欧美bbbwbbbw肥妇,免费乱码人妻系列日韩,一级黄片

Spring Boot啟動(dòng)過程(六)之內(nèi)嵌Tomcat中StandardHost、StandardContext和StandardWrapper的啟動(dòng)教程詳解

 更新時(shí)間:2017年04月22日 17:38:53   作者:draculav  
這篇文章主要介紹了Spring Boot啟動(dòng)過程(六)之內(nèi)嵌Tomcat中StandardHost、StandardContext和StandardWrapper的啟動(dòng)教程詳解,需要的朋友可以參考下

 StandardEngine[Tomcat].StandardHost[localhost]的啟動(dòng)與StandardEngine不在同一個(gè)線程中,它的start:   

// Start our child containers, if any
  Container children[] = findChildren();
  List<Future<Void>> results = new ArrayList<>();
  for (int i = 0; i < children.length; i++) {
   results.add(startStopExecutor.submit(new StartChild(children[i])));
  }
  boolean fail = false;
  for (Future<Void> result : results) {
   try {
    result.get();
   } catch (Exception e) {
    log.error(sm.getString("containerBase.threadedStartFailed"), e);
    fail = true;
   }
  }
  if (fail) {
   throw new LifecycleException(
     sm.getString("containerBase.threadedStartFailed"));
  }
 private static class StartChild implements Callable<Void> {
  private Container child;
  public StartChild(Container child) {
   this.child = child;
  }
  @Override
  public Void call() throws LifecycleException {
   child.start();
   return null;
  }
 }

  這個(gè)start流程中,initInternal方法是ContainerBase的代碼,還是那個(gè)初始化startStopExecutor的,線程名例如Thread[localhost-startStop-1,5,main],這次是用來初始化host的子容器的,然后是StandardHost中的startInternal方法,主要是注冊(cè)了一個(gè)errorValue,如果現(xiàn)有的pipeline中沒有errorvalue,則反射創(chuàng)建org.apache.catalina.valves.ErrorReportValve實(shí)例,并加入pipeline中,容器pipeline加入Value時(shí)會(huì)發(fā)布一個(gè)Container.ADD_VALVE_EVENT事件,與engine一樣,之后進(jìn)入ContainerBase的startInternal,但是這次Realm是null不需要啟動(dòng),然后findChildren出StandardEngine[Tomcat]. StandardHost [localhost].StandardContext[],然后同樣新開個(gè)線程new StartChild,start同樣是上面的代碼,需要特別說明的是,這次before_init的事件有監(jiān)聽的了,F(xiàn)ixContextListener,DisablePersistSessionListener,MemoryLeakTrackingListener;FixContextListener監(jiān)聽的處理,會(huì)加入一個(gè)用于不做用戶身份認(rèn)證的安全檢查的Value:               

Context context = (Context) event.getLifecycle();
    if (event.getType().equals(Lifecycle.CONFIGURE_START_EVENT)) {
     context.setConfigured(true);
    }
    // LoginConfig is required to process @ServletSecurity
    // annotations
    if (context.getLoginConfig() == null) {
     context.setLoginConfig(
       new LoginConfig("NONE", null, null, null));
     context.getPipeline().addValve(new NonLoginAuthenticator());
    }

   DisablePersistSessionListener監(jiān)聽只處理start事件,所以這里只判斷了一下發(fā)現(xiàn)不是就出去了,其實(shí)這里可以思考下,有沒有更好的辦法,讓監(jiān)聽不只是廣播方式,能不能用訂閱方式,先不細(xì)想了,接著看代碼,MemoryLeakTrackingListener只監(jiān)聽了after_start事件,這步同樣什么都沒做。

  于是來到了StandardContext的initInternal,它的super.initInternal又是一個(gè)startStopExecutor,ContainerBase的super.initInternal就不再說了,發(fā)送j2ee.object.created消息:         

Notification notification = new Notification("j2ee.object.created",
     this.getObjectName(), sequenceNumber.getAndIncrement());
   broadcaster.sendNotification(notification);

