Failed to bind properties under ‘spring.datasource‘ to javax.sql.DataSource:

1.springboot在整合druid时，首先需要在yml配置文件中加入druid的相关配置

spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource


    #SpringBoot默认是不注入这些的，需要自己绑定
    #druid数据源专有配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECt 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true

    #配置监控统计拦截的filters，stat：监控统计、log4j：日志记录、wall：防御sql注入
    #如果允许报错，java.lang.ClassNotFoundException: org.apache.Log4j.Properity
    #则导入log4j 依赖就行
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionoProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500

2.进行druid相关的配置类的编写

@Configuration
public class DruidConfig {

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

    // 后台监控：相当于web.xml，配置ServletRegistrationBean
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean bean = new ServletRegistrationBean<>(new StatViewServlet(), "/druid/*");

        // 后台登录进行账号密码配置
        HashMap initParameters = new HashMap<>();

        // 增加配置，登录的key是固定的，loginUsername  loginPassword
        initParameters.put("loginUsername","admin");
        initParameters.put("loginPassword","123456");

        // 允许谁可以访问，如果后面的参数为空代表谁都可以访问，指定参数只能指定的参数进行访问
        initParameters.put("allow","");

        // 禁止谁可以访问
//        initParameters.put("koko","192.168.43.21");


        bean.setInitParameters(initParameters); // 设置初始化参数
        return bean;
    }

// filter
    @Bean
    public FilterRegistrationBean webStatFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());
        // 可以过滤的请求
        HashMap initParameters = new HashMap<>();
        // 以下不进行统计
        initParameters.put("exclusions","*.js,*.css,/druid/*");
        bean.setInitParameters(initParameters);
        return bean;
    }
}

3.启动项目，然后被发现无法启动，会报这样一个错

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to bind properties under 'spring.datasource' to javax.sql.DataSource:

    Property: spring.datasource.filters
    Value: stat,wall,log4j
    Origin: class path resource [application.yml]:27:14
    Reason: org.apache.log4j.Logger

Action:

Update your application's configuration

4. 根据错误的指示原因，可以发现是没有导入log4j的依赖

        
        
            log4j
            log4j
            1.2.17
        

5. 项目启动成功，可以进入druid的登录界面

6.在配置中设置的用户名和密码进行登录