SpringBoot 整合 JDBCTemplate

﹏ヽ暗。殇╰゛Y 2023-07-03 02:53 2阅读 0赞

# 前文： #

[SpringBoot 的概述][SpringBoot]

[SpringBoot 项目搭建][SpringBoot 1]

[SpringBoot的核心注解][SpringBoot 2]

### 文章目录 ###

*  前文：
 *  什么是 JDBCTemplate ？
 *  导入相关的依赖
 *  创建数据库
 *  数据库配置
 *  创建实体类
 *  创建数据库访问层
 *  创建业务层
 *  控制器编写
 *  测试

# 什么是 JDBCTemplate ？ #

JDBCTemplate 是 Spring 提供的一套 JDBC 模板框架，利用 AOP 技术来解决直接使用 JDBC 时的大量重复代码的问题。JDBC 虽然没有 Mybatis 那么灵活，但是比直接使用 JDBC 要方便很多。SpringBoot 中对 JDBCTemplate 的使用提供了自动化配置类 JdbcTemplateAutoConfiguration，源码如下：

@Configuration(
        proxyBeanMethods = false
    )
    @ConditionalOnClass({ DataSource.class, JdbcTemplate.class})
    @ConditionalOnSingleCandidate(DataSource.class)
    @AutoConfigureAfter({ DataSourceAutoConfiguration.class})
    @EnableConfigurationProperties({ JdbcProperties.class})
    @Import({ JdbcTemplateConfiguration.class, NamedParameterJdbcTemplateConfiguration.class})
    public class JdbcTemplateAutoConfiguration { 
        public JdbcTemplateAutoConfiguration() { 
        }
    }

# 导入相关的依赖 #

<dependencies>
    
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
    
        
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
    
        
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
        </dependency>
    
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

# 创建数据库 #

创建数据库以及表比较简单，这里就不做描述了，有三个字段分别是 id、name、author

# 数据库配置 #

在 application.properties 文件中配置数据库基本的连接信息

spring:
      # 数据库配置
      datasource:
        url: jdbc:mysql://localhost:3306/数据库名?useSSL=false&useLegacyDatetimeCode=false&serverTimezone=UTC
        driver-class-name: com.mysql.cj.jdbc.Driver
        username: 用户名
        password: 密码
        initial-size: 10
        max-active: 20
        max-idle: 8
        min-idle: 8

# 创建实体类 #

package com.example.demo.entity;
    
    public class Book { 
        
        private Integer id;
        
        private String name;
        
        private String author;
    
        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 getAuthor() { 
            return author;
        }
    
        public void setAuthor(String author) { 
            this.author = author;
        }
    
        @Override
        public String toString() { 
            return "Book{" +
                    "id=" + id +
                    ", name='" + name + '\'' +
                    ", author='" + author + '\'' +
                    '}';
        }
    }

# 创建数据库访问层 #

代码如下：

package com.example.demo.dao;
    
    import com.example.demo.entity.Book;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.jdbc.core.BeanPropertyRowMapper;
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.stereotype.Repository;
    
    import java.util.List;
    
    @Repository
    public class BookDao { 
    
        // 注入 jdbc 模板
        @Autowired
        private JdbcTemplate jdbcTemplate;
    
        // 添加书信息
        public int addBook(Book book) { 
            return jdbcTemplate.update("INSERT INTO book(name,author) VALUES (?,?)",book.getName(),book.getAuthor());
        }
    
        // 修改书信息
        public int updateBook(Book book) { 
            return jdbcTemplate.update("UPDATE book SET name=?,author=? WHERE id = ?",book.getName(),book.getAuthor(),book.getId());
        }
    
        // 根据 id 删除书的信息
        public int deleteBookById(Integer id) { 
            return jdbcTemplate.update("DELETE FROM book WHERE id = ?",id);
        }
    
