jdbc.driverClassName=com.mysql.jdbc.Driver

jdbc.url=jdbc:mysql://lcoalhost:3306/shop

jdbc.userName=root

jdbc.password=12345

@ConfigurationProperties(prefix = "jdbc")

@Data

public class JdbcProperties {

    String driverClassName;

    String url;

    String userName;

    String password;

}

//标记为一个配置类 代替xml文件

@Configuration
//拿到属性

@EnableConfigurationProperties(JdbcProperties.class)

public class JdbcConfig {

    @Bean

    //将返回值加入bean容器 代替<bean>标签

    public DataSource dataSource(JdbcProperties prop) {

        DruidDataSource dataSource = new DruidDataSource();

        dataSource.setDriverClassName(prop.getDriverClassName());

        dataSource.setUrl(prop.getUrl());

        dataSource.setUsername(prop.getUserName());

        dataSource.setPassword(prop.getPassword());

        return dataSource;

    }

}

@Configuration

public class JdbcConfig {

    @Bean

    @ConfigurationProperties(prefix = "jdbc")

    /**@ConfigurationProperties

     * 把配置文件的信息，读取并自动封装成实体类

     * @ConfigurationProperties还可以直接定义在@bean的注解上，这是bean实体类就不用@Component和@ConfigurationProperties

     */

    public DataSource dataSource() {

        DruidDataSource dataSource = new DruidDataSource();

        return dataSource;

    }

}