   Notification是EventObject的子類,代表由MBean發(fā)出的通知,MBean server發(fā)出的通知會(huì)包含發(fā)出的MBean的引用,如果MBean注冊(cè)了監(jiān)聽,可以通過object name或引用獲取消息發(fā)出者,官方建議使用object name;sendNotification方法:

 /**
  * Sends a notification.
  *
  * If an {@code Executor} was specified in the constructor, it will be given one
  * task per selected listener to deliver the notification to that listener.
  *
  * @param notification The notification to send.
  */
 public void sendNotification(Notification notification) {
  if (notification == null) {
   return;
  }
  boolean enabled;
  for (ListenerInfo li : listenerList) {
   try {
    enabled = li.filter == null ||
     li.filter.isNotificationEnabled(notification);
   } catch (Exception e) {
    if (logger.debugOn()) {
     logger.debug("sendNotification", e);
    }
    continue;
   }
   if (enabled) {
    executor.execute(new SendNotifJob(notification, li));
   }
  }
 }

  發(fā)完消息就轉(zhuǎn)變狀態(tài)為初始化完成,因?yàn)楸O(jiān)聽器是注冊(cè)在context容器上的,于是after_init事件又觸發(fā)了那三個(gè)監(jiān)聽器,這一階段監(jiān)聽器什么都沒處理走了下過場而已;before_start同走過場;然后StandardContext的startInternal方法,發(fā)布了個(gè)j2ee.state.starting消息object name為Tomcat:j2eeType=WebModule,name=//localhost/,J2EEApplication=none, J2EEServer=none;setConfigured(false)還沒有正確的配置;設(shè)置WebResourceRoot,WebResourceRoot提供整個(gè)應(yīng)用資源處理類的各種方法,內(nèi)嵌用的實(shí)現(xiàn)類是StandardRoot,set的過程中加了寫鎖:        

try {
    setResources(new StandardRoot(this));
   } catch (IllegalArgumentException e) {
    log.error(sm.getString("standardContext.resourcesInit"), e);
    ok = false;
   }

   StandardRoot的屬性allResources:

private final List<List<WebResourceSet>> allResources =
   new ArrayList<>();
 {
  allResources.add(preResources);
  allResources.add(mainResources);
  allResources.add(classResources);
  allResources.add(jarResources);
  allResources.add(postResources);
 }

  http://tomcat.apache.org/tomcat-8.0-doc/api/org/apache/catalina/WebResourceRoot.html有相關(guān)說明,我就不翻譯了。

  set之后就是啟動(dòng)resourcesStart,initInternal執(zhí)行的是StandardRoot的initInternal方法,super.initInternal中依然是那兩行代碼,register(cache, getObjectNameKeyProperties() + ",name=Cache")會(huì)發(fā)送MBeanServerNotification. REGISTRATION_NOTIFICATION通知,生成ObjectName這里cacheJmxName是Tomcat:type=WebResourceRoot,host=localhost,context=/,name=Cache;registerURLStreamHandlerFactory里面的代碼是TomcatURLStreamHandlerFactory.register()這行代碼的注釋說這是為了支持war包內(nèi)的jar資源的。之后是循環(huán)上面的allResources,init里面加入的webResourceSet,但是由于全都是空的,所以等于沒執(zhí)行,就不說了,回頭再仔細(xì)看看什么情況下回不為空,還是內(nèi)嵌的就是空的。createMainResourceSet主要是設(shè)置個(gè)主目錄,例如/tmp/tomcat-docbase.3031819619941848514.80,然后是各種資源該放在哪個(gè)子目錄的一些設(shè)置代碼;這次資源有一個(gè)了,所以可以有一個(gè)start了,DirResourceSet的;super.initInternal()的super是AbstractFileResourceSet:

