Context:
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context" xmlns:task="http://www.springframework.org/schema/task" xmlns:int="http://www.springframework.org/schema/integration" xmlns:int-ip="http://www.springframework.org/schema/integration/ip" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration-2.2.xsd http://www.springframework.org/schema/integration/ip http://www.springframework.org/schema/integration/ip/spring-integration-ip-2.2.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd"> <context:component-scan base-package="Main.*" /> <aop:aspectj-autoproxy /> <task:annotation-driven/> <tx:annotation-driven transaction-manager="transactionManager" /> <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/db_example" /> <property name="username" value="root" /> <property name="password" value="tully" /> </bean> <!-- server beans --> <bean id="byteArrayCrLfSerializer" class="org.springframework.integration.ip.tcp.serializer.ByteArrayCrLfSerializer" /> <int-ip:tcp-connection-factory id="tcpServerFactory" type="server" port="23234" single-use="false" serializer="byteArrayCrLfSerializer" deserializer="byteArrayCrLfSerializer" /> <int:channel id="serverIn" /> <int:channel id="serverOut" /> <int-ip:tcp-inbound-channel-adapter channel="serverIn" connection-factory="tcpServerFactory"/> <int-ip:tcp-outbound-channel-adapter channel="serverOut" connection-factory="tcpServerFactory"/> <int:service-activator ref="senderService" method="send" input-channel="serverIn"/> <!-- Hibernate --> <bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="packagesToScan" value="org.baeldung.spring.persistence.model" /> <property name="annotatedClasses"> <list> <value>Main.database.dataSet.ComplexDataSet</value> <value>Main.database.dataSet.CameraDataSet</value> <value>Main.database.dataSet.CommunityDataSet</value> <value>Main.database.dataSet.JournalDataSet</value> <value>Main.database.dataSet.RegionDataSet</value> <value>Main.database.dataSet.SpotDataSet</value> <value>Main.database.dataSet.TypeDataSet</value> <value>Main.database.dataSet.VersionDataSet</value> <value>Main.database.dataSet.CountThreadDataSet</value> </list> </property> <property name="hibernateProperties"> <props> <prop key="hibernate.hbm2ddl.auto">validate</prop> <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop> <prop key="hibernate.show_sql">false</prop> </props> </property> </bean> <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager"> <property name="sessionFactory" ref="sessionFactory" /> </bean> SpotDataSet
@Entity @Table(name = "spot") public class SpotDataSet implements Serializable { @Id @Column(name = "spot_id") @GeneratedValue private long spot_id; @Column(name = "maps") private String maps; @ManyToOne(cascade=CascadeType.ALL) @JoinColumn(name="region_id") private RegionDataSet region; @OneToMany(fetch = FetchType.LAZY,mappedBy = "spot") private Set<ComplexDataSet> complexDataSets; ...... } Complexdataset
@Entity @Table(name = "complex") public class ComplexDataSet implements Complex,Serializable { @Id @Column(name = "id") @GeneratedValue private long id; @ManyToOne(cascade = {CascadeType.ALL}) @JoinColumn(name="spot_id") private SpotDataSet spot; @Column(name = "priority") private int priority; @Column(name = "type") private int type; @Column(name = "ip") private String ip; @ManyToOne(cascade = {CascadeType.ALL}) @JoinColumn(name = "version_id") private VersionDataSet version; @ManyToOne(cascade = {CascadeType.ALL}) @JoinColumn(name="community_id") private CommunityDataSet community; @OneToMany(fetch = FetchType.LAZY,mappedBy = "complex") private Set<CameraDataSet> cameraDataSets; ..... } DBService
@Transactional public List<SpotDataSet> getAllSpotDataSet(){ Session session = sessionFactory.getCurrentSession(); MySqlDAO dao = new MySqlDAO(session); return dao.getAllSpotDataSet(); } DAO
public List<SpotDataSet> getAllSpotDataSet(){ Criteria criteria=session.createCriteria(SpotDataSet.class); return (List<SpotDataSet>) criteria.list(); } Main
ApplicationContext ctx=new ClassPathXmlApplicationContext("spring-config.xml"); DBService dbService=ctx.getBean(DBService.class); List<SpotDataSet> spotDataSets=dbService.getAllSpotDataSet(); System.out.println(spotDataSets.get(0).getComplexDataSets().size()); Error
Exception in thread "main" org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: Main.database.dataSet.SpotDataSet.complexDataSets, could not initialize proxy - no Session at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:575) at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:214) at org.hibernate.collection.internal.AbstractPersistentCollection.readSize(AbstractPersistentCollection.java:155) at org.hibernate.collection.internal.PersistentSet.size(PersistentSet.java:160) 
