How to use MySQL's full text search from JPA

Question

I want to use MySQL's full text search features using JPA, without having to use a native query.

I am using EclipseLink, which has a function to support native SQL commands: FUNC. However, the help examples only show this being use with simple MySQL functions. My best effort attempt to get it to work with MATCH & AGAINST is as follows:

@PersistenceContext(name="test")
EntityManager em;

Query query = em.createQuery("SELECT person FROM People person WHERE FUNC('MATCH', person.name) FUNC('AGAINST', :searchTerm)");
...
query.getResultList();

Which gives the following exception:

Caused by: NoViableAltException(32@[()* loopback of 822:9: (m= MULTIPLY right= arithmeticFactor | d= DIVIDE right= arithmeticFactor )*])
    at org.eclipse.persistence.internal.libraries.antlr.runtime.DFA.noViableAlt(DFA.java:159)
    at org.eclipse.persistence.internal.libraries.antlr.runtime.DFA.predict(DFA.java:116)
    at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.arithmeticTerm(JPQLParser.java:4557)
    ... 120 more

I am open to alternatives other that using the FUNC method.

I am using EJB 3 and EclipseLink 2.3.1.

Answer 1

An improved answer of @Markus Barthlen which works for Hibernate.

Create custom dialect

public class MySQLDialectCustom extends MySQL5Dialect {
  public MySQLDialect() {
    super();
    registerFunction("match", new SQLFunctionTemplate(StandardBasicTypes.DOUBLE,
        "match(?1) against  (?2 in boolean mode)"));
  }
}

and register it by setting hibernate.dialect property.

Use it

in JPQL:

Query query = entityManager
    .createQuery("select an from Animal an " +
             "where an.type = :animalTypeNo " +
             "and match(an.name, :animalName) > 0", Animal.class)
    .setParameter("animalType", "Mammal")
    .setParameter("animalName", "Tiger");
List<Animal> result = query.getResultList();
return result;

or with Criteria API:

CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<Animal> criteriaQuery = criteriaBuilder.createQuery(Animal.class);
Root<Animal> root = criteriaQuery.from(Animal.class);

List<Predicate> predicates = new ArrayList<>();

Expression<Double> match = criteriaBuilder.function("match", Double.class, root.get("name"),
criteriaBuilder.parameter(String.class, "animalName"));

predicates.add(criteriaBuilder.equal(root.get("animalType"), "Mammal"));
predicates.add(criteriaBuilder.greaterThan(match, 0.));

criteriaQuery.where(predicates.toArray(new Predicate[]{}));

TypedQuery<Animal> query = entityManager.createQuery(criteriaQuery);
List<Animal> result = query.setParameter("animalName", "Tiger").getResultList();

return result;

Some more details in this blog post: http://pavelmakhov.com/2016/09/jpa-custom-function