09:28:24.323 [main] ERROR org.springframework.boot.SpringApplication - Application startup failed java.lang.NullPointerException: null at org.springframework.core.BridgeMethodResolver.findBridgedMethod(BridgeMethodResolver.java:64) at org.springframework.beans.GenericTypeAwarePropertyDescriptor.(GenericTypeAwarePropertyDescriptor.java:70) at org.springframework.beans.CachedIntrospectionResults.buildGenericTypeAwarePropertyDescriptor(CachedIntrospectionResults.java:366) at org.springframework.beans.CachedIntrospectionResults.(CachedIntrospectionResults.java:302) at org.springframework.beans.CachedIntrospectionResults.forClass(CachedIntrospectionResults.java:189) at org.springframework.beans.BeanUtils.getPropertyDescriptors(BeanUtils.java:354) at org.springframework.boot.bind.PropertiesConfigurationFactory.getNames(PropertiesConfigurationFactory.java:303) at org.springframework.boot.bind.PropertiesConfigurationFactory.doBindPropertiesToTarget(PropertiesConfigurationFactory.java:284) at org.springframework.boot.bind.PropertiesConfigurationFactory.bindPropertiesToTarget(PropertiesConfigurationFactory.java:250) at org.springframework.boot.context.config.ConfigFileApplicationListener.bindToSpringApplication(ConfigFileApplicationListener.java:241) at org.springframework.boot.context.config.ConfigFileApplicationListener.postProcessEnvironment(ConfigFileApplicationListener.java:197) at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEnvironmentPreparedEvent(ConfigFileApplicationListener.java:182) at org.springframework.boot.context.config.ConfigFileApplicationListener.onApplicationEvent(ConfigFileApplicationListener.java:168) at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:122) at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:74) at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54) at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:325) at org.springframework.boot.SpringApplication.run(SpringApplication.java:296) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1118) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1107) at com.aming.CCApplication.main(CCApplication.java:14) Disconnected from the target VM, address: ‘127.0.0.1:55840’, transport: ‘socket’
经过反复排查对比，最终发现问题出在pom依赖问题上。把spring-core这个依赖删掉就可以了
<dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>5.1.8.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <version>1.5.12.RELEASE</version> </dependency>其中spring-boot-starter-web是内置tomcat，启动springboot，web项目的核心所在，点开发现里面的spring-boot-starter依赖中，包含了spring-core，所以目前只能探究到会不会是两个不同版本的spring-core在一起发生了冲突。下一篇文章继续深入探讨。
