java - 延迟初始化不起作用

Question

我有一个 Web 项目，我正在使用 Spring 来管理我的 EntityManager，但我遇到了LazyInitialization. 我正在使用openEntityManagerInView，但它无法正常工作。

我认为这与我的pom.xml. 请问，谁能告诉我我的项目有什么问题？

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" 
   xmlns="http://java.sun.com/xml/ns/javaee" 
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
   xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
   http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
  <filter>
    <filter-name>
      openEntityManagerInViewFilter
    </filter-name>
    <filter-class>
      org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter
    </filter-class>
  </filter>

  <!-- Include this if you are using Hibernate -->
  <filter-mapping>
    <filter-name>openEntityManagerInViewFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <filter-mapping>  
    <filter-name>PrimeFaces FileUpload Filter</filter-name> 
    <servlet-name>Faces Servlet</servlet-name> 
  </filter-mapping>

  <filter>  
    <filter-name>PrimeFaces FileUpload Filter</filter-name>     
    <filter-class>org.primefaces.webapp.filter.FileUploadFilter</filter-class> 
  </filter> 

  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/applicationContext.xml</param-value>
  </context-param>

  <listener>
    <listener-class>
      org.springframework.web.context.request.RequestContextListener
    </listener-class>
  </listener>
  <listener>
    <listener-class>
      org.springframework.web.context.ContextLoaderListener
    </listener-class>
  </listener>

  <context-param>
    <param-name>javax.faces.PROJECT_STAGE</param-name>
    <param-value>Development</param-value>
  </context-param>

  <servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>/faces/*</url-pattern>
  </servlet-mapping>

  <session-config>
    <session-timeout>30</session-timeout>
  </session-config>

  <welcome-file-list>
    <welcome-file>faces/index.xhtml</welcome-file>
  </welcome-file-list>

  <context-param>
    <param-name>primefaces.THEME</param-name>
    <param-value>bootstrap</param-value>
  </context-param>
</web-app>

pom.xml

    <project xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven- 4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.labcon</groupId>
  <artifactId>projetoCongresso</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>projetoCongresso</name>
  <url>http://maven.apache.org</url>
  <properties>
    <endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <dependencies>
    <dependency>
      <groupId>com.sun.faces</groupId>
      <artifactId>jsf-api</artifactId>
      <version>2.1.6</version>
    </dependency>
    <dependency>
      <groupId>com.sun.faces</groupId>
      <artifactId>jsf-impl</artifactId>
      <version>2.1.10</version>
    </dependency> 
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>
    <dependency>
      <groupId>javax.persistence</groupId>
      <artifactId>persistence-api</artifactId>
      <version>1.0</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>3.2.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-expression</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-beans</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aop</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context-support</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-orm</artifactId>
      <version>3.1.2.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>3.1.2.RELEASE</version> 
    </dependency>
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate</artifactId>
      <version>3.2.6.ga</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-annotations</artifactId>
      <version>3.3.1.GA</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-entitymanager</artifactId>
      <version>3.3.2.GA</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.15</version>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-api</artifactId>
      <version>1.6.1</version>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-simple</artifactId>
      <version>1.6.1</version>
    </dependency>
    <dependency> 
      <groupId>commons-collections</groupId>
      <artifactId>commons-collections</artifactId>
      <version>3.1</version> 
    </dependency> 
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.10</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>ejb3-persistence</artifactId>
      <version>1.0.1.GA</version>
    </dependency>
    <dependency>
      <groupId>javax.sql</groupId>
      <artifactId>jdbc-stdext</artifactId>
      <version>2.0</version>
    </dependency>
    <dependency>
      <groupId>javax.transaction</groupId>
      <artifactId>jta</artifactId>
      <version>1.0.1B</version>
    </dependency>
    <dependency>
      <groupId>org.primefaces</groupId>  
      <artifactId>primefaces</artifactId>
      <version>3.4.1</version>
    </dependency>
    <dependency>
      <groupId>org.primefaces.themes</groupId>
      <artifactId>all-themes</artifactId>
      <version>1.0.9</version>
    </dependency>
    <dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>1.2.3-SNAPSHOT</version>
    </dependency>
    <dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>2.5-SNAPSHOT</version>
    </dependency>
    <dependency>
      <groupId>rome</groupId>
      <artifactId>rome</artifactId>
      <version>1.0</version>
    </dependency>
    <dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi</artifactId>
      <version>3.7</version>
    </dependency>   
    <dependency>
      <groupId>com.lowagie</groupId>
      <artifactId>itext</artifactId>
      <version>2.0.7</version>
    </dependency>
    <dependency>
      <groupId>javax</groupId>
      <artifactId>javaee-api</artifactId>
      <version>6.0</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>javax</groupId>
      <artifactId>javaee-web-api</artifactId>
      <version>6.0</version>
      <type>jar</type>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>2.3.2</version>
        <configuration>
          <source>1.6</source>
          <target>1.6</target>
          <compilerArguments>
            <endorseddirs>${endorsed.dir}</endorseddirs>
          </compilerArguments>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-war-plugin</artifactId>
        <version>2.1.1</version>
        <configuration>
          <failOnMissingWebXml>false</failOnMissingWebXml>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <version>2.1</version>
        <executions>
          <execution>
            <phase>validate</phase>
            <goals>
              <goal>copy</goal>
            </goals>
            <configuration>
              <outputDirectory>${endorsed.dir}</outputDirectory>
              <silent>true</silent>
              <artifactItems>
                <artifactItem>
                  <groupId>javax</groupId>
                  <artifactId>javaee-endorsed-api</artifactId>
                  <version>6.0</version>
                  <type>jar</type>
                </artifactItem>
              </artifactItems>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  <repositories>
    <repository>
      <url>http://download.java.net/maven/2/</url>
      <id>jsf20</id>
      <layout>default</layout>
      <name>Repository for library Library[jsf20]</name>
    </repository>
    <repository>
      <url>http://repo1.maven.org/maven2/</url>
      <id>jstl11</id>
      <layout>default</layout>
      <name>Repository for library Library[jstl11]</name>
    </repository>
    <repository>  
      <id>prime-repo</id>  
      <name>PrimeFaces Maven Repository</name>  
      <url>http://repository.primefaces.org</url>  
      <layout>default</layout>  
    </repository> 
    <repository>
      <releases>
        <enabled>false</enabled>
      </releases>
      <snapshots>
        <enabled>true</enabled>
      </snapshots>
      <id>apache.snapshots</id>
      <name>Apache Snapshot Repository</name>
      <url>https://repository.apache.org/content/repositories/snapshots</url>
    </repository>
  </repositories>
</project>

