Question

我有一个包含一组String的字段来保存和编辑selectManyCheckbox的值。我使用注释@ElementCollection，如中所述 http://docs.oracle.com/javaee/6/tutorial/doc/bnbqa.html 我可以在第一时间保存，但第二次保存时出现以下异常：

引起：javax.servlet.ServletException：懒得初始化失败一个集合，没有会话或会话被关闭 javax.faces.webapp.FacesServlet.service（FacesServlet.java:606） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:329） [jbossweb-7.0.10.Final.jar：] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:248） [jbossweb-7.0.10.Final.jar：] at org.primefaces.webapp.filter.FileUploadFilter.doFilter（FileUploadFilter.java:79） [primefaces-3.3.jar：] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:280） [jbossweb-7.0.10.Final.jar：] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:248） [jbossweb-7.0.10.Final.jar：] at org.jboss.weld.servlet.ConversationPropagationFilter.doFilter（ConversationPropagationFilter.java:62） [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:280） [jbossweb-7.0.10.Final.jar：] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:248） [jbossweb-7.0.10.Final.jar：] at org.jboss.solder.servlet.exception.CatchExceptionFilter.doFilter（CatchExceptionFilter.java:65） [solder-impl-3.1.0.Final.jar:3.1.0.Final] ... 29更多引起： org.hibernate.LazyInitializationException：懒得初始化一个集合，没有会话或会话被关闭 org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException（AbstractPersistentCollection.java:393） [hibernate-core-4.0.1.Final.jar：4.0.1.Final] at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected（AbstractPersistentCollection.java:385） [hibernate-core-4.0.1.Final.jar：4.0.1.Final] at org.hibernate.collection.internal.AbstractPersistentCollection.initialize（AbstractPersistentCollection.java:378） [hibernate-core-4.0.1.Final.jar：4.0.1.Final] at org.hibernate.collection.internal.PersistentSet.add（PersistentSet.java:206） [hibernate-core-4.0.1.Final.jar：4.0.1.Final] at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValuesForModel（MenuRenderer.java:382） [jsf-impl-2.1.5-jbossorg-1.jar：2.1.5-SNAPSHOT] at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValue（MenuRenderer.java:129） [jsf-impl-2.1.5-jbossorg-1.jar：2.1.5-SNAPSHOT] at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue（MenuRenderer.java:315） [jsf-impl-2.1.5-jbossorg-1.jar：2.1.5-SNAPSHOT] at javax.faces.component.UIInput.getConvertedValue（UIInput.java:1030） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at javax.faces.component.UIInput.validate（UIInput.java:960） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at javax.faces.component.UIInput.executeValidate（UIInput.java:1233） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at javax.faces.component.UIInput.processValidators（UIInput.java:698） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at javax.faces.component.UIForm.processValidators（UIForm.java:253） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at javax.faces.component.UIComponentBase.processValidators（UIComponentBase.java:1214） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at javax.faces.component.UIViewRoot.processValidators（UIViewRoot.java:1172） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] at com.sun.faces.lifecycle.ProcessValidationsPhase.execute（ProcessValidationsPhase.java:76） [jsf-impl-2.1.5-jbossorg-1.jar：2.1.5-SNAPSHOT] at com.sun.faces.lifecycle.Phase.doPhase（Phase.java:101） [jsf-impl-2.1.5-jbossorg-1.jar：2.1.5-SNAPSHOT] at com.sun.faces.lifecycle.LifecycleImpl.execute（LifecycleImpl.java:118） [jsf-impl-2.1.5-jbossorg-1.jar：2.1.5-SNAPSHOT] at org.apache.myfaces.extensions.cdi.jsf2.impl.listener.phase.CodiLifecycleWrapper.execute（CodiLifecycleWrapper.java:95） [myfaces-extcdi-jsf20-module-impl-1.0.5.jar：1.0.5] at javax.faces.webapp.FacesServlet.service（FacesServlet.java:593） [jboss-jsf-api_2.1_spec-2.0.0.Final.jar：2.0.0.Final] ... 38更多

我使用JBOSS 7.1.0-Final，Hibernate 4.0.1.Final和JSF 2.0

以下是我的代码：

Test.java

@Entity
@Table(name = "TEST")
@NamedQueries({
    @NamedQuery(name = Test.FIND_BY_ID, query = "select test from Test test where test.id = :id")
})
public class Test implements Serializable {

    private static final long serialVersionUID = -7294677843656741933L;

    public static final String FIND_BY_ID = "test.by.id";

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @ElementCollection(fetch=FetchType.EAGER)
    private Set<String> textes;


    public Test() {
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public Set<String> getTextes() {
        return textes;
    }

    public void setTextes(Set<String> textes) {
        this.textes = textes;
    }
}

test.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:c="http://java.sun.com/jsp/jstl/core">

<body>
    <h:form id="form">
        <h:selectManyCheckbox value="#{formBean.test.textes}">
            <f:selectItem itemLabel="Option 1" itemValue="Option 1" />  
            <f:selectItem itemLabel="Option 2" itemValue="Option 2" />  
            <f:selectItem itemLabel="Option 3" itemValue="Option 3" />  
        </h:selectManyCheckbox>

        <h:commandButton value="Save" action="#{formBean.saveTest}" />
    </h:form>
</body>
</html>

以下是相关来源：

FormBean.java

@Named
@SessionScoped
public class FormBean implements Serializable {

    private static final long serialVersionUID = 6484233109393875203L;

