I am trying to implement Optimistic locking in-order to avoid lost update situation. In my application when two user fetch same record and the first user updates it with some changes. This change is not visible to the second user who view the same record and he makes some changes by himself and updates it. Due to which the first persons change is lost. In-order to prevent this I have written the following but still the issue persist. I am new to this concept, not able to identify the issue.
I have tried to achieve this by reading doc 11.3.4. Customizing automatic versioning section.
The configuration file
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 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/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"> <tx:annotation-driven transaction-manager="txManager"/> <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"/> </bean> <bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate"> <property name="sessionFactory" ref="sessionFactory"/> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"> <property name="dataSource" ref="dataSource"/> <property name="annotatedClasses"> <list> <value>server.bo.Dept</value> <value>server.bo.Emp</value> </list> </property> <property name="hibernateProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.SQLServer2008Dialect</prop> <prop key="hibernate.show_sql">false</prop> </props> </property> </bean> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="net.sourceforge.jtds.jdbc.Driver"/> <property name="url" value="${db.url}"/> <property name="username" value="${db.username}"/> <property name="password" value="${db.password}"/> </bean> <bean id="deptDAO" class="server.dao.DeptDAOImpl"> <property name="hibernateTemplate" ref="hibernateTemplate"/> </bean> </beans>
Entity Class
@Entity @Table(name = "Dept") @org.hibernate.annotations.Entity(dynamicUpdate = true,optimisticLock = OptimisticLockType.ALL) public class Dept{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "ID") Long id; @OneToMany(cascade = CascadeType.REMOVE, fetch = FetchType.EAGER, mappedBy = "deptId") @Fetch(FetchMode.SELECT) @OrderBy(value = "id DESC") List<Emp> Emplist; public Dept() {} // Getters and setters }
DAO Impl
public class DeptDAOImpl extends HibernateDaoSupport implements DeptDAO { @Transactional(readOnly = true, propagation = Propagation.REQUIRED, isolation = Isolation.REPEATABLE_READ) public Dept getDeptById(Long id) { Object param[] = new Object[]{id}; String query = "select d from Dept d where d.id=? and d.deleted='0'"; List<Dept> deptDetailsList = getHibernateTemplate().find(query,param); Dept deptDetails = null; if(deptDetailsList !=null && deptDetailsList .size()>0) deptDetails = (Dept)deptDetailsList.get(0); return deptDetails ; } @Transactional(readOnly = false, propagation = Propagation.REQUIRED, isolation = Isolation.REPEATABLE_READ) public long updateDept(Dept dept) { if (dept.getId() == null) { getSession().save(dept); } else { getSession().update(dept); } if (dept.getEmplist() != null) { final int size = dept.getEmplist().size(); for (int i = size - 1; i >= 0; i--) { Emp emp = dept.getEmplist().get(i); if (emp.getDeptId() == null) { emp.setDeptId(dept.getId()); } if (RecordStatus.NEW.equals(emp.getRecordStatus())) { getSession().save(emp); } else if (RecordStatus.DELETED.equals(emp.getRecordStatus())) { getSession().delete(emp); } else if (RecordStatus.MODIFIED.equals(emp.getRecordStatus())) { getSession().update(emp); } } } return dept.getId(); } }
Thanks in advance