 //-------------------------------------------------------- Lifecycle methods
 @Override
 protected void initInternal() throws LifecycleException {
  super.initInternal();
  // Is this an exploded web application?
  if (getWebAppMount().equals("")) {
   // Look for a manifest
   File mf = file("META-INF/MANIFEST.MF", true);
   if (mf != null && mf.isFile()) {
    try (FileInputStream fis = new FileInputStream(mf)) {
     setManifest(new Manifest(fis));
    } catch (IOException e) {
     log.warn(sm.getString("dirResourceSet.manifestFail", mf.getAbsolutePath()), e);
    }
   }
  }
 }

  super.initInternal主要是對(duì)base目錄進(jìn)行了一些規(guī)范化處理,規(guī)范的方法主要是UnixFileSystem中的canonicalize其中還使用ExpiringCache對(duì)路徑做了緩存,另外還有在normalize方法中對(duì)路徑中類似"\.."的部分做了處理。WebAppMount是Web應(yīng)用發(fā)布資源的位置,必須以‘/'開頭,這里應(yīng)該是通過它來判斷不是war包部署的模式,然后由于manifest沒找到,所以方法返回初始化完成,這個(gè)資源一路狀態(tài)變化就啟動(dòng)完了。

  回到StandardRoot,接下來是processWebInfLib方法,代碼很直觀,不解釋了:

private void processWebInfLib() {
  WebResource[] possibleJars = listResources("/WEB-INF/lib", false);
  for (WebResource possibleJar : possibleJars) {
   if (possibleJar.isFile() && possibleJar.getName().endsWith(".jar")) {
    createWebResourceSet(ResourceSetType.CLASSES_JAR,
      "/WEB-INF/classes", possibleJar.getURL(), "/");
   }
  }
 }

  接下來也不解釋:

 // Need to start the newly found resources
  for (WebResourceSet classResource : classResources) {
   classResource.start();
  }

  cache.enforceObjectMaxSizeLimit是計(jì)算緩存限制的,詳細(xì)的可以參考http://tomcat.apache.org/tomcat-8.0-doc/config/resources.html,至此StandardRoot的啟動(dòng)完成就只剩下改狀態(tài)了。

  回到StandardContext,因?yàn)閏lassloader已經(jīng)有了不需要new了;接著創(chuàng)建Rfc6265CookieProcessor類型的cookieProcessor實(shí)例,關(guān)于Rfc6265標(biāo)準(zhǔn)參考http://www.rfc-editor.org/rfc/rfc6265.txt;character set mapper因?yàn)橐呀?jīng)初始化好了只判斷了下;工作目錄處理,先根據(jù)host和engine名生成路徑如:work/Tomcat/localhost/ROOT,結(jié)合前面的base創(chuàng)建目錄例如/tmp/tomcat.3726907762383543267.80/work/Tomcat/localhost/ROOT,然后初始化StandardContext中的ApplicationContext類型可繼承的全局變量context構(gòu)造用參數(shù)是this(context = new ApplicationContext(this)),返回new ApplicationContextFacade(this);將上面的全路徑設(shè)置給ServletContext.TEMPDIR屬性,并將這個(gè)屬性設(shè)置為只讀:

 /**
  * Set an attribute as read only.
  */
 void setAttributeReadOnly(String name) {
  if (attributes.containsKey(name))
   readOnlyAttributes.put(name, name);
 }

  之后是對(duì)擴(kuò)展進(jìn)行驗(yàn)證,這里說一下,StandardContext中不管是這里的獲取資源還是之后的讀取classloader都是加了讀鎖的:

 // Validate required extensions
  boolean dependencyCheck = true;
  try {
   dependencyCheck = ExtensionValidator.validateApplication
    (getResources(), this);
  } catch (IOException ioe) {
   log.error(sm.getString("standardContext.extensionValidationError"), ioe);
   dependencyCheck = false;
  }

  catalina.useNaming用于是否開啟命名服務(wù)支持,開啟了就會(huì)注冊(cè)NamingContextListener監(jiān)聽器:

if (!dependencyCheck) {
   // do not make application available if depency check fails
   ok = false;
  }
  // Reading the "catalina.useNaming" environment variable
  String useNamingProperty = System.getProperty("catalina.useNaming");
  if ((useNamingProperty != null)
   && (useNamingProperty.equals("false"))) {
   useNaming = false;
  }
  if (ok && isUseNaming()) {
   if (getNamingContextListener() == null) {
    NamingContextListener ncl = new NamingContextListener();
    ncl.setName(getNamingContextName());
    ncl.setExceptionOnFailedWrite(getJndiExceptionOnFailedWrite());
    addLifecycleListener(ncl);
    setNamingContextListener(ncl);
   }
  }

