spring 循环依赖 form stackoverflow

The Spring container is able to resolve Setter-based circular dependencies but gives a runtime exception BeanCurrentlyInCreationException in case of Constructor-based circular dependencies. In case of Setter-based circular dependency, the IOC container handles it differently from a typical scenario wherein it would fully configure the collaborating bean before injecting it. For eg., if Bean A has a dependency on Bean B and Bean B on Bean C, the container fully initializes C before injecting it to B and once B is fully initialized it is injected to A. But in case of circular dependency, one of the beans is injected to the other before it is fully initialized.

There are many ways to deal with circular dependencies in Spring. The first thing to consider is to redesign your beans so there is no need for circular dependencies: they are usually a symptom of a design that can be improved.

But if you absolutely need to have circular dependencies in your project, you can follow some of the workarounds suggested here.

The preferred method is using setter injections. But there are other alternatives, generally based on stopping Spring from managing the initialization and injection of the beans, and doing that yourself using one strategy or another.

reference :参考资料