@Bean inside class with @Configuration and without it

Question

There is a @Bean annotation in Spring 3.0. It allows to define a Spring bean directly in a Java code. While browsing Spring reference I found two different ways

Answer 1

The difference is that with @Configuration you can call one @Bean method from another and get a fully initialized instance, as follows:

public class Foo {
    @Value("Hello, world!")
    public String value;
}

@Configuration
public class Config {
    @Bean
    public Foo createFoo() {
        Foo foo = new Foo();
        System.out.println(foo.value); // Prints null - foo not initialized yet
        return foo;
    }

    @Bean
    public Bar createBar() {
        Foo foo = createFoo();
        System.out.println(foo.value); // Prints Hello, world! - foo have been initialized by the interceptor
        return new Bar(foo);
    }
}