  ClassLoader oldCCL = bindThread()里有個(gè)ThreadBindingListener,不過因?yàn)閣ebApplicationClassLoader是null,所以等于沒執(zhí)行,返回的是null,里面的邏輯還不少,命名服務(wù)也沒開ContextBindings.bindThread于是也沒執(zhí)行。

  old的沒有,但是loader還是有的,到了loader的start了,主要要說的是WebappLoader的startInternal方法,classloader創(chuàng)建:       

 classLoader = createClassLoader();
   classLoader.setResources(context.getResources());
   classLoader.setDelegate(this.delegate);

  buildClassPath的主要功能是遍歷各個(gè)層次的classloader并將其中classpath的jar拼成一個(gè)字符串,例如
:/usr/lib/jvm/java-8-oracle/jre/lib/charsets.jar:/usr/lib/jvm/java-8-oracle/jre/lib/deploy.jar:/usr/lib/jvm/java-8-oracle/jre/lib/ext/cldrdata.jar...,是以':'作為分隔是因?yàn)槲业拈_發(fā)環(huán)境是linux,在windows中應(yīng)該是';':

 while (loader != null) {
   if (!buildClassPath(classpath, loader)) {
    break;
   }
   loader = loader.getParent();
  }
  if (delegate) {
   // Delegation was enabled, go back and add the webapp paths
   loader = getClassLoader();
   if (loader != null) {
    buildClassPath(classpath, loader);
   }
  }

         delegate之前提過了,是會(huì)向基loader類委托的;setClassPath的最后一句:servletContext.setAttribute(Globals.CLASS_PATH_ATTR, this.classpath)。

  setPermissions方法,由于我這第一個(gè)判斷就返回了,而且看上去代碼也很直觀,我就不說了:

private void setPermissions() {
  if (!Globals.IS_SECURITY_ENABLED)
   return;
  if (context == null)
   return;
  // Tell the class loader the root of the context
  ServletContext servletContext = context.getServletContext();
  // Assigning permissions for the work directory
  File workDir =
   (File) servletContext.getAttribute(ServletContext.TEMPDIR);
  if (workDir != null) {
   try {
    String workDirPath = workDir.getCanonicalPath();
    classLoader.addPermission
     (new FilePermission(workDirPath, "read,write"));
    classLoader.addPermission
     (new FilePermission(workDirPath + File.separator + "-",
          "read,write,delete"));
   } catch (IOException e) {
    // Ignore
   }
  }
  for (URL url : context.getResources().getBaseUrls()) {
   classLoader.addPermission(url);
  }
 }

      ((Lifecycle) classLoader).start(),這個(gè)classloader是TomcatEmbeddedWebappClassLoader走的是WebappClassLoaderBase中的start方法,這里因?yàn)槭莾?nèi)嵌的版本(我沒確認(rèn),猜測)所以也并沒有加載到東西,所以也不細(xì)說了:

 public void start() throws LifecycleException {
  state = LifecycleState.STARTING_PREP;
  WebResource classes = resources.getResource("/WEB-INF/classes");
  if (classes.isDirectory() && classes.canRead()) {
   localRepositories.add(classes.getURL());
  }
  WebResource[] jars = resources.listResources("/WEB-INF/lib");
  for (WebResource jar : jars) {
   if (jar.getName().endsWith(".jar") && jar.isFile() && jar.canRead()) {
    localRepositories.add(jar.getURL());
    jarModificationTimes.put(
      jar.getName(), Long.valueOf(jar.getLastModified()));
   }
  }
  state = LifecycleState.STARTED;
 }

  然后生成ObjectName例如:Tomcat:context=/,host=localhost,type=TomcatEmbeddedWebappClassLoader,然后注冊(cè)MBean:getMBeanServer().registerMBean( mbean, oname);WebappLoader的start就沒什么了,started之后就是設(shè)置了幾個(gè)屬性:

