@Configuration
public class SpringConfig {
    @Bean
    @Singleton
    public DataSource getDataSource() {
        BasicDataSource basicDataSource = new BasicDataSource();
        basicDataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");
        basicDataSource.setUrl("jdbc:mysql://localhost:3306/db?serverTimezone=UTC");
        basicDataSource.setUsername("name");
        basicDataSource.setPassword("password");
        basicDataSource.setInitialSize(5);
        basicDataSource.setMinIdle(3);
        basicDataSource.setMaxIdle(15);
        basicDataSource.setMaxWait(10000);
        basicDataSource.setMaxActive(100);
        return basicDataSource;
    }
}

@Configuration
@PropertySource("classpath:database.properties")
public class SpringConfig {
    private @Value("${propertyName}") String propertyField;

    @Bean
    @Singleton
    public DataSource getDataSource() {
        BasicDataSource basicDataSource = new BasicDataSource();basicDataSource.setConnectionProperties(propertyField);
        return basicDataSource;
    }
}

driverClassName = "com.mysql.cj.jdbc.Driver"
url="jdbc:mysql://localhost:3306/db"
username="user"
password="password"