Method put

lib/java/util/AbstractMap.java:279–281

Maps the specified key to the specified value. @param key the key. @param value the value. @return the value of any previous mapping with the specified key or null if there was no mapping. @throws UnsupportedOperationException if adding to this m

(K key, V value)

     *                support {@code null} keys or values.
     */
    public V put(K key, V value) {
        throw new UnsupportedOperationException();
    }

    /**
     * Copies every mapping in the specified map to this map.