 // since the loader just started, the webapp classloader is now
    // created.
    setClassLoaderProperty("clearReferencesRmiTargets",
      getClearReferencesRmiTargets());
    setClassLoaderProperty("clearReferencesStopThreads",
      getClearReferencesStopThreads());
    setClassLoaderProperty("clearReferencesStopTimerThreads",
      getClearReferencesStopTimerThreads());
    setClassLoaderProperty("clearReferencesHttpClientKeepAliveThread",
      getClearReferencesHttpClientKeepAliveThread());

  這里的unbindThread因?yàn)榍懊娴腷ind幾乎沒做什么,所以什么也沒做;接著的bindThread主要講線程與classloader做了綁定: Thread.currentThread().setContextClassLoader (webApplicationClassLoader),至于threadBindingListener.bind()由于threadBindingListener用了個(gè)空實(shí)現(xiàn),所以這里什么也沒做。

  接下來用讀鎖取到Realm并start它;接下來發(fā)布configure_start事件,F(xiàn)ixContextListener中執(zhí)行了context.setConfigured(true)。

  終于到了StandardWrapper(StandardEngine[Tomcat].StandardHost[localhost].StandardContext[].StandardWrapper[default])的start了,initInternal直接就是ContainerBase的初始化startStopExecutor,startInternal方法是發(fā)了個(gè)j2ee.state.starting的消息,ObjectName是Tomcat:j2eeType=Servlet, WebModule=//localhost/, name=default, J2EEApplication=none, J2EEServer=none,然后又到ContainerBase的startInternal,然而由于它沒有子容器了,所以這里并沒有StartChild的任務(wù)產(chǎn)生;于是開始執(zhí)行它的Value,先start它的pipeline,startInternal方法依然是StandardPipeline的,按順序start,由于到這的時(shí)候一個(gè)都沒有,所以執(zhí)行的是basic的,StandardWrapperValve的initInternal中只有一句注釋:Don't register this Valve in JMX;startInternal的最后是threadStart,但由于backgroundProcessorDelay是-1所以并沒有啟動(dòng)背景線程;setAvailable(0L)設(shè)置可用,它的說明 The date and time at which this servlet will become available (in milliseconds since the epoch), or zero if the servlet is available;然后發(fā)送一個(gè)消息j2ee.state.running,ObjectName是Tomcat:j2eeType=Servlet,WebModule=//localhost/,name=default,J2EEApplication=none,J2EEServer=none;

  StandardWrapper就啟動(dòng)完了,回到StandardContext,start它的pipeline;與StandardWrapper的pipeline不同,它之前被注冊(cè)過NonLoginAuthenticator,它的startInternal方法定義在AuthenticatorBase,方法中設(shè)置了jaspicAppContextID(例如:Tomcat/localhost ),然后獲取上級(jí)容器也就是host的pipeline中的所有Value,并找到其中SingleSignOn類型的Value,明顯是用于單點(diǎn)登錄的,我這里沒有,于是又去找了上一級(jí)容器engine當(dāng)然還是沒有,于是就往下走了;實(shí)例化了一個(gè)StandardSessionIdGenerator,設(shè)置安全隨機(jī)數(shù)生成算法我這里是SHA1PRNG,生成器類名為null,生成器provider也是null,然后就是下一個(gè)Value對(duì)象StandardContextValve的start,只不過它的start是標(biāo)準(zhǔn)的什么額外事都沒干,于是回到了StandardContext中。下面一段主要是執(zhí)行了TomcatEmbeddedContext中的setManager方法:

@Override
 public void setManager(Manager manager) {
  if (manager instanceof ManagerBase) {
   ((ManagerBase) manager).setSessionIdGenerator(new LazySessionIdGenerator());
  }
  super.setManager(manager);
 }

  這里判斷是true,LazySessionIdGenerator整個(gè)的代碼:

class LazySessionIdGenerator extends StandardSessionIdGenerator {

@Override
 protected void startInternal() throws LifecycleException {
  setState(LifecycleState.STARTING);
 }
}

