abnormal
When the project starts, the console outputs abnormal content
2020-12-10 13:48:38.467 ERROR 13860 --- [ main] o.s.boot.SpringApplication : Application run failed
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'documentationPluginsBootstrapper' defined in URL [jar:file:/C:/Users/liuya/.m2/repository/io/springfox/springfox-spring-web/2.9.2/springfox-spring-web-2.9.2.jar!/springfox/documentation/spring/web/plugins/DocumentationPluginsBootstrapper.class]: Unsatisfied dependency expressed through constructor parameter 1; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'webMvcRequestHandlerProvider' defined in URL [jar:file:/C:/Users/liuya/.m2/repository/io/springfox/springfox-spring-web/2.9.2/springfox-spring-web-2.9.2.jar!/springfox/documentation/spring/web/plugins/WebMvcRequestHandlerProvider.class]: Unsatisfied dependency expressed through constructor parameter 1; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration$EnableWebMvcConfiguration': Unsatisfied dependency expressed through method 'setConfigurers' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springblade.core.tool.config.MessageConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'com.fasterxml.jackson.databind.ObjectMapper' available: more than one 'primary' bean found among candidates: [jacksonObjectMapper, objectMapper]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:769)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:218)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1338)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1185)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:554)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:514)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:321)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:319)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:863)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:744)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:391)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:312)
at org.springframework.boot.builder.SpringApplicationBuilder.run(SpringApplicationBuilder.java:140)
at org.springblade.core.launch.BladeApplication.run(BladeApplication.java:50)
at com.hxtx.stripmine.StripMinePlatformApplication.main(StripMinePlatformApplication.java:19)
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'webMvcRequestHandlerProvider' defined in URL [jar:file:/C:/Users/liuya/.m2/repository/io/springfox/springfox-spring-web/2.9.2/springfox-spring-web-2.9.2.jar!/springfox/documentation/spring/web/plugins/WebMvcRequestHandlerProvider.class]: Unsatisfied dependency expressed through constructor parameter 1; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration$EnableWebMvcConfiguration': Unsatisfied dependency expressed through method 'setConfigurers' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springblade.core.tool.config.MessageConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'com.fasterxml.jackson.databind.ObjectMapper' available: more than one 'primary' bean found among candidates: [jacksonObjectMapper, objectMapper]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:769)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:218)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1338)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1185)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:554)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:514)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:321)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:319)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.addCandidateEntry(DefaultListableBeanFactory.java:1489)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1453)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveMultipleBeans(DefaultListableBeanFactory.java:1344)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1231)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1193)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)
... 19 common frames omitted
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration$EnableWebMvcConfiguration': Unsatisfied dependency expressed through method 'setConfigurers' parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springblade.core.tool.config.MessageConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'com.fasterxml.jackson.databind.ObjectMapper' available: more than one 'primary' bean found among candidates: [jacksonObjectMapper, objectMapper]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:678)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:376)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1402)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:591)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:514)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:321)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:319)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:392)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1318)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1158)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:554)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:514)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:321)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:319)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.addCandidateEntry(DefaultListableBeanFactory.java:1489)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1453)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveMultipleBeans(DefaultListableBeanFactory.java:1344)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1231)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1193)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)
... 36 common frames omitted
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springblade.core.tool.config.MessageConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'com.fasterxml.jackson.databind.ObjectMapper' available: more than one 'primary' bean found among candidates: [jacksonObjectMapper, objectMapper]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:769)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:218)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1338)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1185)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:554)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:514)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:321)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:319)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.addCandidateEntry(DefaultListableBeanFactory.java:1489)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1453)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveMultipleBeans(DefaultListableBeanFactory.java:1344)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1231)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1193)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:670)
... 62 common frames omitted
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'com.fasterxml.jackson.databind.ObjectMapper' available: more than one 'primary' bean found among candidates: [jacksonObjectMapper, objectMapper]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.determinePrimaryCandidate(DefaultListableBeanFactory.java:1555)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.determineAutowireCandidate(DefaultListableBeanFactory.java:1515)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1248)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1193)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)
... 78 common frames omitted
According to the console, the reason for the thrown exception is that there is no qualified bean of type "com.fasterxml.jackson.databind". When loading the ObjectMapper class, multiple ObjectMappers with @Primary were found in the candidate objects. ObjectMapper is a bean of the Jackson-databind class library.
