Detailed code explanation of Spring and Hibernate for Java transaction management learning

<property name="hibernate.current_session_context_class">thread</property>

<property name="hibernate.current_session_context_class">jta</property>

<?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:p="http://www.springframework.org/schema/p" 
 xmlns:context="http://www.springframework.org/schema/context" 
 xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc" 
 xmlns:tx="http://www.springframework.org/schema/tx" 
 xmlns:aop="http://www.springframework.org/schema/aop" 
 xsi:schemaLocation=" 
  http://www.springframework.org/schema/util 
  http://www.springframework.org/schema/util/spring-util-3.1.xsd 
  http://www.springframework.org/schema/beans 
  http://www.springframework.org/schema/beans/spring-beans-3.1.xsd 
  http://www.springframework.org/schema/context 
  http://www.springframework.org/schema/context/spring-context-3.1.xsd 
  http://www.springframework.org/schema/mvc 
  http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd 
  http://www.springframework.org/schema/tx 
  http://www.springframework.org/schema/tx/spring-tx-3.0.xsd 
  http://www.springframework.org/schema/aop 
  http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"> 
 
 <context:component-scan base-package="com.oscar999.trans.sprhib" /> 
 <context:property-placeholder location="classpath:/com/oscar999/trans/sprhib/config.properties" /> 
 <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" 
  destroy-method="close"> 
  <!-- Connection Info --> 
  <property name="driverClassName" value="${jdbc.driver}" /> 
  <property name="url" value="${jdbc.url}" /> 
  <property name="username" value="${jdbc.username}" /> 
  <property name="password" value="${jdbc.password}"></property> 
 </bean> 
 
 <bean id="sessionFactory" 
  class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"> 
  <property name="dataSource" ref="dataSource"></property> 
  <property name="hibernateProperties"> 
   <props> 
    <prop key="hibernate.dialect">org.hibernate.dialect.OracleDialect</prop> 
    <prop key="hibernate.hbm2ddl.auto">update</prop> 
    <prop key="hibernate.show_sql">true</prop> 
    <prop key="hibernate.format_sql">true</prop> 
    <prop key="hibernate.jdbc.batch_size">20</prop> 
    <prop key="hibernate.enable_lazy_load_no_trans">true</prop> 
    <prop key="hibernate.current_session_context_class">org.springframework.orm.hibernate4.SpringSessionContext</prop> 
    <prop key="jdbc.use_streams_for_binary">true</prop> 
   </props> 
  </property> 
  <property name="packagesToScan"> 
   <list> 
    <value>com.oscar999.trans.sprhib.model</value> 
   </list> 
  </property> 
 </bean> 
 
 <!-- Transaction --> 
 <bean id="transactionManager" 
  class="org.springframework.orm.hibernate4.HibernateTransactionManager"> 
  <property name="sessionFactory" ref="sessionFactory" /> 
 </bean> 
 <tx:advice id="txAdvice" transaction-manager="transactionManager"> 
  <tx:attributes> 
   <tx:method name="save*" propagation="REQUIRED" /> 
   <tx:method name="*" read-only="true" /> 
  </tx:attributes> 
 </tx:advice> 
 <aop:config proxy-target-class="true"> 
  <aop:pointcut expression="execution(* com.oscar999.trans.sprhib.dao.ProductDAOImpl.*(..))" id="pointcut" /> 
  <aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut" /> 
 </aop:config> 
 
</beans>

jdbc.driver=oracle.jdbc.driver.OracleDriver 
jdbc.url=jdbc:oracle:thin:@12.6.18.43:1521:orcl 
jdbc.username= 
jdbc.password=oracle

/** 
 * @Title: Product.java 
 * @Package com.oscar999.trans.hibernate 
 * @Description: 
 * @author XM 
 * @date Feb 15, 2017 1:44:47 PM 
 * @version V1.0 
 */ 
package com.oscar999.trans.sprhib.model; 
 
import java.io.Serializable; 
 
import javax.persistence.Column; 
import javax.persistence.Entity; 
import javax.persistence.Id; 
import javax.persistence.Table; 
 