  TomcatEmbeddedContext的super.setManager(manager)的super是StandardContext,在寫鎖中執(zhí)行的,spring中多數(shù)的set都是交換的方式,先set個(gè)old保存下來,然后判斷新值和old是否相同,不相同用新的并將新值綁定容器,相同直接返回;getServletContext().setAttribute(Globals.RESOURCES_ATTR, getResources())沒什么好解釋的;setNamingResources(new NamingResourcesImpl());然后init這個(gè)namingResources,NamingResourcesImpl的initInternal,在設(shè)置當(dāng)前已知命名資源前設(shè)置resourceRequireExplicitRegistration用于避免時(shí)序問題,重復(fù)注冊(cè)是正常的,后面一段我不想解釋:

 for (ContextResource cr : resources.values()) {
   try {
    MBeanUtils.createMBean(cr);
   } catch (Exception e) {
    log.warn(sm.getString(
      "namingResources.mbeanCreateFail", cr.getName()), e);
   }
  }
  for (ContextEnvironment ce : envs.values()) {
   try {
    MBeanUtils.createMBean(ce);
   } catch (Exception e) {
    log.warn(sm.getString(
      "namingResources.mbeanCreateFail", ce.getName()), e);
   }
  }
  for (ContextResourceLink crl : resourceLinks.values()) {
   try {
    MBeanUtils.createMBean(crl);
   } catch (Exception e) {
    log.warn(sm.getString(
      "namingResources.mbeanCreateFail", crl.getName()), e);
   }
  }

        init之后是start,start中只發(fā)布了個(gè)configure_start事件。

  setInstanceManager(new DefaultInstanceManager(context, injectionMap, this, this.getClass().getClassLoader())),InstanceManager主要是用于創(chuàng)建和回收實(shí)例,然后綁定:         

 getServletContext().setAttribute(
      InstanceManager.class.getName(), getInstanceManager());
    InstanceManagerBindings.bind(getLoader().getClassLoader(), getInstanceManager());

  還有:            

 getServletContext().setAttribute(
      JarScanner.class.getName(), getJarScanner());

  合并參數(shù)mergeParameters由于我這里是空的,所以什么也沒做;然后遍歷initializers并onStartup:

  先是進(jìn)入到TomcatStarter的onStartup,這里又是:     

 for (ServletContextInitializer initializer : this.initializers) {
    initializer.onStartup(servletContext);
   }

  先是執(zhí)行:   

private org.springframework.boot.web.servlet.ServletContextInitializer getSelfInitializer() {
  return new ServletContextInitializer() {
   @Override
   public void onStartup(ServletContext servletContext) throws ServletException {
    selfInitialize(servletContext);
   }
  };
 }

  EmbeddedWebApplicationContext中的selfInitialize ,prepareEmbeddedWebApplicationContext正常情況下先打一條日志Initializing Spring embedded WebApplicationContext然后servletContext.setAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE, this)然后將this綁定servletContext,如果啟動(dòng)Info級(jí)別日志,會(huì)打印類似這樣的日志:Root WebApplicationContext: initialization completed in 3150193 ms;然后new ExistingWebApplicationScopes,這玩意的注釋說它允許與非嵌入式相同的方式注冊(cè)作用域到ApplicationContextInitializer,先執(zhí)行了一個(gè)靜態(tài)代碼塊:   

 static {
   Set<String> scopes = new LinkedHashSet<String>();
   scopes.add(WebApplicationContext.SCOPE_REQUEST);//request
   scopes.add(WebApplicationContext.SCOPE_SESSION);//session
   scopes.add(WebApplicationContext.SCOPE_GLOBAL_SESSION);//global session
   SCOPES = Collections.unmodifiableSet(scopes);
  }

  但是似乎在我這add白做了,因?yàn)闃?gòu)造函數(shù)中從bean工廠并沒取到Scope實(shí)例:     

this.beanFactory = beanFactory;
   for (String scopeName : SCOPES) {
    Scope scope = beanFactory.getRegisteredScope(scopeName);
    if (scope != null) {
     this.scopes.put(scopeName, scope);
    }
   }

