Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
1.3k views
in Technique[技术] by (71.8m points)

java - Do we have a MultiBiMap ?

As we now, there is the concept of BiMap and multiMap but is there a multiBiMap ? so what do I mean by this. In multiMap you have one-to-many relationship between K and V, a single key can be associated to multiple value, hence the name. In bi map you have K,V pair which is bi-directional mean you can get V,K relationship as well. Like having a two regular maps but synchronized. I need a bi directional multi map where you combine these two concepts.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)
import java.util.Set;

import com.google.common.collect.HashMultimap;
import com.google.common.collect.SetMultimap;

public class ManyToMany<K, V> {
    private final SetMultimap<K, V> keysToValues = HashMultimap.create();

    private final SetMultimap<V, K> valuesToKeys = HashMultimap.create();

    public Set<V> getValues(K key) {
        return keysToValues.get(key);
    }

    public Set<K> getKeys(V value) {
        return valuesToKeys.get(value);
    }

    public boolean put(K key, V value) {
        return keysToValues.put(key, value) && valuesToKeys.put(value, key);
    }

    public boolean putAll(K key, Iterable<? extends V> values) {
        boolean changed = false;
        for (V value : values) {
            changed |= put(key, value);
        }
        return changed;
    }
}

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...