Grails supports setting of bean properties via configuration. This is often useful when used in combination with externalized configuration.

Essentially you define a beans block with the names of beans and their values:

beans {
    bookService {
        webServiceURL = "http://www.amazon.com"
    }
}

The general format is:

[bean name].[property name] = [value]

The same configuration in a Java properties file would be:

beans.bookService.webServiceURL=http://www.amazon.com