spring.datasource.test-while-idle=true
spring.datasource.validation-interval=5000

cloud.aws.rds.testdb.password=testdbpwd
cloud.aws.rds.testdb.username=testdbuser
cloud.aws.rds.testdb.databaseName=testdb

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.test-on-borrow: true
spring.datasource.validation-query: SELECT 1 FROM DUAL
spring.datasource.log-validation-errors: true

@Component
public class PoolConfiguration implements BeanPostProcessor {

@Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
    if (bean instanceof TomcatJdbcDataSourceFactory) {
        TomcatJdbcDataSourceFactory tomcatJdbcDataSourceFactory = (TomcatJdbcDataSourceFactory) bean;
        tomcatJdbcDataSourceFactory.setTestOnBorrow(true);
        tomcatJdbcDataSourceFactory.setTestWhileIdle(true);
        tomcatJdbcDataSourceFactory.setValidationQuery("SELECT 1");
    }
    return bean;
}
}