Class TypeRegistry

output/java8/1.4.12/TypeRegistry.java:45–200

@author Sam Harwell

public class TypeRegistry<V> implements Map<Class<?>, V> {
    private final Map<Class<?>, V> backingStore = new HashMap<Class<?>, V>();
    private final Map<Class<?>, Class<?>> cache = new HashMap<Class<?>, Class<?>>();
    public int size() {
        return backingStore.size();
    }

    public boolean isEmpty() {
        return backingStore.isEmpty();
    }

    public boolean containsKey(Object key) {
        if ( cache.containsKey(key) ) {
            return true;
        }
        if ( !(key instanceof Class) ) {
            return false;
        }
        return get(key)!=null;
    }

    @SuppressWarnings("unchecked")
    public boolean containsValue(Object value) {
        return values().contains(value);
    }

    /**
     * {@inheritDoc}
     *
     * @throws AmbiguousMatchException if the registry contains more than value
     * mapped to a maximally-specific type from which {@code key} is derived.
     */

    public V get(Object key) {
        V value = backingStore.get(key);
        if ( value!=null ) {
            return value;
        }
        Class<?> redirect = cache.get(key);
        if ( redirect!=null ) {
            if ( redirect==Void.TYPE ) {
                return null;
            }
            else {
                return backingStore.get(redirect);
            }
        }
        if ( !(key instanceof Class) ) {
            return null;
        }
        Class<?> keyClass = (Class<?>)key;
        List<Class<?>> candidates = new ArrayList<Class<?>>();
        for (Class<?> clazz : backingStore.keySet()) {
            if ( clazz.isAssignableFrom(keyClass) ) {
                candidates.add(clazz);
            }
        }
        if ( candidates.isEmpty() ) {