Method containsKey

lib/java/util/HashMap.java:397–401

Returns whether this map contains the specified key. @param key the key to search for. @return true if this map contains the specified key, false otherwise.

(Object key)

     *         {@code false} otherwise.
     */
    @Override
    public boolean containsKey(Object key) {
        Entry<K, V> m = getEntry(key);
        return m != null;
    }

    /**
     * Returns whether this map contains the specified value.