這篇“springboot中如何利用Tomcat容器實現(xiàn)自啟動”文章的知識點大部分人都不太理解，所以小編給大家總結(jié)了以下內(nèi)容，內(nèi)容詳細(xì)，步驟清晰，具有一定的借鑒價值，希望大家閱讀完這篇文章能有所收獲，下面我們一起來看看這篇“springboot中如何利用Tomcat容器實現(xiàn)自啟動”文章吧。
創(chuàng)新互聯(lián)建站是一家專業(yè)的成都網(wǎng)站建設(shè)公司，我們專注做網(wǎng)站、成都做網(wǎng)站、網(wǎng)絡(luò)營銷、企業(yè)網(wǎng)站建設(shè)，賣鏈接，1元廣告為企業(yè)客戶提供一站式建站解決方案，能帶給客戶新的互聯(lián)網(wǎng)理念。從網(wǎng)站結(jié)構(gòu)的規(guī)劃UI設(shè)計到用戶體驗提高，創(chuàng)新互聯(lián)力求做到盡善盡美。
1、通過實現(xiàn)ImportSerlector接口，實現(xiàn)Bean加載：
重慶分公司
重慶分公司
public class TestServiceImpl {
public void testImpl() {
System.out.println("我是通過importSelector導(dǎo)入進來的service");
}
}
public class TestService implements ImportSelector {
@Override
public String[] selectImports(AnnotationMetadata annotationMetadata) {
return new String[]{"com.ycdhz.service.TestServiceImpl"};
}
}
@Configuration
@Import(value = {TestService.class})
public class TestConfig {
}
public class TestController {
@Autowired
private TestServiceImpl testServiceImpl;
@RequestMapping("testImpl")
public String testTuling() {
testServiceImpl.testImpl();
return "Ok";
}
}2、 通過實現(xiàn)ImportSerlector接口，實現(xiàn)Bean加載：
public class TestService {
public TestService() {
System.out.println("我是通過ImportBeanDefinitionRegistrar導(dǎo)入進來的組件");
}
}
public class TestImportBeanDefinitionRegistrar implements ImportBeanDefinitionRegistrar {
@Override
public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
//定義一個BeanDefinition
RootBeanDefinition beanDefinition = new RootBeanDefinition(TestService.class);
//把自定義的bean定義導(dǎo)入到容器中
registry.registerBeanDefinition("testService",beanDefinition);
}
}
@Configuration
@Import(TestImportBeanDefinitionRegistrar.class)
public class TestConfig {
}我們從spring-boot-autoconfigure-2.0.6.RELEASE.jar下搜索到Tomcat的相關(guān)配置，發(fā)現(xiàn)有兩個自動裝配類，分別包含了三個定制器（面向?qū)ο蟮膯我宦氊?zé)原則），還有一個工廠類。
2.1、TomcatWebServerFactoryCustomizer：定制Servlet和Reactive服務(wù)器通用的Tomcat特定功能。
public class TomcatWebServerFactoryCustomizer implements WebServerFactoryCustomizer, Ordered { @Override public void customize(ConfigurableTomcatWebServerFactory factory) { ServerProperties properties = this.serverProperties; ServerProperties.Tomcat tomcatProperties = properties.getTomcat(); PropertyMapper propertyMapper = PropertyMapper.get(); propertyMapper.from(tomcatProperties::getBasedir).whenNonNull() .to(factory::setBaseDirectory); propertyMapper.from(tomcatProperties::getBackgroundProcessorDelay).whenNonNull() .as(Duration::getSeconds).as(Long::intValue) .to(factory::setBackgroundProcessorDelay); customizeRemoteIpValve(factory); propertyMapper.from(tomcatProperties::getMaxThreads).when(this::isPositive) .to((maxThreads) -> customizeMaxThreads(factory, tomcatProperties.getMaxThreads())); propertyMapper.from(tomcatProperties::getMinSpareThreads).when(this::isPositive) .to((minSpareThreads) -> customizeMinThreads(factory, minSpareThreads)); propertyMapper.from(() -> determineMaxHttpHeaderSize()).when(this::isPositive) .to((maxHttpHeaderSize) -> customizeMaxHttpHeaderSize(factory, maxHttpHeaderSize)); propertyMapper.from(tomcatProperties::getMaxHttpPostSize) .when((maxHttpPostSize) -> maxHttpPostSize != 0) .to((maxHttpPostSize) -> customizeMaxHttpPostSize(factory, maxHttpPostSize)); propertyMapper.from(tomcatProperties::getAccesslog) .when(ServerProperties.Tomcat.Accesslog::isEnabled) .to((enabled) -> customizeAccessLog(factory)); propertyMapper.from(tomcatProperties::getUriEncoding).whenNonNull() .to(factory::setUriEncoding); propertyMapper.from(properties::getConnectionTimeout).whenNonNull() .to((connectionTimeout) -> customizeConnectionTimeout(factory, connectionTimeout)); propertyMapper.from(tomcatProperties::getMaxConnections).when(this::isPositive) .to((maxConnections) -> customizeMaxConnections(factory, maxConnections)); propertyMapper.from(tomcatProperties::getAcceptCount).when(this::isPositive) .to((acceptCount) -> customizeAcceptCount(factory, acceptCount)); customizeStaticResources(factory); customizeErrorReportValve(properties.getError(), factory); } }
2.2、ServletWebServerFactoryCustomizer：WebServerFactoryCustomizer 將ServerProperties屬性應(yīng)用于Tomcat web服務(wù)器。
public class ServletWebServerFactoryCustomizer implements WebServerFactoryCustomizer, Ordered { private final ServerProperties serverProperties; public ServletWebServerFactoryCustomizer(ServerProperties serverProperties) { this.serverProperties = serverProperties; } @Override public int getOrder() { return 0; } @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); } }
