dubbo服务调用报错，哪位大神知道这是什么错误

Question

Caused by: com.alibaba.com.caucho.hessian.io.HessianProtocolException: 'org.springframework.beans.factory.NoUniqueBeanDefinitionException' could not be instantiated
at com.alibaba.com.caucho.hessian.io.JavaDeserializer.instantiate(JavaDeserializer.java:275) ~[dubbo-2.8.4.jar:2.8.4]
at com.alibaba.com.caucho.hessian.io.JavaDeserializer.readObject(JavaDeserializer.java:155) ~[dubbo-2.8.4.jar:2.8.4]
at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObjectInstance(Hessian2Input.java:2067) ~[dubbo-2.8.4.jar:2.8.4]
at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:1592) ~[dubbo-2.8.4.jar:2.8.4]
at com.alibaba.com.caucho.hessian.io.Hessian2Input.readObject(Hessian2Input.java:1576) ~[dubbo-2.8.4.jar:2.8.4]
at com.alibaba.com.caucho.hessian.io.JavaDeserializer$ObjectFieldDeserializer.deserialize(JavaDeserializer.java:396) ~[dubbo-2.8.4.jar:2.8.4]
... 27 common frames omitted
Caused by: java.lang.reflect.InvocationTargetException: null
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_191]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_191]
at com.alibaba.com.caucho.hessian.io.JavaDeserializer.instantiate(JavaDeserializer.java:271) ~[dubbo-2.8.4.jar:2.8.4]
... 32 common frames omitted
Caused by: java.lang.NullPointerException: null
at java.util.Objects.requireNonNull(Objects.java:203) ~[na:1.8.0_191]
at java.util.Arrays$ArrayList.(Arrays.java:3813) ~[na:1.8.0_191]
at java.util.Arrays.asList(Arrays.java:3800) ~[na:1.8.0_191]
at org.springframework.beans.factory.NoUniqueBeanDefinitionException.(NoUniqueBeanDefinitionException.java:65) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
... 37 common frames omitted

Answer 1

接口有两个以上实现类吗？这个错大概就是Spring不晓得应该注册哪一个bean，你的实现类不是唯一的，可以用@Primary注解告诉Spring优先选择哪个实现类作为实现。或者使用@Qualifier注解给bean设置唯一的名字，注入的时候给定bean的名字就好了， 你后面那种方法告诉了Sping用BaseDaoInter这个实现类(大概), Spring就知道怎么做了。