protected PathMetadata forMapAccess(Expression<K> key) {
        return PathMetadataFactory.forMapAccess(this, key);
    }
{@code MapPath} represents map paths

@author tiwe

@param <K> key type
@param <V> value type
@param <E> result type for {@code get(K)} results
querydsl-core/src/main/java/com/querydsl/core/types/dsl/MapPath.java