错误信息：

SEVERE: failed to lazily initialize a collection of role:  com.catalogor3e.entity.Sistema.relacionamentoZonaEtiquetaSistema, no session or session was  closed
org.hibernate.LazyInitializationException: failed to lazily initialize a collection of   role: com.catalogor3e.entity.Sistema.relacionamentoZonaEtiquetaSistema, no session or  session was closed
  Sistema 2
at  org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(Abs tractPersistentCollection.java:358)
at  org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:350)
at  org.hibernate.collection.AbstractPersistentCollection.readSize(AbstractPersistentCollection .java:97)
at org.hibernate.collection.PersistentBag.size(PersistentBag.java:225)
at javax.faces.model.ListDataModel.isRowAvailable(ListDataModel.java:110)
at javax.faces.model.ListDataModel.setRowIndex(ListDataModel.java:185)
at javax.faces.model.ListDataModel.setWrappedData(ListDataModel.java:220)
at javax.faces.model.ListDataModel.<init>(ListDataModel.java:79)
at javax.faces.component.UIData.getDataModel(UIData.java:1804)
at             javax.faces.component.UIData.setRowIndexWithoutRowStatePreserved(UIData.java:484)
at javax.faces.component.UIData.setRowIndex(UIData.java:473)
at   com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:81)
at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:820)
at javax.faces.component.UIData.encodeBegin(UIData.java:1118)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:52)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:43)
at  org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:51)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:59)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:43)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:57)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:43)
at org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:51)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:59)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:43)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:57)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:43)
at org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:51)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1764)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1760)
at javax.faces.render.Renderer.encodeChildren(Renderer.java:168)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1757)
at   com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewConte xtImpl.java:518)
at  com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183)
at javax.faces.component.UIForm.visitTree(UIForm.java:354)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1601)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1601)
at  com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java: 376)
at  com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:297)
at  javax.faces.context.PartialViewContextWrapper.processPartial(PartialViewContextWrapper.java :183)
at javax.faces.component.UIViewRoot.encodeChildren(UIViewRoot.java:981)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1757)
at   com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:409)
at  com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at  org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
at    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)

应用程序上下文.xml

<?xml version="1.0" encoding="windows-1252"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.0.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">

  <!-- Seta anotaçoes para serem  <context:annotation-config />usadas pelo Spring -->
  <context:annotation-config />

  <!-- Define o pacote onde o Spring vai procurar por beans anotados --> 
  <context:component-scan base-package="com.labcon.projetocongresso.dao,  com.labcon.projetocongresso.service" />

  <!-- define que as transaçoes irao ser anotadas -->
  <tx:annotation-driven />

  <bean id="dataSource"  class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
    <property name="url" value="jdbc:mysql://localhost:3306/bancodedados"/>
    <property name="username" value="root"/>
    <property name="password" value="852456"/>
  </bean>

  <bean id="entityManagerFactory"  class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="persistenceUnitName" value="projetoCongressoPU" />
    <property name="dataSource" ref="dataSource" />
    <property name="jpaVendorAdapter">
      <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
        <property name="databasePlatform"  value="org.hibernate.dialect.MySQLDialect" />
        <property name="showSql" value="true" /> 
      </bean>
    </property>
  </bean>

  <!-- Configuracao do gerente de transacoes do Spring -->
  <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory" />
  </bean>
</beans>

DAO 的配置如下：

@Repository("sistemasDAO")
public class SistemasDAO {

  @PersistenceContext
  private EntityManager entityManager;

  public SistemasDAO() {

  }

  public List<Sistema> getTodosOsSistemas() {

    Query query = entityManager.createQuery("select sistemas from Sistema sistemas");
    List<Sistema> sistemas = query.getResultList();

    return sistemas; 
  }

  //methods hidden
}

Answer 1

正如@gerrytan 建议的那样，这很可能是因为您没有在事务中访问集合。在尝试对集合进行任何访问时，数据库会话已经关闭。

您可以尝试将 添加@Transactional到您的SistemasDao类中以通过这种方式启用事务管理。