Why is my code not validating last two requirements?

Question about the task

Caching

Java Collections, Level 4, Lesson 8

Under discussion

I can get exactly the same result as the expected output. Thanks.

The Cache class is a generic class for caching objects.
It works with generic classes that have:
a) a public constructor with one K type parameter;
b) a K getKey() method with any access modifier.

Task:
1. Choose the correct type for the cache field. The Map<K, V> cache field must store keys for which there are active references.
Keys with no active references must be automatically removed from the cache along with their values.
2. Implement the getByKey method:
2.1. Return an object from the cache that matches key.
2.2. If an object doesn't exist in the cache, then use reflection to add a new instance to the cache. See item a).
3. Implement the put method:
3.1. Using reflection, get a reference to the method described in item b).
3.2. Use reflection to allow access to it.
3.3. Using reflection, call the getKey method on obj to get key.
3.4. Add the <key, obj> pair to the cache.
3.5. Return true if the method finishes correctly, otherwise return false. Ignore exceptions.

Requirements:

The cache field must be initialized with a WeakHashMap object.
The getByKey method must return an object from the cache.
The getByKey method must add an object to the cache if it is not already there.
The put method must retrieve the key from the passed object and add a <key, obj> pair to the cache.
The put method must return true if it finishes correctly. Otherwise, it must return false.

package com.codegym.task.task34.task3408; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.Map; import java.util.WeakHashMap; public class Cache<K, V> { private Map<K, V> cache = new WeakHashMap<>(); // TODO: Add your code here public V getByKey(K key, Class<V> clazz) throws Exception { // TODO: Add your code here V value = cache.get(key); if (value == null) { Constructor ctor = clazz.getDeclaredConstructor(key.getClass()); value = (V) ctor.newInstance(key); cache.put(key, value); } return value; } public boolean put(V obj) { // TODO: Add your code here try { Method method = obj.getClass().getMethod("getKey", null); method.setAccessible(true); K key = (K) method.invoke(obj, null); cache.put(key, obj); return true; } catch (NoSuchMethodException e) { return false; } catch (IllegalAccessException e) { return false; } catch (InvocationTargetException e) { return false; } } public int size() { return cache.size(); } }

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