1.问题：

java.lang.IllegalStateException: dbType not support : null, url null
    at com.alibaba.druid.wall.WallFilter.init(WallFilter.java:159) ~[druid-1.1.5.jar:1.1.5]
    at com.alibaba.druid.pool.DruidDataSource.init(DruidDataSource.java:770) [druid-1.1.5.jar:1.1.5]
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1215) [druid-1.1.5.jar:1.1.5]
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1211) [druid-1.1.5.jar:1.1.5]
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:105) [druid-1.1.5.jar:1.1.5]
    at

2.原因：
报错原因就是因为在DataSourceConfig中使用了

 1 @Configuration
 2 public class DataSourceConfig {
 3 
 4     @Bean(name = "primaryDataSource")
 5     @Qualifier("primaryDataSource")
 6     @Primary
 7     @ConfigurationProperties(prefix = "spring.datasource.primary")
 8     public DataSource primaryDatasource() {
 9         return DataSourceBuilder.create().type(==com.alibaba.druid.pool.DruidDataSource.class==).build();
10     }
11 
12     @Bean(name = "secondaryDataSource")
13     @Qualifier("secondaryDataSource")
14     @ConfigurationProperties(prefix = "spring.datasource.secondary")
15     public DataSource secondaryDataSource() {
16         return DataSourceBuilder.create().type(==com.alibaba.druid.pool.DruidDataSource.class==).build();
17     }
18 }

3.问题展示：
而在application.yml配置文件中使用了jdbc-url从而产生了错误，原有配置：

spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    primary:
      driver-class-name: com.mysql.cj.jdbc.Driver
      #jdbc-url: jdbc:mysql://localhost/test1?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC&useSSL=false
      url: jdbc:mysql://localhost/test1?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC&useSSL=false
      username: root
      password: 123456
      # 下面为连接池的补充设置，应用到上面所有数据源中
      # 初始化大小，最小，最大
      name: primary
      initialSize: 5
      minIdle: 5
      maxActive: 20
      # 配置获取连接等待超时的时间
      maxWait: 60000
      # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
      timeBetweenEvictionRunsMillis: 60000
      # 配置一个连接在池中最小生存的时间，单位是毫秒
      minEvictableIdleTimeMillis: 300000
      validationQuery: SELECT 1
      testWhileIdle: true
      testOnBorrow: false
      testOnReturn: false
      # 打开PSCache，并且指定每个连接上PSCache的大小
      poolPreparedStatements: true
      maxPoolPreparedStatementPerConnectionSize: 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,log4j
      # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      logSlowSql: true
      # 合并多个DruidDataSource的监控数据
      useGlobalDataSourceStat: true
    secondary:
      driver-class-name: com.mysql.cj.jdbc.Driver
      #jdbc-url: jdbc:mysql://localhost/test2?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC&useSSL=false
      url: jdbc:mysql://localhost/test2?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC&useSSL=false
      username: root
      password: 123456
      # 下面为连接池的补充设置，应用到上面所有数据源中
      # 初始化大小，最小，最大
      name: secondary
      initialSize: 5
      minIdle: 5
      maxActive: 20
      # 配置获取连接等待超时的时间
      maxWait: 60000
      # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
      timeBetweenEvictionRunsMillis: 60000
      # 配置一个连接在池中最小生存的时间，单位是毫秒
      minEvictableIdleTimeMillis: 300000
      validationQuery: SELECT 1
      testWhileIdle: true
      testOnBorrow: false
      testOnReturn: false
      # 打开PSCache，并且指定每个连接上PSCache的大小
      poolPreparedStatements: true
      maxPoolPreparedStatementPerConnectionSize: 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,log4j
      # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      logSlowSql: true
      # 合并多个DruidDataSource的监控数据
      useGlobalDataSourceStat: true

4.解决方法:
　将application.yml 配置文件中的jdbc-url改成url就行了