场景:利用springboot整合druid数据源主要是可以对多次连接数据库中的连接起到反复利用的效果,性能也是最好的,同时还能提供监控的功能,是在前面的代码之上改造过来的,同时我们也用druid来搭配多数据源来使用:
流程: 导入pom包, 配置好文件, 编写配置类, controller层访问:
pom包的导入:这次只是添加一个druid包

<dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>

配置文件的编写: 注意配置文件中路径

server:
  port: 9089

spring:
  datasource:
    master:
      # class name
      driver-class-name: com.mysql.cj.jdbc.Driver
      #springboot默认的连接池
      type: com.alibaba.druid.pool.DruidDataSource
      #规定写jdbcUrl路径
      url: jdbc:mysql://127.0.0.1:3306/springboot?useSSL=false&serverTimezone=UTC
      username: root
      password: 123456
      initial-size: 5 #初始化的个数
      min-idle: 5 #空闲时的最小个数
      max-idle: 20
      max-wait: 60000 #配置获取连接等待超时时间
      pool-prepared-statements: false #是否启用PScach  对于oracle数据库
      max-open-prepared-statements: 0 # 要想启用PScach,这个属性值必须大于0
      time-between-evition-runs-mills: 60000 #配置间隔多久进行一次检测,检测需要关闭的时间
      min-evictable-idle-time-mills: 30000 #连接池中最小与最大的生存时间
      max-evictable-idle-time-mills: 90000 #连接池中最大的生存时间
      test-while-idle: true #申请链接的时候监测,如果空闲时间大于timeBeween,执行校验
      test-on-return: true # 归还链接时,执行校验sql
      test-on-borrow: true  #申请链接时执行校验sql
      validation-query: SELECT 1
      filters: stat #stat用于统计  wall是用来防火墙
    slave:
      driver-class-name: com.mysql.cj.jdbc.Driver
      type: com.alibaba.druid.pool.DruidDataSource
      jdbcUrl: jdbc:mysql://127.0.0.1:3306/learn?useSSL=false&serverTimezone=UTC
      username: root
      password: 123456
      initial-size: 5 #初始化的个数
      min-idle: 5 #空闲时的最小个数
      max-idle: 20
      max-wait: 60000 #配置获取连接等待超时时间
      pool-prepared-statements: false #是否启用PScach  对于oracle数据库
      max-open-prepared-statements: 0 # 要想启用PScach,这个属性值必须大于0
      time-between-evition-runs-mills: 60000 #配置间隔多久进行一次检测,检测需要关闭的时间
      min-evictable-idle-time-mills: 30000 #连接池中最小与最大的生存时间
      max-evictable-idle-time-mills: 90000 #连接池中最大的生存时间
      test-while-idle: true #申请链接的时候监测,如果空闲时间大于timeBeween,执行校验
      test-on-return: true # 归还链接时,执行校验sql
      test-on-borrow: true  #申请链接时执行校验sql
      validation-query: SELECT 1
      filters: stat  #stat用于统计  wall是用来防火墙

  redis:
    database: 0
    host: localhost
    port: 6379
    password:
    pool:
      max-active: 200
      max-wait: -1
      max-idle: 10
      min-idle: 0 #最小空闲数
    timeout: 1000


# pagehelper
pagehelper:
  helperDialect: mysql  #支持mysql
  reasonable: true      #合理化,小于0既查询第一页,大于就查询最后一页
  supportMethodsArguments: true   #是否允许通过mapper接口传递参数
  params: count=countSql    #总页数为countSql
/**
 * @Author: Jason
 * @Create: 2020/11/18  21:47
 * @Description  配置了多个数据源
 */

@SpringBootConfiguration
@MapperScan("com.example.demo.dao")
public class MybatiesConfig {

    /**
     * 定义一个默认的数据库
     * 从配置文件中直接拿取配置好的主数据库配置
     * @return
     */
    @Bean("master")
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource.master")
    public DataSource master(){
        return new DruidDataSource();
    }


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

    /**
     * 配置动态数据源类
     * @return
     * @throws Exception
     */
    @Bean("dynamicDataSource")
    public DataSource dynamicDataSource() throws Exception {
        DynamicDataSource sqlSessionFactoryBean = new DynamicDataSource();
        Map<Object, Object> dataSourceMap = new HashMap<>();
        //将配置好的数据源添加到动态数据源中去
        dataSourceMap.put("master", master());
        dataSourceMap.put("slave", slave());
        //指定默认的数据源
        sqlSessionFactoryBean.setDefaultDataSource(master());
        //将已经配置好的类添加
        sqlSessionFactoryBean.setDataSources(dataSourceMap);
        return sqlSessionFactoryBean;
    }

