Map<K1, V> map1;
    private Map<K2, V> map2;

    public MyMap() {
        map1 = new HashMap<>();
        map2 = new HashMap<>();
    }

    public V getByKey1(K1 key) {
        return map1.get(key);
    }

    public V getByKey2(K2 key) {
        return map2.get(key);
    }

    public boolean containsKey1(K1 key) {
        return map1.containsKey(key);
    }

    public boolean containsKey2(K2 key) {
        return map2.containsKey(key);
    }

    public void put(K1 key1, K2 key2, V value) {
        map1.put(key1, value);
        map2.put(key2, value);
    }
}</code>