<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-data-rest</artifactId>
        </dependency>

        <dependency>
          <groupId>org.activiti</groupId>
          <artifactId>spring-boot-starter-jpa</artifactId>
          <version>RELEASE</version>
        </dependency>

        <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
          <version>RELEASE</version>
          <scope>runtime</scope>
        </dependency>
</dependencies>

package prueba;

import org.springframework.data.jpa.repository.JpaRepository;

public interface RepositorioUsuariosDB extends JpaRepository<Usuario, Long> {

}

package prueba;

import javax.persistence.Entity;
import javax.persistence.Id;

@Entity
public class Usuario {
 @Id
 private Long id;
 private String nombre;
 private String password;

 public Usuario() {}

 public Usuario(String nombre, String password ) {
     this.nombre = nombre;
     this.password = password;
 }

 public Long getId() {
     return id;
 }

 public void setId(Long id) {
     this.id = id;
 }

 public String getNombre() {
     return nombre;
 }

 public void setNombre(String nombre) {
     this.nombre = nombre;
 }


 public String getPassword() {
     return password;
 }

 public void setPassword(String password) {
     this.password = password;
 }

 @Override
 public String toString() {
     return "Usuario{" +
             "id=" + id +
             ", nombre='" + nombre + '''+
             '}';
 }
}

spring.datasource.url= jdbc:mysql://localhost:8080/localservice?useSSL=false
spring.datasource.username= miname
spring.datasource.password= mipass
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.jpa.database-platform=org.hibernate.dialect.MySQL5InnoDBDialect
logging.level.org.hibernate.SQL=debug

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
    2018-06-29 10:24:11.781 ERROR 9376 --- [           main] o.s.boot.SpringApplication               : Application startup failed

    org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Tomcat.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver
        at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:749) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:189) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1193) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1095) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
____________
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Tomcat.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver
__________________
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.tomcat.jdbc.pool.DataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
    ... 41 common frames omitted
Caused by: java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver

http://ledze.mx/index.php/10-spring-boot/restful/12-spring-boot-datarest-conexion-con-mysql-y-manejo-con-jpa