### Question:
LruCache { public synchronized E get( K key ) { if ( key == null ) { throw new IllegalArgumentException(); } return cache.get( key ); } LruCache( String name, int maxSize ); String getName(); int maxSize(); synchronized void put( K key, E element ); synchronized E remove( K key ); synchronized E get( K key ); synchronized void clear(); synchronized int size(); synchronized Set<K> keySet(); synchronized void resize( int newMaxSize ); void elementCleaned( E element );  }### Answer:
@Test void shouldThrowWhenGettingWithANullKey() { assertThrows( IllegalArgumentException.class, () -> new LruCache<>( "TestCache", 70 ).get( null ) ); }