problem code
/**
* 序列化，处理前端long 18位精确度失去问题(前端用String类型的雪花ID保持精度，后端及数据库继续使用Long(BigINT)类型不影响数据库查询执行效率。)
* @description
* @author tarzan Liu
* @version 1.0.0
* @date 2020/12/2
*/
@Configuration
public class JacksonConfig {
@Bean
@Primary
@ConditionalOnMissingBean(ObjectMapper.class)
public ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder)
{
ObjectMapper objectMapper = builder.createXmlMapper(false).build();
// 全局配置序列化返回 JSON 处理
SimpleModule simpleModule = new SimpleModule();
//JSON Long ==> String
simpleModule.addSerializer(Long.class, ToStringSerializer.instance);
objectMapper.registerModule(simpleModule);
return objectMapper;
}
}Solution
Because the third-party jar is referenced in the project, @Primary may also be used for ObjectMapper in the third-party jar, causing conflicts. Remove @Primary in the code to solve the exception
Summarize
This exception usually occurs in Spring applications, indicating that multiple eligible primary (Primary) candidates were found during the autowiring process. In this case, Spring cannot determine which Bean to inject as the main dependency, resulting in an exception being thrown.
The reason for this exception may be that there are multiple beans of the same type in the application context, and it is not clearly specified which bean should be the main bean. There are several ways to solve this problem:
- Explicitly specify the main bean: Use annotations on the definition of one of the beans
@Primaryto identify it as the main bean. For example:
@Bean
@Primary
public ObjectMapper jacksonObjectMapper() {
// 配置并返回ObjectMapper实例
}
or
@Bean
@Primary
public ObjectMapper objectMapper() {
// 配置并返回ObjectMapper实例
}
@PrimaryThe ambiguity during autowiring is resolved by using annotations to mark one of the beans as the main bean.
- Use Qualifier: If you don't want to specify a main bean, you can explicitly specify the bean to be injected by using the qualifier annotation. Use annotations where injection is required
@Qualifier, and specify the name of the corresponding Bean. For example:
@Autowired
@Qualifier("jacksonObjectMapper")
private ObjectMapper objectMapper;
or
@Autowired
@Qualifier("objectMapper")
private ObjectMapper objectMapper;
The ambiguity is resolved by using @Qualifierannotations to tell Spring which specific Bean to inject.
The above are two commonly used solutions. Choose the appropriate method to eliminate the exception according to your specific needs.
Supplementary knowledge
@PrimaryIt is an annotation in the Spring framework, which is used to identify that among multiple candidate beans, the annotated bean should be preferred as the first choice for automatic assembly.
When there are multiple candidate beans of the same type, if they are not marked with @Primaryannotations, Spring cannot determine which bean to choose for automatic assembly, and an exception will be thrown. The bean that uses @Primarythe annotation will be considered as the primary (Primary) bean by default and has a higher priority.
Here are some key points and @Primaryconsiderations for using annotations:
- Use annotations on a bean definition or configuration method
@Primaryto indicate that the bean is the main bean. @PrimaryAnnotations can only be used on one bean definition, and multiple beans cannot be marked at the same time.- The main bean has a higher priority than other non-main beans and will be selected first when autowiring.
- If you need to specify a specific bean for autowiring, you can use
@Qualifierannotations@Primarytogether with annotations. @PrimaryAnnotations are often used to disambiguate autowiring to ensure that the primary bean is correctly selected in the case of multiple candidate beans.
@PrimaryHere is an example showing how to use annotations in Spring :
@Component
@Primary
public class JacksonObjectMapper implements ObjectMapper {
// 实现自定义的ObjectMapper逻辑
}
In the above example, JacksonObjectMapperit is marked as the primary bean (Primary Bean), and ObjectMapperSpring will give priority to the annotated one when an automatic assembly type of dependency @Primaryis required JacksonObjectMapper.
In summary, @Primaryannotations are used to resolve the ambiguity of multiple candidate beans in auto-assembly, by marking one of the beans as the main bean to ensure that the main bean is correctly selected during auto-assembly.