    /**
     * 创建一个sqlSessionFactory类
     * @return
     * @throws Exception
     */
    @Bean
    public SqlSessionFactoryBean sqlSessionFactoryBean() throws Exception {
        SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
        //设置好动态数据类
        sessionFactory.setDataSource(dynamicDataSource());
        sessionFactory.setTypeAliasesPackage("com.example.demo.model");
        //扫描到xml位置的并且注入到工厂中去
        PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        sessionFactory.setMapperLocations(resolver.getResources("classpath*:**/sqlmap/*.xml"));
        return sessionFactory;
    }

    /**
     * 对动态数据源开启事务管理
     * @return
     * @throws Exception
     */
    @Bean
    public PlatformTransactionManager platformTransactionManager() throws Exception {
        return new DataSourceTransactionManager(dynamicDataSource());
    }

    /**
     * 配置一个Druid的监控
     * 配置一个管理后台的Servlet
     * @return
     */
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
        Map<String, String> initParams = new HashMap<>();

        initParams.put("loginUsername", "admin");
        initParams.put("loginPassword", "123456");
        initParams.put("allow", ""); //默认就是允许所有的访问
        initParams.put("deny", "");

        bean.setInitParameters(initParams);
        return bean;
    }


    /**
     * 这是设置一个filter类
     * @return
     */
    @Bean
    public FilterRegistrationBean webStatFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());
        Map<String, String> initParams = new HashMap<>();
        initParams.put("exclutions", "*.js, *.css, /druid/*");
        bean.setUrlPatterns(Arrays.asList("/*"));
        bean.setInitParameters(initParams);
        return bean;
    }
}
/**
• @Author: Jason
• @Create: 2020/11/18 21:47
• @Description 配置了多个数据源
 */@SpringBootConfiguration
 @MapperScan(“com.example.demo.dao”)
 public class MybatiesConfig {
/**
 * 定义一个默认的数据库
 * 从配置文件中直接拿取配置好的主数据库配置
 * @return
 */
@Bean("master")
@Primary
@ConfigurationProperties(prefix = "spring.datasource.master")
public DataSource master(){
    return new DruidDataSource();
}


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

/**
 * 配置动态数据源类
 * @return
 * @throws Exception
 */
@Bean("dynamicDataSource")
public DataSource dynamicDataSource() throws Exception {
    DynamicDataSource sqlSessionFactoryBean = new DynamicDataSource();
    Map<Object, Object> dataSourceMap = new HashMap<>();
    //将配置好的数据源添加到动态数据源中去
    dataSourceMap.put("master", master());
    dataSourceMap.put("slave", slave());
    //指定默认的数据源
    sqlSessionFactoryBean.setDefaultDataSource(master());
    //将已经配置好的类添加
    sqlSessionFactoryBean.setDataSources(dataSourceMap);
    return sqlSessionFactoryBean;
}

/**
 * 创建一个sqlSessionFactory类
 * @return
 * @throws Exception
 */
@Bean
public SqlSessionFactoryBean sqlSessionFactoryBean() throws Exception {
    SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
    //设置好动态数据类
    sessionFactory.setDataSource(dynamicDataSource());
    sessionFactory.setTypeAliasesPackage("com.example.demo.model");
    //扫描到xml位置的并且注入到工厂中去
    PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
    sessionFactory.setMapperLocations(resolver.getResources("classpath*:**/sqlmap/*.xml"));
    return sessionFactory;
}

/**
 * 对动态数据源开启事务管理
 * @return
 * @throws Exception
 */
@Bean
public PlatformTransactionManager platformTransactionManager() throws Exception {
    return new DataSourceTransactionManager(dynamicDataSource());
}

/**
 * 配置一个Druid的监控
 * 配置一个管理后台的Servlet
 * @return
 */
@Bean
public ServletRegistrationBean statViewServlet(){
    ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
    Map<String, String> initParams = new HashMap<>();

    initParams.put("loginUsername", "admin");
    initParams.put("loginPassword", "123456");
    initParams.put("allow", ""); //默认就是允许所有的访问
    initParams.put("deny", "");

    bean.setInitParameters(initParams);
    return bean;
}


/**
 * 这是设置一个filter类
 * @return
 */
@Bean
public FilterRegistrationBean webStatFilter(){
    FilterRegistrationBean bean = new FilterRegistrationBean();
    bean.setFilter(new WebStatFilter());
    Map<String, String> initParams = new HashMap<>();
    initParams.put("exclutions", "*.js, *.css, /druid/*");
    bean.setUrlPatterns(Arrays.asList("/*"));
    bean.setInitParameters(initParams);
    return bean;
}