java spring 连接 mysql 数据库

源码下载

在mysql数据库创建表CUSTOMER

CREATE TABLE CUSTOMER(CUST_ID  INT(11),
              NAME VARCHAR(60),
              AGE INT(11),
              PRIMARY KEY (`CUST_ID`)
              );

插入示例数据

   INSERT INTO CUSTOMER VALUES(1,'Toomi',23);

在eclipse新建maven project

File --> New --> Maven Project
- archetype: maven-archetype-quickstart
- Group Id: come.best
- Artifact Id: MyJdbcApp
- 其他默认

在pom.xml添加如下依赖

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.9</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>4.0.5.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>4.0.5.RELEASE</version>
    </dependency>

建立domain层customer对象

1. src/main/java下创建跑package,名为 com.best.domain
2. 在上一步创建的package下创建一个class,名为Customer

内容如下：

package com.best.domain;

public class Customer {
    int custId;
    String name;
    int age;
    
    public Customer() {
        super();
    }
    
    public Customer(int custId, String name, int age) {
        this.custId = custId;
        this.name = name;
        this.age = age;
    }

    public int getCustId() {
        return custId;
    }

    public void setCustId(int custId) {
        this.custId = custId;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Customer [age=" + age + ", custId=" + custId + ", name=" + name + "]";
    }

}

创建repository层CustomerRepository接口

1. src/main/java下创建跑package,名为 com.best.domain.repository
2. 在上一步创建的package下创建一个interface,名为CustomerRepository

内容如下：

    package com.best.domain.repository;
    import com.best.domain.Customer;;
    
    public interface CustomerRepository {
        public Customer find(int cust_id);
    }

实现repository层CustomerRepository接口

1. src/main/java下创建跑package,名为 com.best.domain.repository.impl
2. 在上一步创建的package下创建一个class,名为CustomerRepositoryImpl

内容如下：

    package com.best.domain.repository.impl;
    
    import com.best.domain.Customer;
    import com.best.domain.repository.*;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.jdbc.core.RowMapper;
    
    public class CustomerRepositoryImpl implements CustomerRepository {
        private JdbcTemplate jdbcTemplate;
    
        public JdbcTemplate getJdbcTemplate() {
            return jdbcTemplate;
        }
    
        private static final class CustomerRowMapper implements RowMapper<Customer> {
            public Customer mapRow(ResultSet rs, int rowNum) throws SQLException {
                Customer customer = new Customer(rs.getInt("CUST_ID"), rs.getString("NAME"), rs.getInt("Age"));
                return customer;
            }
        }
    
        public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
            this.jdbcTemplate = jdbcTemplate;
        }
    
        public Customer find(int cust_id) {
    
            return jdbcTemplate.queryForObject("SELECT CUST_ID,NAME,AGE FROM CUSTOMER WHERE CUST_ID = ?",
                    new CustomerRowMapper(), cust_id);
        }
    }

配置dataSource以及JdbcTemplate

1. src/main/java下创建跑package,名为 com.best.config
2. 在上一步创建的package下创建一个class,名为SpringJdbcConfig

内容为：

    package com.best.config;
    
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.Bean;
    import org.springframework.jdbc.datasource.DriverManagerDataSource;
    import org.springframework.jdbc.core.JdbcTemplate;
    import javax.sql.DataSource;
    import com.best.domain.repository.*;
    import com.best.domain.repository.impl.CustomerRepositoryImpl;
    
    @Configuration
    public class SpringJdbcConfig {
        @Bean
        public DataSource dataSource() {
            DriverManagerDataSource dataSource = new DriverManagerDataSource();
            dataSource.setDriverClassName("com.mysql.jdbc.Driver");
            dataSource.setUrl("jdbc:mysql://localhost:3306/toomi");
            dataSource.setUsername("toomi");
            dataSource.setPassword("toomi");
    
            return dataSource;
        }
    
        @Bean
        public JdbcTemplate jdbcTemplate() {
            JdbcTemplate jdbcTemplate = new JdbcTemplate();
            jdbcTemplate.setDataSource(dataSource());
            return jdbcTemplate;
        }
    
        @Bean
        public CustomerRepository customerRepository() {
            CustomerRepositoryImpl customerRepository = new CustomerRepositoryImpl();
            customerRepository.setJdbcTemplate(jdbcTemplate());
            return customerRepository;
    
        }
    }

修改程序入口 App.java

将package com.best.MyJdbcApp下App.java文件内容修改如下

    package com.best.MyJdbcApp;
    
    import java.sql.SQLException;
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    import com.best.config.SpringJdbcConfig;
    import com.best.domain.Customer;
    import com.best.domain.repository.CustomerRepository;
    
    public class App {
        public static void main(String[] args) throws SQLException {
            AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(
                    SpringJdbcConfig.class);
            CustomerRepository customerRepository = applicationContext.getBean(CustomerRepository.class);
            Customer customer = customerRepository.find(1);
            System.out.print(customer.getAge());
            //applicationContext.close();
        }
    }

运行程序

选中 App.java --> 右键 Run As --> Java Application
将会在控制台看见 输出数字23，即toomi的年龄

参考链接

• Spring + JDBC example
• Spring JDBC
• MySQL Java tutorial