spring-framework
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Cyclic dependency with constructor injection
Background
Spring is discouraging use of filed injection, and in favor or constructor injection.
However, when the beans need to cross reference to each other. For example:
class BeanA{
@Autowired
public BeanA(BeanB beanB) {
this.beanB= beanB;
}
}
class BeanB{
@Autowired
public BeanB(BeanA beanA) {
this.beanA= beanA;
}
this will instead throw out exception
APPLICATION FAILED TO START
***************************
Description:
The dependencies of some of the beans in the application context form a cycle:
┌─────┐
| beanA defined in URL [jar:file:/...class]
↑ ↓
| beanB defined in URL [jar:file:/....class]
↑ ↓
| xx (field xx)
Changes
Instead of just saying "Field injection is not recommended", can we make it clear, by adding
Field injection is not recommended **however, please don't constructor injection with circular reference** ?
?
Related Issues
- #25443
- #27534
- #30333
