Spring Boot JdbcTemplate配置Druid多数据源

一、前言

JdbcTemplate配置Druid多数据源的核心在于创建JdbcTemplate时候为其分配不同的数据源，然后在需要访问不同数据库的时候使用对应的JdbcTemplate即可。这里介绍在Spring Boot中基于Oracle和Mysql配置Druid多数据源。

二、引入依赖

先根据《Spring Boot项目创建》应用，然后引入如下依赖：

xml 复制代码

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.22</version>
        </dependency>
        <dependency>
            <groupId>com.oracle</groupId>
            <artifactId>ojdbc6</artifactId>
            <version>6.0</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

三、多数据源配置

接着在Spring Boot配置文件application.yml中配置多数据源：

yml 复制代码

spring:
  datasource:
    druid:
      # 数据库访问配置, 使用druid数据源
      mysql:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/springboot?useUnicode=true&characterEncoding=utf8&serverTimezone=UTC&allowMultiQueries=true&useSSL=false
        username: spring
        password: spring#123
      oracle:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: oracle.jdbc.driver.OracleDriver
        url: jdbc:oracle:thin:@125.72.228.21:1521:qhfwbzdb
        username: wno704
        password: wno704db312
      # 连接池配置
      initial-size: 5
      min-idle: 5
      max-active: 20
      # 连接等待超时时间
      max-wait: 30000
      # 配置检测可以关闭的空闲连接间隔时间
      time-between-eviction-runs-millis: 60000
      # 配置连接在池中的最小生存时间
      min-evictable-idle-time-millis: 300000
      validation-query: select '1' from dual
      test-while-idle: true
      test-on-borrow: false
      test-on-return: false
      # 打开PSCache，并且指定每个连接上PSCache的大小
      pool-prepared-statements: true
      max-open-prepared-statements: 20
      max-pool-prepared-statement-per-connection-size: 20
      # 配置监控统计拦截的filters, 去掉后监控界面sql无法统计, 'wall'用于防火墙
      filters: stat,wall
      # Spring监控AOP切入点，如x.y.z.service.*,配置多个英文逗号分隔
      aop-patterns: com.wno704.boot.service.*
      # WebStatFilter配置
      web-stat-filter:
        enabled: true
        # 添加过滤规则
        url-pattern: /*
        # 忽略过滤的格式
        exclusions: '*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*'
      # StatViewServlet配置
      stat-view-servlet:
        enabled: true
        # 访问路径为/druid时，跳转到StatViewServlet
        url-pattern: /druid/*
        # 是否能够重置数据
        reset-enable: false
        # 需要账号密码才能访问控制台
        login-username: druid
        login-password: druid123
        # IP白名单
        # allow: 127.0.0.1
        #　IP黑名单（共同存在时，deny优先于allow）
        # deny: 192.168.1.218

      # 配置StatFilter
      filter:
        stat:
          log-slow-sql: true

然后创建一个多数据源配置类，根据application.yml分别配置一个Mysql和Oracle的数据源，并且将这两个数据源注入到两个不同的JdbcTemplate中：

java 复制代码

@Configuration
public class DataSourceConfig {
    @Primary
    @Bean(name = "mysqldatasource")
    @ConfigurationProperties("spring.datasource.druid.mysql")
    public DataSource dataSourceOne(){
        return DruidDataSourceBuilder.create().build();
    }

    @Bean(name = "oracledatasource")
    @ConfigurationProperties("spring.datasource.druid.oracle")
    public DataSource dataSourceTwo(){
        return DruidDataSourceBuilder.create().build();
    }

    @Bean(name = "mysqlJdbcTemplate")
    public JdbcTemplate primaryJdbcTemplate(
            @Qualifier("mysqldatasource") DataSource dataSource) {
        return new JdbcTemplate(dataSource);
    }

    @Bean(name = "oracleJdbcTemplate")
    public JdbcTemplate secondaryJdbcTemplate(
            @Qualifier("oracledatasource") DataSource dataSource) {
        return new JdbcTemplate(dataSource);
    }
}

上述代码根据application.yml创建了mysqldatasource和oracledatasource数据源，其中mysqldatasource用@Primary标注为主数据源，接着根据这两个数据源创建了mysqlJdbcTemplate和oracleJdbcTemplate。