2.3、ServletWebServerFactoryCustomizer ：WebServerFactoryCustomizer 將ServerProperties屬性應(yīng)用于Tomcat web服務(wù)器。
public class TomcatServletWebServerFactoryCustomizer implements WebServerFactoryCustomizer, Ordered { private final ServerProperties serverProperties; public TomcatServletWebServerFactoryCustomizer(ServerProperties serverProperties) { this.serverProperties = serverProperties; } @Override public void customize(TomcatServletWebServerFactory factory) { ServerProperties.Tomcat tomcatProperties = this.serverProperties.getTomcat(); if (!ObjectUtils.isEmpty(tomcatProperties.getAdditionalTldSkipPatterns())) { factory.getTldSkipPatterns() .addAll(tomcatProperties.getAdditionalTldSkipPatterns()); } if (tomcatProperties.getRedirectContextRoot() != null) { customizeRedirectContextRoot(factory, tomcatProperties.getRedirectContextRoot()); } if (tomcatProperties.getUseRelativeRedirects() != null) { customizeUseRelativeRedirects(factory, tomcatProperties.getUseRelativeRedirects()); } } }
通過AbstractApplicationContext#onReFresh()在IOC 容器中的帶動tomcat啟動，然后在接著執(zhí)行 ioc容器的其他步驟。
我們通過斷點可以觀察Tomcat加載的整個生命周期，以及三個定制器的加載過程。
@Override
public WebServer getWebServer(ServletContextInitializer... initializers) {
Tomcat tomcat = new Tomcat();
File baseDir = (this.baseDirectory != null) ? this.baseDirectory
: createTempDir("tomcat");
tomcat.setBaseDir(baseDir.getAbsolutePath());
Connector connector = new Connector(this.protocol);
tomcat.getService().addConnector(connector);
customizeConnector(connector);
tomcat.setConnector(connector);
//設(shè)置是否自動啟動
tomcat.getHost().setAutoDeploy(false);
//創(chuàng)建Tomcat引擎
configureEngine(tomcat.getEngine());
for (Connector additionalConnector : this.additionalTomcatConnectors) {
tomcat.getService().addConnector(additionalConnector);
}
//刷新上下文
prepareContext(tomcat.getHost(), initializers);
//準(zhǔn)備啟動
return getTomcatWebServer(tomcat);
}private void initialize() throws WebServerException {
TomcatWebServer.logger
.info("Tomcat initialized with port(s): " + getPortsDescription(false));
synchronized (this.monitor) {
try {
addInstanceIdToEngineName();
Context context = findContext();
context.addLifecycleListener((event) -> {
if (context.equals(event.getSource())
&& Lifecycle.START_EVENT.equals(event.getType())) {
// Remove service connectors so that protocol binding doesn't
// happen when the service is started.
removeServiceConnectors();
}
});
// Start the server to trigger initialization listeners
this.tomcat.start();
// We can re-throw failure exception directly in the main thread
rethrowDeferredStartupExceptions();
try {
ContextBindings.bindClassLoader(context, context.getNamingToken(),
getClass().getClassLoader());
}
catch (NamingException ex) {
// Naming is not enabled. Continue
}
// Unlike Jetty, all Tomcat threads are daemon threads. We create a
// blocking non-daemon to stop immediate shutdown
startDaemonAwaitThread();
}
catch (Exception ex) {
stopSilently();
throw new WebServerException("Unable to start embedded Tomcat", ex);
}
}
}備注： 在這個過程中我們需要了解Bean的生命周期，Tomcat的三個定制器均在BeanPostProcessorsRegistrar（Bean后置處理器）過程中加載；
構(gòu)造方法-->Bean后置處理器Before-->InitializingBean-->init-method-->Bean后置處理器After
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#doCreateBean org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#initializeBean
protected Object doCreateBean(final String beanName, final RootBeanDefinition mbd, final @Nullable Object[] args)
throws BeanCreationException {
// Instantiate the bean.
BeanWrapper instanceWrapper = null;
if (mbd.isSingleton()) {
instanceWrapper = this.factoryBeanInstanceCache.remove(beanName);
}
if (instanceWrapper == null) {
//構(gòu)造方法
instanceWrapper = createBeanInstance(beanName, mbd, args);
}
final Object bean = instanceWrapper.getWrappedInstance();
Class beanType = instanceWrapper.getWrappedClass();
if (beanType != NullBean.class) {
mbd.resolvedTargetType = beanType;
}
// Initialize the bean instance.
......
return exposedObject;
}
protected Object initializeBean(final String beanName, final Object bean, @Nullable RootBeanDefinition mbd) {
if (System.getSecurityManager() != null) {
AccessController.doPrivileged((PrivilegedAction以上就是關(guān)于“springboot中如何利用Tomcat容器實現(xiàn)自啟動”這篇文章的內(nèi)容，相信大家都有了一定的了解，希望小編分享的內(nèi)容對大家有幫助，若想了解更多相關(guān)的知識內(nèi)容，請關(guān)注創(chuàng)新互聯(lián)行業(yè)資訊頻道。
