Failed to load driver class com.mysql.jdbc.Driver

In my case the next dependency was missing:

<dependency>
     <groupId>mysql</groupId>
     <artifactId>mysql-connector-java</artifactId>
</dependency>

In case of using IntelliJ and if you inherit from a <parent>, you can view your effective pom.xml by right clicking anywhere inside your pom.xml, then:

and search for the mysql-connector-java artifact as mentioned.

The answer is so embarrassing. I appended the driver line of application.properties with a semicolon …
Obviously, it did’t recognize that driver.

just add mysql and jdbc dependencies like below

    <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>

I had a problem where I was using Spring Boot 2.2.0.RELEASE and needed to connect to an old Mysql DB (5.1.73), which required me to downgrade to mysql-connector-java version 5.1.38

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.38</version>
    </dependency>

Since Spring boot was expecting a newer mysql-java-connector, which has been renamed to com.mysql.cj.jdbc.Driver, I also had to add the spring datasource driver-class-name setting in my spring boot db config.

So my spring boot config ended up like this:

spring:
  datasource:
   url: 'localhost'
   password: password
   username: user
   driver-class-name: com.mysql.jdbc.Driver