How is the problem of cyclic component dependencies eliminated when using Spring?

The cyclic dependency problem in Spring occurs when two or more components depend on each other directly, leading to an error during bean creation.

Ways to resolve:

• Using the @Lazy annotation — allows delaying the creation of one of the dependent components until it is actually used, breaking the cycle.

• Injecting dependencies via setters or methods, rather than through the constructor — constructor dependencies create a tight cycle, while setters allow Spring to first create beans and then set dependencies.

• Refactoring architecture — extracting common dependencies into a separate bean to avoid direct cyclicity.

Example with @Lazy:

@Component
public class A {
    private final B b;

    public A(@Lazy B b) {
        this.b = b;
    }
}

@Component
public class B {
    private final A a;

    public B(A a) {
        this.a = a;
    }
}

Here, @Lazy on B in class A allows Spring to first create B, and then inject it into A, breaking the cycle.