CustomNPC-Plus/src/main/java/nikedemos/markovnames/HashMap2D.java

package nikedemos.markovnames;

import java.util.HashMap;
import java.util.Map;

public class HashMap2D<T1, T2, T3> {

    public final Map<T1, Map<T2, T3>> mMap;

/*
 https://stackoverflow.com/a/10299689/9355344
 */

    public HashMap2D() {
        mMap = new HashMap<T1, Map<T2, T3>>();
    }

    /**
     * Associates the specified value with the specified keys in this map (optional operation). If the map previously
     * contained a mapping for the key, the old value is replaced by the specified value.
     *
     * @param key1  the first key
     * @param key2  the second key
     * @param value the value to be set
     * @return the value previously associated with (key1,key2), or <code>null</code> if none
     * @see Map#put(Object, Object)
     */
    public T3 put(T1 key1, T2 key2, T3 value) {
        Map<T2, T3> map;
        if (mMap.containsKey(key1)) {
            map = mMap.get(key1);
        } else {
            map = new HashMap<T2, T3>();
            mMap.put(key1, map);
        }

        return map.put(key2, value);
    }

    /**
     * Returns the value to which the specified key is mapped, or <code>null</code> if this map contains no mapping for
     * the key.
     *
     * @param key1 the first key whose associated value is to be returned
     * @param key2 the second key whose associated value is to be returned
     * @return the value to which the specified key is mapped, or <code>null</code> if this map contains no mapping for
     * the key
     * @see Map#get(Object)
     */
    public T3 get(T1 key1, T2 key2) {
        if (mMap.containsKey(key1)) {
            return mMap.get(key1).get(key2);
        } else {
            return null;
        }
    }

    /**
     * Returns <code>true</code> if this map contains a mapping for the specified key
     *
     * @param key1 the first key whose presence in this map is to be tested
     * @param key2 the second key whose presence in this map is to be tested
     * @return Returns true if this map contains a mapping for the specified key
     * @see Map#containsKey(Object)
     */
    public boolean containsKeys(T1 key1, T2 key2) {
        return mMap.containsKey(key1) && mMap.get(key1).containsKey(key2);
    }

    public void clear() {
        mMap.clear();
    }

}