Spring 循环引用解决方案

蔚落 2022-05-08 01:04 239阅读 0赞

> # **Spring 循环引用解决方案** #

## 一、问题呈现： ##

![70][]

上述memberMerchantService 和 memberService 互相引用或者深层注入引用 导致项目启动不了

**【详细问题描述】：**

Bean with name ‘xxxService’ has been injected into other beans [xxxService] in its raw version as part of a circular reference, but has eventually been wrapped. This means that said other beans do not use the final version of the bean. This is often the result of over-eager type matching – consider using ‘getBeanNamesOfType’ with the ‘allowEagerInit’ flag turned off, for example.

** 【简单分析 导致原因】：**

**代码设计得比较耦合，将相关逻辑拆分后得到解决。不管我如何拆解都如影随形，已经不是简单的A->B，B->A的循环引用了，而是深层次的逻辑耦合，要解耦比较困难，说明在设计阶段有提高的余地。诡异的是，在融入另一个项目前是不会抛这个错误的，可见问题可能出在和新项目融合后的配置文件上。**

**大神Juergen Hoeller说：**

This is probably a consequence of the bean initialization order having changed, in combination with auto-proxying and maybe a pointcut that is too broad.

## 二、解决方案：  ##

** （一）、解耦合，从本质出发，分析代码我们知道，memberMerchantService 与memberService互相深层注入引用，导致循环引用，去掉一方或者替代掉即可**

**（二）、解决方案，有一个参数setAllowRawInjectionDespiteWrapping，默认是false，将其设成true即可。代码如下：[【参考文献】][Link 1]**

public class MyWebApplicationContext extends XmlWebApplicationContext {
        @Override
        protected DefaultListableBeanFactory createBeanFactory() {
            DefaultListableBeanFactory beanFactory = super.createBeanFactory();
            beanFactory.setAllowRawInjectionDespiteWrapping(true);
            return beanFactory;
        }
    }

**然后在web.xml配置启用此context ：**

<context-param>        
        <param-name>contextClass</param-name>        
        <param-value>xxx.MyWebApplicationContext</param-value>    
    </context-param>

[70]: /images/20220508/cf82fb29bc734805813a40e992df2947.png
[Link 1]: https://blog.csdn.net/zgmzyr/article/details/7255791