FooService.java

package com.jamesward;


import java.util.List;

import org.springframework.flex.remoting.RemotingDestination;
import org.springframework.stereotype.Repository;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Root;

@Repository
@Service
@RemotingDestination
public class FooService
{

  @PersistenceContext
  private EntityManager entityManager;

  //in EE 6
  @Inject Validator validator; //@Resource works too

  @Transactional
  public Foo getFooById(String id)
  {
    return entityManager.find(Foo.class, id);
  }

  @Transactional
  public List<Foo> getAll()
  {
    CriteriaQuery<Foo> criteriaQuery = entityManager.getCriteriaBuilder().createQuery(Foo.class);
    Root<Foo> rootFoo= criteriaQuery.from(Foo.class);
    criteriaQuery.select(rootFoo);
    return entityManager.createQuery(criteriaQuery).getResultList();
  }

  @Transactional
  public Foo create(Foo foo)
  {
    validate(foo);
    entityManager.persist(foo);
    //entityManager.flush();
    return foo;
  }

  private void validate(Foo foo)
  {
    Set<Constraintviolation<?>> errors = validator.validate(foo);
    if (errors.size() > 0) {
        //raise some exception like constraintViolationException
    }
  }

  @Transactional
  public Foo update(Foo foo)
  {
    validate(foo);
    entityManager.merge(foo);
    //entityManager.flush();
    return foo;
  }
  
}