问题

I'm having a problem with some Spring bean definitions. I have a couple of context xml files that are being loaded by my main() method, and both of them contain almost exclusively a tag. When my main method starts up, I get this error from Spring:

Caused by: org.springframework.context.annotation.ConflictingBeanDefinitionException: Annotation-specified bean name 'converterDAO' for bean class [my.package.InMemoryConverterDaoImpl] conflicts with existing, non-compatible bean definition of same name and class [my.other.package.StaticConverterDAOImpl]

Both DAO classes are annotated this way:

@Repository("converterDAO")
public class StaticConverterDAOImpl implements ConverterDAO {
...
}

The in-memory dao also has the @Repository("converterDAO") annotation. The dao is referenced in other classes like this:

...
private @Autowired @Qualifier("converterDAO") ConverterDAO converterDAO;
...

I want one DAO to override the definition of the other one, which as I always understood it was one of the principal reasons to use a DI framework in the first place. I've been doing this with xml definitions for years and never had any problems. But not so with component scans and annotated bean definitions? And what does Spring mean when it says they are not "compatible"? They implement the same interface, and they are autowired into fields that are of that interface type. Why the heck are they not compatible?

Can someone provide me with a way for one annotated, component-scanned bean to override another?

-Mike

回答1:

In an XML file, there is a sequence of declarations, and you may override a previous definition with a newer one. When you use annotations, there is no notion of before or after. All the beans are at the same level. You defined two beans with the same name, and Spring doesn't know which one it should choose.

Give them a different name (staticConverterDAO, inMemoryConverterDAO for example), create an alias in the Spring XML file (theConverterDAO for example), and use this alias when injecting the converter:

@Autowired @Qualifier("theConverterDAO")

回答2:

I had a similar problem, with two jar libraries (app1 and app2) in one project. The bean "BeanName" is defined in app1 and is extended in app2 and the bean redefined with the same name.

In app1:

package com.foo.app1.pkg1;

@Component("BeanName")
public class Class1 { ... }

In app2:

package com.foo.app2.pkg2;

@Component("BeanName")
public class Class2 extends Class1 { ... }

This causes the ConflictingBeanDefinitionException exception in the loading of the applicationContext due to the same component bean name.

To solve this problem, in the Spring configuration file applicationContext.xml:

<context:component-scan base-package="com.foo.app2.pkg2"/>
<context:component-scan base-package="com.foo.app1.pkg1">
    <context:exclude-filter type="assignable" expression="com.foo.app1.pkg1.Class1"/>
</context:component-scan>

So the Class1 is excluded to be automatically component-scanned and assigned to a bean, avoiding the name conflict.

回答3:

I had a similar issue with Spring 4.x using @RestController. Two different packages had a class with the same name...

package com.x.catalog

@RestController
public class TextureController {
...

package com.x.cms
@RestController
public class TextureController {
...

The fix was easy...

package com.x.catalog

@RestController("CatalogTextureController")
public class TextureController {
...

package com.x.cms
@RestController("CMSTextureController")
public class TextureController {
...

The problem seems to be that the annotation gets autowired and takes the class name by default. Giving it an explicit name in the @RestController annotation allows you to keep the class names.

回答4:

I had a similar problem, and it was because one of my beans had been moved to another directory recently. I needed to do a "build clean" by deleting the build/classes/java directory and the problem went away. (The error message had the two different file paths conflicting with each other, although I knew one should not actually exist anymore.)

回答5:

Sometimes the problem occurs if you have moved your classes around and it refers to old classes, even if they don't exist.

In this case, just do this :

mvn eclipse:clean

mvn eclipse:eclipse

This worked well for me.

回答6:

Scenario:

I am working on a multi-module Gradle project.

Modules are:

- core, 
- service,
- geo,
- report,
- util and
- some other modules.

So primarily we have prepared a Component[locationRecommendHttpClientBuilder] in geo module.

Java Code:

import org.springframework.stereotype.Component

@Component("locationRecommendHttpClientBuilder")
class LocationRecommendHttpClientBuilder extends PanaromaHttpClientBuilder {
    @Override
    PanaromaHttpClient buildFromConfiguration() {
        this.setURL(PanaromaConf.getInstance().getString("locationrecommend.url"))
        this.setMethod(PanaromaConf.getInstance().getString("locationrecommend.method"))
        this.setProxyHost(PanaromaConf.getInstance().getString("locationrecommend.proxy.host"))
        this.setProxyPort(PanaromaConf.getInstance().getInt("locationrecommend.proxy.port", 0))
        return super.build()
    }
}

application-context.xml

<bean id="locationRecommendHttpClient"
      class="au.co.google.panaroma.platform.logic.impl.PanaromaHttpClient"
      scope="singleton" factory-bean="locationRecommendHttpClientBuilder"
      factory-method="buildFromConfiguration" />

Then it is decided to add this component in core module.

One engineer has previous code for geo module and then he has taken the latest module of core but he forgot to take the latest geo module.

So the component[locationRecommendHttpClientBuilder] is double times in his project and he was getting the following error.

Caused by: org.springframework.context.annotation.ConflictingBeanDefinitionException: Annotation-specified bean name 'LocationRecommendHttpClientBuilder' for bean class [au.co.google.app.locationrecommendation.builder.LocationRecommendHttpClientBuilder] conflicts with existing, non-compatible bean definition of same name and class [au.co.google.panaroma.platform.logic.impl.locationRecommendHttpClientBuilder]

Solution Procedure:

After removal the component from geo module, component[locationRecommendHttpClientBuilder] is only available in core module. So there is no conflicting situation. Issue is solved by this way.

回答7:

I also had a similar problem. I built the project again and the issue was resolved.

The reason is, there are already defined sequences for the Annotation-specified bean names, in a file. When we do a change on that bean name and try to run the application Spring cannot identify which one to pick. That is why it shows this error.

In my case, I removed the previous bean class from the project and added the same bean name to a new bean class. So Spring has the previous definition for the removed bean class in a file and that conflicts with the newly added class while compiling. So if you do a 'build clean', previous definitions for bean classes will be removed and compilation will success.

回答8:

I faced this issue when I imported a two project in the workspace. It created a different jar somehow so we can delete the jars and the class files and build the project again to get the dependencies right.

来源：https://stackoverflow.com/questions/13801359/annotation-specified-bean-name-conflicts-with-existing-non-compatible-bean-def

标签

Spring

repository

Annotation-specified bean name conflicts with existing, non-compatible bean def

问题