/** 
 * @author XM 
 * 
 */ 
@Entity 
@Table(name = "TEST_PRODUCT") 
public class Product implements Serializable { 
 
 public Product() { 
 } 
 
 @Id 
 @Column(name = "ID") 
 private Integer id; 
 
 @Column(name = "NAME") 
 private String name; 
 
 @Column(name = "PRICE") 
 private String price; 
 
 private static final long serialVersionUID = 1L; 
 
 public Integer getId() { 
  return id; 
 } 
 
 public void setId(Integer id) { 
  this.id = id; 
 } 
 
 public String getName() { 
  return name; 
 } 
 
 public void setName(String name) { 
  this.name = name; 
 } 
 
 public String getPrice() { 
  return price; 
 } 
 
 public void setPrice(String price) { 
  this.price = price; 
 } 
 
}

/** 
 * @Title: ProductDAOImpl.java 
 * @Package com.oscar999.trans.sprhib 
 * @Description: 
 * @author XM 
 * @date Feb 15, 2017 4:15:09 PM 
 * @version V1.0 
 */ 
package com.oscar999.trans.sprhib.dao; 
 
import org.hibernate.Session; 
import org.hibernate.SessionFactory; 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.stereotype.Repository; 
 
import com.oscar999.trans.sprhib.model.Product; 
 
/** 
 * @author XM 
 * 
 */ 
@Repository 
public class ProductDAOImpl { 
 
 @Autowired 
 private SessionFactory sessionFactory; 
 
 public Product findProductById(int id) { 
  Session session = sessionFactory.getCurrentSession(); 
  Product product = (Product) session.get(Product.class, id); 
  return product; 
 } 
  
 public Product saveProduct(Product product) { 
  Session session = sessionFactory.getCurrentSession(); 
  session.save(product); 
  return product; 
 } 
}

package com.oscar999.trans.sprhib; 
 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.stereotype.Service; 
 
import com.oscar999.trans.sprhib.dao.ProductDAOImpl; 
import com.oscar999.trans.sprhib.model.Product; 
 
@Service 
public class ProductServiceImpl { 
 
 @Autowired 
 private ProductDAOImpl productdao; 
 
 public void findProduct(int id) { 
  Product product = productdao.findProductById(id); 
  if (product != null) { 
   System.out.println(product.getName()); 
  } 
 } 
 
 public void saveProduct() { 
  Product product = new Product(); 
  product.setId(2); 
  product.setName("product2"); 
  product.setPrice("price2"); 
  productdao.saveProduct(product); 
 
 } 
}

/** 
 * @Title: TestMain.java 
 * @Package com.oscar999.trans.sprhib 
 * @Description: 
 * @author XM 
 * @date Feb 15, 2017 3:54:54 PM 
 * @version V1.0 
 */ 
package com.oscar999.trans.sprhib; 
 
import org.springframework.context.ApplicationContext; 
import org.springframework.context.support.ClassPathXmlApplicationContext; 
 
/** 
 * @author XM 
 * 
 */ 
public class TestMain { 
 
 /** 
  * @param args 
  */ 
 public static void main(String[] args) { 
  // TODO Auto-generated method stub 
  ApplicationContext applicationContext = new ClassPathXmlApplicationContext("com/oscar999/trans/sprhib/applicationContext.xml"); 
  ProductServiceImpl productService = applicationContext.getBean(ProductServiceImpl.class); 
  //productService.findProduct(1); 
  productService.saveProduct(); 
 } 
 
}

@Service


 @Transactional


 public class UserServiceImpl implements UserService {


  @Autowired


  private UserDao userDao;


 
  public User getUserById(int id) {


   return userDao.findUserById(id);


  }


 }

@Service


 @Transactional


 public class UserServiceImpl implements UserService {


  @Autowired


  private UserDao userDao;


 
  @Transactional(propagation = Propagation.NOT_SUPPORTED)


  public User getUserById(int id) {


   return userDao.findUserById(id);


  }