@Primary标志这个Bean如果在多个同类Bean候选时，该Bean优先被考虑。多数据源配置的时候，必须要有一个主数据源，用@Primary标志该Bean。

数据源创建完毕，接下来开始进行测试代码编写。

四、编码

首先往Mysql和Oracle中创建测试表，并插入一些测试数据：

Mysql：

sql 复制代码

drop table if exists `student`;
create table `student`  (
  `sno` int(11) not null auto_increment comment '学号',
  `sname`  varchar(50) character set utf8 collate utf8_general_ci not null comment '姓名',
  `ssex` varchar(2) character set utf8 collate utf8_general_ci not null comment '性别',
	primary key (`sno`) using btree
) engine = innodb auto_increment = 1 character set = utf8 collate = utf8_general_ci row_format = dynamic;

insert into `student` values (1, 'KangKang', 'M');
insert into `student` values (2, 'Mike', 'M');
insert into `student` values (3, 'Jane', 'F');

Oracle:

xml 复制代码

    CREATE TABLE "WNO704"."STUDENT" (
    "SNO" NUMBER NOT NULL,
    "SNAME" NVARCHAR2(50),
    "SSEX" NVARCHAR2 (2),
    CONSTRAINT "PK_STUDENT_SNO" PRIMARY KEY ("SNO")
    )
    tablespace WNO704
    	PCTFREE 10
    	initrans 1
    	maxtrans 255 storage (
    		INITIAL 768K
    		next 8K
    		minextents 1
    		MAXEXTENTS unlimited t 8K
    		minextents 1
    		MAXEXTENTS unlimited
    );

    COMMENT ON COLUMN "WNO704"."STUDENT"."SNO" IS '学号';
    COMMENT ON COLUMN "WNO704"."STUDENT"."SNAME" IS '姓名';
    COMMENT ON COLUMN "WNO704"."STUDENT"."SSEX" IS '性别';

    INSERT INTO "STUDENT" VALUES (1, 'KangKang', 'M');
    INSERT INTO "STUDENT" VALUES (2, 'Mike', 'M');
    INSERT INTO "STUDENT" VALUES (3, 'Jane', 'F');

MysqlStudentDao接口：

java 复制代码

public interface MysqlStudentDao {
    List<Map<String, Object>> getAllStudents();
}

MysqlStudentDao实现；

java 复制代码

@Repository
public class MysqlStudentDaoImpl implements MysqlStudentDao {
    @Autowired
    @Qualifier("mysqlJdbcTemplate")
    private JdbcTemplate jdbcTemplate;

    @Override
    public List<Map<String, Object>> getAllStudents() {
        return this.jdbcTemplate.queryForList("select * from student");
    }
}

可看到，在MysqlStudentDaoImp中注入的是mysqlJdbcTemplate。

OracleStudentDao接口：

java 复制代码

public interface OracleStudentDao {
    List<Map<String, Object>> getAllStudents();
}

OracleStudentDao实现：

java 复制代码

@Repository
public class OracleStudentDaoImpl implements OracleStudentDao {
    @Autowired
    @Qualifier("oracleJdbcTemplate")
    private JdbcTemplate jdbcTemplate;

    @Override
    public List<Map<String, Object>> getAllStudents() {
        return this.jdbcTemplate.queryForList("select * from student");
    }
}

在OracleStudentDaoImp中注入的是oracleJdbcTemplate。

随后编写Service层：

StudentService接口：

java 复制代码

public interface StudentService {
    List<Map<String, Object>> getAllStudentsWithMysql();
    List<Map<String, Object>> getAllStudentsWithOracle();
}

StudentService实现：

java 复制代码

@Service("studentService")
public class StudentServiceImpl implements StudentService {

    @Autowired
    private OracleStudentDao oracleStudentDao;

    @Autowired
    private MysqlStudentDao mysqlStudentDao;

    @Override
    public List<Map<String, Object>> getAllStudentsWithMysql() {
        return this.mysqlStudentDao.getAllStudents();
    }

    @Override
    public List<Map<String, Object>> getAllStudentsWithOracle() {
        return this.oracleStudentDao.getAllStudents();
    }
}

五、测试

最后编写TestController：

java 复制代码

@RestController
public class TestController {
    @Autowired
    private StudentService studentService;

    @RequestMapping( value = "/getAllStudentsWithMysql", method = RequestMethod.GET)
    public List<Map<String, Object>> getAllStudentsWithMysql() {
        return this.studentService.getAllStudentsWithMysql();
    }

    @RequestMapping( value = "/getAllStudentsWithOracle", method = RequestMethod.GET)
    public List<Map<String, Object>> getAllStudentsWithOracle() {
        return this.studentService.getAllStudentsWithOracle();
    }
}

最终项目目录如下图所示：

启动项目，访问：http://localhost:8080/getAllStudentsWithMysql

http://localhost:8080/getAllStudentsWithOracle