Query By Proxy (QBP)
A java criteria api where path expressions are constructed by invoking methods on a proxy for an entity-class (supports both JPA and Hibernate).
State: Beta
General Advantages:
- Strongly typed
- Covers the entire JPA 1.0 specification
Advantages over JPA 2.0 criteria api:
- No code generation required
- Terse syntax
- Does not require vendor implementation (can be used very soon anywhere jpa is implemented)
- Technique is not jpa specific (can be used to create a comparator)
Usage:
ProxyQuery<Customer> query = queryFactory.createQuery(Customer.class);
Customer customer = query.getRootProxy();
query.andWhere(customer.getFirstName()).equalTo("John");
List<Customer> results = query.find();
--produces the following hql/jpql:
SELECT a FROM Customer a WHERE a.firstName = 'John'