        // 根据 id 获取书的信息
        public Book getBookById(Integer id) { 
            return jdbcTemplate.queryForObject("SELECT * FROM book WHERE id = ?",new BeanPropertyRowMapper<>(Book.class),id);
        }
    
        // 查询所有书的信息
        public List<Book> getAllBooks() { 
            return jdbcTemplate.query("SELECT * FROM book",new BeanPropertyRowMapper<>(Book.class));
        }
    }

# 创建业务层 #

先创建一个业务接口 BookService

package com.example.demo.service;
    
    import com.example.demo.entity.Book;
    
    import java.util.List;
    
    public interface BookService { 
    
        // 添加书
        int addBook(Book book);
    
        // 修改书的信息
        int updateBook(Book book);
    
        // 删除书
        int deleteBookById(Integer id);
    
        // 根据 id 获取书
        Book getBookById(Integer id);
    
        // 查询所有书
        List<Book> getAllBooks();
    
    }

创建一个实现类实现该接口

package com.example.demo.service.impl;
    
    import com.example.demo.dao.BookDao;
    import com.example.demo.entity.Book;
    import com.example.demo.service.BookService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import java.util.List;
    
    @Service
    public class BookServiceImpl implements BookService { 
    
        @Autowired
        private BookDao bookDao;
    
        @Override
        public int addBook(Book book) { 
            return bookDao.addBook(book);
        }
    
        @Override
        public int updateBook(Book book) { 
            return bookDao.updateBook(book);
        }
    
        @Override
        public int deleteBookById(Integer id) { 
            return bookDao.deleteBookById(id);
        }
    
        @Override
        public Book getBookById(Integer id) { 
            return bookDao.getBookById(id);
        }
    
        @Override
        public List<Book> getAllBooks() { 
            return bookDao.getAllBooks();
        }
    }

# 控制器编写 #

以上代码编写好之后就可以编写控制器了，代码如下：

package com.example.demo.controller;
    
    import com.example.demo.entity.Book;
    import com.example.demo.service.BookService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    
    import java.util.List;
    
    @Controller
    public class BookController { 
    
        // 注入 BookService
        @Autowired
        private BookService bookService;
    
        @GetMapping("/bookOps")
        @ResponseBody
        public void bookOps() { 
            // 添加书信息
            Book book1 = new Book();
            book1.setName("西厢记");
            book1.setAuthor("王实甫");
            int addBook = bookService.addBook(book1);
            System.out.println("addBook --- " + addBook);
    
            // 修改书信息
            Book book2 = new Book();
            book2.setId(1);
            book2.setName("朝花夕拾");
            book2.setAuthor("鲁迅");
            int updateBook = bookService.updateBook(book2);
            System.out.println("updateBook --- " + updateBook);
    
            // 删除书信息
            int deleteBookById = bookService.deleteBookById(4);
            System.out.println("deleteBookById --- " + deleteBookById);
    
            // 根据 id 获取书信息
            Book getBookById = bookService.getBookById(1);
            System.out.println("getBookById --- " + getBookById);
    
            // 查询所以书信息
            List<Book> getAllBooks = bookService.getAllBooks();
            System.out.println("getAllBooks --- " + getAllBooks);
    
        }
    }

# 测试 #

我们运行一下项目，访问 http://localhost:8080/bookOps

![20200131230037117.png][]

然后查看数据库信息是否一致

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1dvb19ob21l_size_16_color_FFFFFF_t_70][]

OK，以上就是 SpringBoot 整合 JdbcTemplate 的例子

[SpringBoot]: https://blog.csdn.net/Woo_home/article/details/101925276
[SpringBoot 1]: https://blog.csdn.net/Woo_home/article/details/98860135
[SpringBoot 2]: https://blog.csdn.net/Woo_home/article/details/101981252
[20200131230037117.png]: https://img-blog.csdnimg.cn/20200131230037117.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1dvb19ob21l_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200131230128922.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1dvb19ob21l,size_16,color_FFFFFF,t_70