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1   /*
2    * JBoss, Home of Professional Open Source
3    * Copyright 2014, Red Hat, Inc. and/or its affiliates, and individual
4    * contributors by the @authors tag. See the copyright.txt in the
5    * distribution for a full listing of individual contributors.
6    *
7    * Licensed under the Apache License, Version 2.0 (the "License");
8    * you may not use this file except in compliance with the License.
9    * You may obtain a copy of the License at
10   * http://www.apache.org/licenses/LICENSE-2.0
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.jboss.as.quickstarts.kitchensinkjsp.data;
18  
19  import org.jboss.as.quickstarts.kitchensinkjsp.model.Member;
20  import java.util.List;
21  import javax.annotation.PostConstruct;
22  import javax.enterprise.context.RequestScoped;
23  import javax.enterprise.event.Observes;
24  import javax.enterprise.event.Reception;
25  
26  import javax.enterprise.inject.Produces;
27  import javax.inject.Inject;
28  import javax.inject.Named;
29  import javax.persistence.EntityManager;
30  import javax.persistence.criteria.CriteriaBuilder;
31  import javax.persistence.criteria.CriteriaQuery;
32  import javax.persistence.criteria.Root;
33  
34  @RequestScoped
35  public class MemberListProducer {
36      @Inject
37      private EntityManager em;
38  
39      private List<Member> members;
40  
41      // @Named provides access the return value via the EL variable name "members" in the UI (e.g.,
42      // Facelets or JSP view)
43      @Produces
44      @Named
45      public List<Member> getMembers() {
46          return members;
47      }
48  
49      public void onMemberListChanged(@Observes(notifyObserver = Reception.IF_EXISTS) final Member member) {
50          retrieveAllMembersOrderedByName();
51      }
52  
53      @PostConstruct
54      public void retrieveAllMembersOrderedByName() {
55          CriteriaBuilder cb = em.getCriteriaBuilder();
56          CriteriaQuery<Member> criteria = cb.createQuery(Member.class);
57          Root<Member> member = criteria.from(Member.class);
58          // Swap criteria statements if you would like to try out type-safe criteria queries, a new
59          // feature in JPA 2.0
60          // criteria.select(member).orderBy(cb.asc(member.get(Member_.name)));
61          criteria.select(member).orderBy(cb.asc(member.get("name")));
62          members = em.createQuery(criteria).getResultList();
63      }
64  }