Spring异常分析

异常报错

2019-01-14 10:40:18.427 ERROR 11776 --- [ost-startStop-1] o.s.b.w.e.t.TomcatStarter                : Error starting Tomcat context.

Exception: org.springframework.beans.factory.BeanCreationException. Message: Error creating bean with name 'servletEndpointRegistrar' defined in class path resource [org/springframework/boot/actuate/autoconfigure/endpoint/web/ServletEndpointManagementContextConfiguration$WebMvcServletEndpointManagementContextConfiguration.class]:

Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException:

Failed to instantiate [org.springframework.boot.actuate.endpoint.web.ServletEndpointRegistrar]:

Factory method 'servletEndpointRegistrar' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException:

Error creating bean with name 'healthEndpoint' defined in class path resource [org/springframework/boot/actuate/autoconfigure/health/HealthEndpointConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.actuate.health.HealthEndpoint]: Factory method 'healthEndpoint' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException:

Error creating bean with name 'org.springframework.boot.actuate.autoconfigure.jdbc.DataSourceHealthIndicatorAutoConfiguration':
Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException:

Failed to instantiate [org.springframework.boot.actuate.autoconfigure.jdbc.DataSourceHealthIndicatorAutoConfiguration$$EnhancerBySpringCGLIB$$caa88ea6]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException:

Error creating bean with name 'dataSource': Post-processing of FactoryBean's singleton object failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class]:

Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: Failed to determine a suitable driver class

关键在最后一句Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: Failed to determine a suitable driver class

我这里是有配置mysql驱动的。所以定位应该是配置问题。

根据提示，可以看出是从DataSourceProperties这里抛出来的异常。读取spring.datasource开头的配置项。如果spring.datasource.driverClassName为空，会抛出异常，提示Failed to determine a suitable driver class

我的配置文件里是有配置的，该配置在读取时会将driver-class-name转换为驼峰式写法driverClassName。所以问题应该是Springboot没有加载application.properties的问题，可以来验证一下。

启动后，异常信息变成

Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.autoconfigure.jdbc.DataSourceProperties$DataSourceBeanCreationException: Failed to determine suitable jdbc url

spring.datasource.driver-class-name=com.mysql.jdbc.Driver

@ConfigurationProperties(prefix = "spring.datasource")
public class DataSourceProperties implements BeanClassLoaderAware, InitializingBean {

public String determineDriverClassName() {
if (StringUtils.hasText(this.driverClassName)) {
Assert.state(driverClassIsLoadable(),
() -> "Cannot load driver class: " + this.driverClassName);
return this.driverClassName;
}
String driverClassName = null;
if (StringUtils.hasText(this.url)) {
driverClassName = DatabaseDriver.fromJdbcUrl(this.url).getDriverClassName();
}
if (!StringUtils.hasText(driverClassName)) {
driverClassName = this.embeddedDatabaseConnection.getDriverClassName();
}
if (!StringUtils.hasText(driverClassName)) {
throw new DataSourceBeanCreationException(
"Failed to determine a suitable driver class", this,
this.embeddedDatabaseConnection);
}
return driverClassName;
}

}

测试加载的配置文件

public class KzfApiAlipayApplication {

public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(KzfApiAlipayApplication.class, args);
System.out.println(context.getEnvironment().getProperty("spring.datasource.driver-class-name"));
}

}

public class ServletEndpointManagementContextConfiguration {

@Configuration
@ConditionalOnClass(DispatcherServlet.class)
public static class WebMvcServletEndpointManagementContextConfiguration {

private final ApplicationContext context;

public WebMvcServletEndpointManagementContextConfiguration(
ApplicationContext context) {
this.context = context;
}

@Bean
public ServletEndpointRegistrar servletEndpointRegistrar(
WebEndpointProperties properties,
ServletEndpointsSupplier servletEndpointsSupplier) {
DispatcherServletPath dispatcherServletPath = this.context
.getBean(DispatcherServletPath.class);
return new ServletEndpointRegistrar(
dispatcherServletPath.getRelativePath(properties.getBasePath()),
servletEndpointsSupplier.getEndpoints());
}

}

}

SpringBoot启动过程

@SpringBootApplication
public class CrawlerDiscreditApplication {

public static void main(String[] args) {

SpringApplication.run(CrawlerDiscreditApplication.class, args);

}

}

SpringApplication类

public class SpringApplication {

private ResourceLoader resourceLoader;

public SpringApplication(Class<?>... primarySources) {
this(null, primarySources);
}

public SpringApplication(ResourceLoader resourceLoader, Class<?>... primarySources) {
this.resourceLoader = resourceLoader;
Assert.notNull(primarySources, "PrimarySources must not be null");
this.primarySources = new LinkedHashSet<>(Arrays.asList(primarySources));
this.webApplicationType = deduceWebApplicationType();
setInitializers((Collection) getSpringFactoriesInstances(
ApplicationContextInitializer.class));
setListeners((Collection) getSpringFactoriesInstances(ApplicationListener.class));
this.mainApplicationClass = deduceMainApplicationClass();
}

}