Spring源码解析
doPost
javax.validation.constraints isValidinvokeHandlerMethod
processRequest
WebServelet启动过程:
createWebServer
getWebServerFactory初始化tomcat容器
@Override
public WebServer getWebServer(ServletContextInitializer... initializers) {
if (this.disableMBeanRegistry) {
Registry.disableRegistry();
}
Tomcat tomcat = new Tomcat();
File baseDir = (this.baseDirectory != null) ? this.baseDirectory : createTempDir("tomcat");
tomcat.setBaseDir(baseDir.getAbsolutePath());
Connector connector = new Connector(this.protocol);
connector.setThrowOnFailure(true);
tomcat.getService().addConnector(connector);
customizeConnector(connector);
tomcat.setConnector(connector);
tomcat.getHost().setAutoDeploy(false);
configureEngine(tomcat.getEngine());
for (Connector additionalConnector : this.additionalTomcatConnectors) {
tomcat.getService().addConnector(additionalConnector);
}
prepareContext(tomcat.getHost(), initializers);
return getTomcatWebServer(tomcat);
}public class Tomcat {
...
}
解析带注解的方法参数: 注解PathVariable的解析
@GetMapping(path = "/{id}/",produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity getObj(@PathVariable long id) {
City obj = entityManager.find(City.class, id);
return this.responseEntity.success(obj);
}通过PathVariableMethodArgumentResolver.supportsParameter解析参数id的注解PathVariable @Override
public boolean supportsParameter(MethodParameter parameter) {
if (!parameter.hasParameterAnnotation(PathVariable.class)) {
return false;
}
if (Map.class.isAssignableFrom(parameter.nestedIfOptional().getNestedParameterType())) {
PathVariable pathVariable = parameter.getParameterAnnotation(PathVariable.class);
return (pathVariable != null && StringUtils.hasText(pathVariable.value()));
}
return true;
}
以此类推,通过这个类的接口联想到其他的参数的XXXMethodArgumentResolver
解析出来的是id,提供给HttpServerletRequest.getHeader获取
HttpServlet.service根据method处理不同请求:
Servlet on Spring Boot
组件: 扫描 \ 注册 HttpServlet
filter: 扫描 \ 注册 Filter
listener: 扫描 \ 注册 XXXXListener
请求处理流程：
HttpServlet.doService-->FrameworkServlet.processRequest--->DispatcherServlet.doService--->
DispatcherServlet.doDispatch:
mv = ha.handle(processedRequest, response, mappedHandler.getHandler());--->CityController.getObj
PropertyMapper
@Override
public void customize(ConfigurableServletWebServerFactory factory) {
PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();
map.from(this.serverProperties::getPort).to(factory::setPort);
map.from(this.serverProperties::getAddress).to(factory::setAddress);
map.from(this.serverProperties.getServlet()::getContextPath).to(factory::setContextPath);
map.from(this.serverProperties.getServlet()::getApplicationDisplayName).to(factory::setDisplayName);
map.from(this.serverProperties.getServlet()::getSession).to(factory::setSession);
map.from(this.serverProperties::getSsl).to(factory::setSsl);
map.from(this.serverProperties.getServlet()::getJsp).to(factory::setJsp);
map.from(this.serverProperties::getCompression).to(factory::setCompression);
map.from(this.serverProperties::getHttp2).to(factory::setHttp2);
map.from(this.serverProperties::getServerHeader).to(factory::setServerHeader);
map.from(this.serverProperties.getServlet()::getContextParameters).to(factory::setInitParameters);
}
一次报错打印的stacktrace：
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
[2020-02-13 21:48:43.576] [ERROR] org.springframework.boot.SpringApplication:826 Application run failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class: ik.starriver.msgcenter.entity.Store.customers[ik.starriver.msgcenter.entity.Customer]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1796)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:595)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1108)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:868)
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:747)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:315)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215)
at ik.starriver.msgcenter.MsgCenterApplication.main(MsgCenterApplication.java:43)
Caused by: org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class: ik.starriver.msgcenter.entity.Store.customers[ik.starriver.msgcenter.entity.Customer]
at org.hibernate.cfg.annotations.CollectionBinder.bindManyToManySecondPass(CollectionBinder.java:1332)
at org.hibernate.cfg.annotations.CollectionBinder.bindStarToManySecondPass(CollectionBinder.java:870)
at org.hibernate.cfg.annotations.CollectionBinder$1.secondPass(CollectionBinder.java:795)
at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:53)
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1684)
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1652)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:286)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:1202)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1233)
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:391)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:378)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1855)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1792)
... 16 common frames omitted
Disconnected from the target VM, address: '127.0.0.1:54832', transport: 'socket'
Process finished with exit code 1