Injection of @DubboReference dependencies is failed； java.lang.NullPointerException空指针踩坑记

dubbo项目

@DubboReference注解引用的dubbo接口

项目启动报
Injection of @DubboReference dependencies is failed; nested exception is java.lang.NullPointerException

网上的说明 都是包冲突什么的，解决了很多的包冲突后，问题依然存在

后改为 @DubboReference(check=false) 问题依旧

因为项目内有接口是自提供的，排查injvm方式引用，加入 @DubboReference(check = false, injvm = false)排查spring内部依赖问题

问题终于初见端倪 报了具体的空指针错误位置

java.lang.NullPointerException: null
    at org.apache.dubbo.common.extension.support.ActivateComparator.parseActivate(ActivateComparator.java:111)
    at org.apache.dubbo.common.extension.support.ActivateComparator.compare(ActivateComparator.java:52)
    at java.base/java.util.TimSort.countRunAndMakeAscending(TimSort.java:355)
    at java.base/java.util.TimSort.sort(TimSort.java:220)
    at java.base/java.util.Arrays.sort(Arrays.java:1515)
    at java.base/java.util.ArrayList.sort(ArrayList.java:1750)
    at org.apache.dubbo.common.extension.ExtensionLoader.getActivateExtension(ExtensionLoader.java:287)
    at org.apache.dubbo.common.extension.ExtensionLoader.getActivateExtension(ExtensionLoader.java:248)

后断点调试，找到空指针所在参数：
org.apache.dubbo.common.extension.support.ActivateComparator

在 info.before = activate.before();断点  找到 activate为null的那个clazz ，发现自定义dubbo过滤器未使用@Activate注解导致此处空指针
  private ActivateComparator.ActivateInfo parseActivate(Class clazz) {
        ActivateComparator.ActivateInfo info = new ActivateComparator.ActivateInfo();
        if (clazz.isAnnotationPresent(Activate.class)) {
            Activate activate = (Activate)clazz.getAnnotation(Activate.class);
            info.before = activate.before();
            info.after = activate.after();
            info.order = activate.order();
        } else {
            com.alibaba.dubbo.common.extension.Activate activate = (com.alibaba.dubbo.common.extension.Activate)clazz.getAnnotation(com.alibaba.dubbo.common.extension.Activate.class);
            info.before = activate.before();
            info.after = activate.after();
            info.order = activate.order();
        }

        return info;
    }