    @EJB
    private ServiceBean serviceBean;

    private Test test;

    public String saveTest() {
        serviceBean.save(test);
        return "test";
    }

    public String createTest() {
        test = new Test();
        return "test";
    }

    public Test getTest() {
        return test;
    }

    public void setTest(Test test) {
        this.test = test;
    }

}

ServiceBean.java

@Stateless
@LocalBean
public class ServiceBean {

    @PersistenceContext
    private EntityManager entityManager;

    public boolean save(Test test) {
        Test dbTest = findTestById(test.getId());
        if (dbTest == null) {
            entityManager.persist(test);
        }
        else {
            entityManager.merge(test);
        }

        return true;
    }

    public Test findTestById(Long id) {
        if (id == null)
            return null;

        TypedQuery<Test> query = entityManager.createNamedQuery(Test.FIND_BY_ID, Test.class);
        query.setParameter("id", id);
        List<Test> results = query.getResultList();

        if (results.isEmpty())
            return null;

        return results.get(0);
    }
}

test_index.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:c="http://java.sun.com/jsp/jstl/core">

<body>
    <h:form>
        <h:commandLink value="Test" action="#{formBean.createTest()}" />
    </h:form>
</body>
</html>

感谢您的帮助阮

Answer 1

我找到了这个问题的解决方案，该解决方案已经公布于： @ElementCollection

以下是我的解决方案：

<强> Test.java

@Entity
@Table(name = "TEST")
@NamedQueries({
    @NamedQuery(name = Test.FIND_BY_ID, query = "select test from Test test where test.id = :id")
})
public class Test implements Serializable {

    private static final long serialVersionUID = -7294677843656741933L;

    public static final String FIND_BY_ID = "test.by.id";

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @ElementCollection
    private Set<String> textes;

    public Test() {
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public Set<String> getTextes() {
        return textes;
    }

    public void setTextes(Set<String> textes) {
        this.textes = textes;
    }
}

<强> test.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:c="http://java.sun.com/jsp/jstl/core">

<body>
    <h:form id="form">
        <h:selectManyCheckbox value="#{formBean.selectedTextes}">
            <f:selectItem itemLabel="Option 1" itemValue="Option 1" />  
            <f:selectItem itemLabel="Option 2" itemValue="Option 2" />  
            <f:selectItem itemLabel="Option 3" itemValue="Option 3" />  
        </h:selectManyCheckbox>

        <h:commandButton value="Save" action="#{formBean.saveTest}" />
    </h:form>
</body>
</html>

<强> FormBean.java

@Named
@SessionScoped
public class FormBean implements Serializable {

    private static final long serialVersionUID = 6484233109393875203L;

    @EJB
    private ServiceBean serviceBean;

    private Test test;

    private Set<String> selectedTextes;

    public String saveTest() {
        serviceBean.save(test, selectedTextes);
        return "test";
    }

    public String createTest() {
        test = new Test();
        return "test";
    }

    // getters and setters
}

<强> ServiceBean.java

@Stateless
@LocalBean
public class ServiceBean {

    @PersistenceContext
    private EntityManager entityManager;

    public boolean save(Test test, Set<String> selectedTextes) {
        Test dbTest = findTestById(test.getId());
        if (dbTest == null) {
            if (selectedTextes != null) {
                test.setTextes(selectedTextes);
            }
            entityManager.persist(test);
        }
        else {
            if (selectedTextes != null) {
                dbTest.setTextes(selectedTextes);
            }
            entityManager.merge(dbTest);
        }

        return true;
    }

    public Test findTestById(Long id) {
        if (id == null)
            return null;

        TypedQuery<Test> query = entityManager.createNamedQuery(Test.FIND_BY_ID, Test.class);
        query.setParameter("id", id);
        List<Test> results = query.getResultList();

        if (results.isEmpty())
            return null;

        return results.get(0);
    }
}

<强> test_index.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:c="http://java.sun.com/jsp/jstl/core">

<body>
    <h:form>
        <h:commandLink value="Test" action="#{formBean.createTest()}" />
    </h:form>
</body>
</html>

阮

Answer 2

从问题到答案的差异：

***************
*** 14,18 ****
        private Long id;

!       @ElementCollection(fetch=FetchType.EAGER)
        private Set<String> textes;

--- 14,18 ----
        private Long id;

!       @ElementCollection
        private Set<String> textes;

***************
*** 47,51 ****
      <body>
        <h:form id="form">
!           <h:selectManyCheckbox value="#{formBean.test.textes}">
                <f:selectItem itemLabel="Option 1" itemValue="Option 1" />
                  <f:selectItem itemLabel="Option 2" itemValue="Option 2" />
--- 47,51 ----
      <body>
        <h:form id="form">
!           <h:selectManyCheckbox value="#{formBean.selectedTextes}">
                <f:selectItem itemLabel="Option 1" itemValue="Option 1" />
                  <f:selectItem itemLabel="Option 2" itemValue="Option 2" />
***************
*** 70,75 ****
        private Test test;

        public String saveTest() {
!           serviceBean.save(test);
            return "test";
        }
--- 70,77 ----
        private Test test;

+       private Set<String> selectedTextes;
+ 
        public String saveTest() {
!           serviceBean.save(test, selectedTextes);
            return "test";
        }
***************
*** 97,107 ****
        private EntityManager entityManager;

!       public boolean save(Test test) {
            Test dbTest = findTestById(test.getId());
            if (dbTest == null) {
                entityManager.persist(test);
            }
            else {
!               entityManager.merge(test);
            }

--- 99,115 ----
        private EntityManager entityManager;

!       public boolean save(Test test, Set<String> selectedTextes) {
            Test dbTest = findTestById(test.getId());
            if (dbTest == null) {
+               if (selectedTextes != null) {
+                   test.setTextes(selectedTextes);
+               }
                entityManager.persist(test);
            }
            else {
!               if (selectedTextes != null) {
!                   dbTest.setTextes(selectedTextes);
!               }
!               entityManager.merge(dbTest);
            }

ElementCollection：懒得初始化集合，没有会话或

2 个答案: