@Transactional 注解配置

Question

嗨，我正在学习 Java 核心研究之后的 Spring 框架。 我正在制作非常简单的 CRUD MVC 应用程序。 有一个问题@Transactional 注释不起作用。 在这件事上更有经验的人可以帮助我吗？ 堆栈：（Java，Spring，Hibernate，Maven）。

Pom.xml

<?xml version="1.0" encoding="UTF-8"?>


<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.adrianzaplata</groupId>
<artifactId>hibernate-tutorial</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>

<name>hibernate-tutorial Maven Webapp</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>

<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <maven.compiler.source>1.8</maven.compiler.source>
  <maven.compiler.target>1.8</maven.compiler.target>
    <failOnMissingWebXml>false</failOnMissingWebXml>
</properties>

<dependencies>
  <dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.11</version>
    <scope>test</scope>
  </dependency>


  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.2.12.RELEASE</version>
  </dependency>


  <dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <version>5.4.27.Final</version>
  </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-orm -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>5.3.3</version>
    </dependency>


    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
  <dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.23</version>

  </dependency>

  <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1.0</version>
    <scope>provided</scope>
  </dependency>

  <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-c3p0 -->
  <dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-c3p0</artifactId>
    <version>5.4.27.Final</version>
  </dependency>

  <!-- https://mvnrepository.com/artifact/jstl/jstl -->
  <dependency>
    <groupId>jstl</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
  </dependency>



</dependencies>

<build>
  <finalName>hibernate-tutorial</finalName>
  <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
    <plugins>
      <plugin>
        <artifactId>maven-clean-plugin</artifactId>
        <version>3.1.0</version>
      </plugin>
      <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
      <plugin>
        <artifactId>maven-resources-plugin</artifactId>
        <version>3.0.2</version>
      </plugin>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.8.0</version>
      </plugin>
      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>
        <version>2.22.1</version>
      </plugin>
      <plugin>
        <artifactId>maven-war-plugin</artifactId>
        <version>3.2.2</version>
      </plugin>
      <plugin>
        <artifactId>maven-install-plugin</artifactId>
        <version>2.5.2</version>
      </plugin>
      <plugin>
        <artifactId>maven-deploy-plugin</artifactId>
        <version>2.8.2</version>
      </plugin>
    </plugins>
  </pluginManagement>
</build>
</project>

我的配置：

package com.adrianzaplata.project.config;


import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.orm.hibernate5.HibernateTransactionManager;
import org.springframework.orm.hibernate5.LocalSessionFactoryBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

import java.beans.PropertyVetoException;
import java.util.Properties;

@Configuration
@EnableWebMvc
@EnableTransactionManagement
@ComponentScan(basePackages = {"com.adrianzaplata.project"})
public class AppConfig {

    @Bean
    public InternalResourceViewResolver viewResolver()
    {
        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
        viewResolver.setPrefix("/WEB-INF/views/");
        viewResolver.setSuffix(".jsp");
        return viewResolver;
    }
    @Bean(destroyMethod = "close")
    public ComboPooledDataSource comboPooledDataSource() throws PropertyVetoException {
        ComboPooledDataSource cpds = new ComboPooledDataSource();
        cpds.setDriverClass("com.mysql.jdbc.Driver");
        cpds.setJdbcUrl("jdbc:mysql://localhost:3306/hibernate?useSSL=false");
        cpds.setUser("adrian");
        cpds.setPassword("chomik12");

        cpds.setMinPoolSize(5);
        cpds.setMaxPoolSize(20);
        cpds.setMaxIdleTime(30000);

        return cpds;
    }
//
    @Bean
    public LocalSessionFactoryBean beanFactory() throws PropertyVetoException {
        LocalSessionFactoryBean factory = new LocalSessionFactoryBean();
        factory.setDataSource(comboPooledDataSource());
        factory.setPackagesToScan("com.adrianzaplata.project.entities");

        Properties hibernateProperties = new Properties();
        hibernateProperties.setProperty("hibernate.dialect","org.hibernate.dialect.MySQLDialect");
        hibernateProperties.setProperty("hibernate.show_sql","true");
        factory.setHibernateProperties(hibernateProperties);

        return factory;

    }


    @Bean
    public PlatformTransactionManager hibernateTransactionManager() throws PropertyVetoException {
        HibernateTransactionManager transactionManager
                = new HibernateTransactionManager();
        transactionManager.setSessionFactory(beanFactory().getObject());
        return transactionManager;
    }






}

我的初始化 class 而不是 web.xml

package com.adrianzaplata.project.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;

@Configuration
public class AppInit extends AbstractAnnotationConfigDispatcherServletInitializer {

    @Override
    protected Class<?>[] getRootConfigClasses() {
        return null;
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        Class[] confClasses = {AppConfig.class};
        return confClasses;
    }

    @Override
    protected String[] getServletMappings() {
        String[] mappings = {"/"};
        return mappings;
    }
}

Controller

package com.adrianzaplata.project.controllers;


import com.adrianzaplata.project.entities.Customer;
import com.adrianzaplata.project.service.CustomerService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;


@Controller
@RequestMapping("/customer")
public class CustomerController {

    @Autowired
    private CustomerService customerService;

    @GetMapping("/all")
    public String listCustomers(Model model)
    {
       List<Customer> theCustomers = customerService.getAllCustomers();
       model.addAttribute("customers",theCustomers);
        return "customer-all";
    }

    @GetMapping("/showAddForm")
    public String addCustomer(@ModelAttribute("CustomerDTO") Customer customerDTO)
    {
        return "add-customer";
    }

    @PostMapping("/process-add-form")
    public void processCustomer(HttpServletRequest request, HttpServletResponse response, @ModelAttribute("CustomerDTO") Customer customerDTO) throws IOException {
        customerService.addCustomer(customerDTO);

        response.sendRedirect(request.getContextPath()+"/customer/all");
    }




}

At the moment I'm able to read customers from database but method addCustomer doesn't work unless managed transcaction manually inside saveCustomer() method. I suspect that reading customers also does not work by @Transactional annotation.

服务

package com.adrianzaplata.project.service;

import com.adrianzaplata.project.dao.CustomerDao;
import com.adrianzaplata.project.entities.Customer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.List;

@Service
public class CustomerServiceImpl implements CustomerService {

    @Autowired
    private CustomerDao customerDao;

    @Override
    @Transactional
    public List<Customer> getAllCustomers()
    {
        return customerDao.getCustomers();
    }

    @Transactional
    @Override
    public void addCustomer(Customer customer) {
        customerDao.addCustomer(customer);
    }
}

道

package com.adrianzaplata.project.dao;

import com.adrianzaplata.project.entities.Customer;

import org.hibernate.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import java.util.List;

@Repository
public class CustomerDaoImpl implements CustomerDao {


    @Autowired
    private SessionFactory sessionFactory;


    @Override
    public List<Customer> getCustomers() {

        Session session = sessionFactory.openSession();
        try {
            SQLQuery query = session.createSQLQuery("SELECT * from customer");
            query.addEntity(Customer.class);
            List<Customer> customers = query.list();
            return customers;

        } finally {
            session.close();
        }
    }

    @Override
    public void addCustomer(Customer customer) {
        Session session = sessionFactory.openSession();
        session.save(customer);
    }

}

Answer 1

我只是想使用@Transactional 来帮助我减少必须用于hibernate 的样板代码，但是当我使用@Transactional 时，我来自dao class 的逻辑不会执行。 （不查询数据库）。