spring-boot-2-7-x-circular-reference-example

Example project reproducing circular reference error in Spring Boot with dependencies spring-boot-starter-data-jpa and spring-boot-starter-actuator with tested versions 2.7.10 and 2.7.11 when upgrading from version 2.6.13.

When injecting a RestTemplateBuilder or RestTemplate class instance to either a Configuration class constructor with a getDataSource Bean or directly to the getDataSource Bean method a circular reference error is raised at run-time.

Adding the spring.main.allow-circular-references=true setting to the application.properties file resolves the error and allows the app to run successfully.

This code example is already set so that it will fail at run-time starting the application.

It will run successfully by either commenting and uncommenting the getDataSource methods shown here in the DemoApplication class.

@Bean
public DataSource getDataSource(RestTemplate restTemplate) {
// public DataSource getDataSource() {
    DataSourceBuilder dataSourceBuilder = DataSourceBuilder.create();
    dataSourceBuilder.driverClassName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
    dataSourceBuilder.url("<DB URL>");
    dataSourceBuilder.username("<DB USER NAME>");
    dataSourceBuilder.password("DB PASSWORD");
    return dataSourceBuilder.build();
}

Or by uncommenting the spring.main.allow-circular-references=true setting in the application.properties file.