Spring Boot 自定义数据源DruidDataSource代码

那么关于Spring Boot自定义数据源DruidDataSource的完整攻略，主要分为以下几个步骤：

1. 导入相关依赖

首先，在Spring Boot项目中，需要导入Druid和JDBC相关的依赖。可以在pom.xml文件中加入如下代码：

<!-- 导入Druid数据源依赖 -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.2.6</version>
</dependency>

<!-- 导入JDBC依赖 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-jdbc</artifactId>
    <version>2.4.3</version>
</dependency>

1. 配置Druid数据源

其次，我们需要在application.properties或application.yml文件中配置Druid数据源。可配置的项如下：

spring.datasource.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=root

#Druid参数配置
spring.datasource.druid.initial-size=5
spring.datasource.druid.min-idle=5
spring.datasource.druid.max-active=20
spring.datasource.druid.max-wait=60000
spring.datasource.druid.test-while-idle=true
spring.datasource.druid.test-on-borrow=false
spring.datasource.druid.test-on-return=false
spring.datasource.druid.pool-prepared-statements=true
spring.datasource.druid.max-pool-prepared-statement-per-connection-size=20
spring.datasource.druid.log-slow-sql=true
spring.datasource.druid.allow=true
spring.datasource.druid.remove-abandoned=true
spring.datasource.druid.remove-abandoned-timeout=1800

1. 提供自定义Druid数据源

接着，我们需要定义一个类，该类继承AbstractRoutingDataSource抽象类，用于切换不同的数据源。示例代码如下：

public class DynamicDataSource extends AbstractRoutingDataSource {

    public static final ThreadLocal<String> contextHolder = new ThreadLocal<>();

    @Override
    protected Object determineCurrentLookupKey() {
        return getDataSource();
    }

    public static void setDataSource(String dataSource) {
        contextHolder.set(dataSource);
    }

    public static String getDataSource() {
        return contextHolder.get();
    }

    public static void clearDataSource() {
        contextHolder.remove();
    }

}

1. 配置自定义的数据源

最后，我们需要在Spring Boot的配置文件中设置我们刚才定义的数据源：

@Configuration
public class DataSourceConfig {

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.druid")
    public DruidDataSource dataSource() {
        return new DruidDataSource();
    }

    @Bean(name = "dataSourceProxy")
    public DataSource dataSourceProxy() {
        Map<Object, Object> targetDataSources = new HashMap<>();
        DruidDataSource dataSource = dataSource();
        targetDataSources.put("dataSource", dataSource);
        DynamicDataSource dataSourceProxy = new DynamicDataSource();
        dataSourceProxy.setTargetDataSources(targetDataSources);
        dataSourceProxy.setDefaultTargetDataSource(dataSource);
        return dataSourceProxy;
    }

    @Bean
    public JdbcTemplate jdbcTemplate(DataSource dataSourceProxy) {
        return new JdbcTemplate(dataSourceProxy);
    }
}

至此，我们结束了整个自定义数据源DruidDataSource的配置过程。

下面是两个示例：

1. 示例一：切换数据源

@Service
public class UserService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    public void addUser(User user) {
        String sql = "insert into user(id, name, age) values(?, ?, ?)";
        Object[] params = new Object[] {user.getId(), user.getName(), user.getAge()};
        int count = jdbcTemplate.update(sql, params);
        System.out.println("新增用户数：" + count);
    }

    public void findAll() {
        DynamicDataSource.setDataSource("dataSource2");
        String sql = "select * from user";
        List<User> userList = jdbcTemplate.query(sql, new BeanPropertyRowMapper(User.class));
        System.out.println("查询结果：" + userList);
        DynamicDataSource.clearDataSource();
    }
}

1. 示例二：手动配置数据源

@Configuration
public class DataSourceConfig {

    @Bean
    public DataSource dataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setUrl("jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai");
        dataSource.setUsername("root");
        dataSource.setPassword("root");
        dataSource.setInitialSize(5);
        dataSource.setMinIdle(5);
        dataSource.setMaxActive(20);
        dataSource.setMaxWait(60000);
        dataSource.setTestWhileIdle(true);
        dataSource.setTestOnBorrow(false);
        dataSource.setTestOnReturn(false);
        dataSource.setPoolPreparedStatements(true);
        dataSource.setMaxPoolPreparedStatementPerConnectionSize(20);
        dataSource.setLogSlowSql(true);
        return dataSource;
    }

    @Bean(name = "dataSourceProxy")
    public DataSource dataSourceProxy() {
        Map<Object, Object> targetDataSources = new HashMap<>();
        DruidDataSource dataSource = (DruidDataSource) dataSource();
        targetDataSources.put("dataSource", dataSource);
        DynamicDataSource dataSourceProxy = new DynamicDataSource();
        dataSourceProxy.setTargetDataSources(targetDataSources);
        dataSourceProxy.setDefaultTargetDataSource(dataSource);
        return dataSourceProxy;
    }

    @Bean
    public JdbcTemplate jdbcTemplate(DataSource dataSourceProxy) {
        return new JdbcTemplate(dataSourceProxy);
    }
}

以上就是对Spring Boot自定义数据源DruidDataSource的完整攻略和示例讲解。