   真正注冊(cè)作用域是在下一句WebApplicationContextUtils.registerWebApplicationScopes(beanFactory, getServletContext()):  

 beanFactory.registerScope(WebApplicationContext.SCOPE_REQUEST, new RequestScope());
  beanFactory.registerScope(WebApplicationContext.SCOPE_SESSION, new SessionScope(false));
  beanFactory.registerScope(WebApplicationContext.SCOPE_GLOBAL_SESSION, new SessionScope(true));
  if (sc != null) {
   ServletContextScope appScope = new ServletContextScope(sc);
   beanFactory.registerScope(WebApplicationContext.SCOPE_APPLICATION, appScope);
   // Register as ServletContext attribute, for ContextCleanupListener to detect it.
   sc.setAttribute(ServletContextScope.class.getName(), appScope);
  }
  beanFactory.registerResolvableDependency(ServletRequest.class, new RequestObjectFactory());
  beanFactory.registerResolvableDependency(ServletResponse.class, new ResponseObjectFactory());
  beanFactory.registerResolvableDependency(HttpSession.class, new SessionObjectFactory());
  beanFactory.registerResolvableDependency(WebRequest.class, new WebRequestObjectFactory());
  if (jsfPresent) {
   FacesDependencyRegistrar.registerFacesDependencies(beanFactory);
  }

  registerResolvableDependency將類型與對(duì)應(yīng)的裝配對(duì)象注冊(cè)進(jìn)bean工廠。existingScopes.restore里的代碼:      

public void restore() {
   for (Map.Entry<String, Scope> entry : this.scopes.entrySet()) {
    if (logger.isInfoEnabled()) {
     logger.info("Restoring user defined scope " + entry.getKey());
    }
    this.beanFactory.registerScope(entry.getKey(), entry.getValue());
   }
  }

  WebApplicationContextUtils.registerEnvironmentBeans(beanFactory, getServletContext())把相應(yīng)的變量key與值注冊(cè)給bean工廠,如servletContext、contextParameters和contextAttributes;從bean工廠中獲取所有org.springframework.boot.web.servlet.ServletContextInitializer類型的bean,如filterRegistrationBean和dispatcherServletRegistration然后add給ServletContextInitializerBeans實(shí)例的initializers;addAdaptableBeans方法先從bean工廠中獲取javax.servlet.MultipartConfigElement類型的對(duì)象,然而javax.servlet.Servlet沒在bean工廠里找到,所以add什么也沒做;javax.servlet.Filter找到characterEncodingFilter、hiddenHttpMethodFilter、httpPutFormContentFilter、requestContextFilter;ServletListenerRegistrationBean.getSupportedTypes()取的是ServletListenerRegistrationBean的SUPPORTED_TYPES,不過全都沒找到,所以什么也沒做:

 static {
  Set<Class<?>> types = new HashSet<Class<?>>();
  types.add(ServletContextAttributeListener.class);
  types.add(ServletRequestListener.class);
  types.add(ServletRequestAttributeListener.class);
  types.add(HttpSessionAttributeListener.class);
  types.add(HttpSessionListener.class);
  types.add(ServletContextListener.class);
  SUPPORTED_TYPES = Collections.unmodifiableSet(types);
 }

  然后是對(duì)找到的進(jìn)行排序:     

List<ServletContextInitializer> sortedInitializers = new ArrayList<ServletContextInitializer>();
  for (Map.Entry<?, List<ServletContextInitializer>> entry : this.initializers
    .entrySet()) {
   AnnotationAwareOrderComparator.sort(entry.getValue());
   sortedInitializers.addAll(entry.getValue());
  }
  this.sortedList = Collections.unmodifiableList(sortedInitializers);
 public static void sort(Object[] array) {
  if (array.length > 1) {
   Arrays.sort(array, INSTANCE);
  }
 }
 private int doCompare(Object o1, Object o2, OrderSourceProvider sourceProvider) {
  boolean p1 = (o1 instanceof PriorityOrdered);
  boolean p2 = (o2 instanceof PriorityOrdered);
  if (p1 && !p2) {
   return -1;
  }
  else if (p2 && !p1) {
   return 1;
  }
  // Direct evaluation instead of Integer.compareTo to avoid unnecessary object creation.
  int i1 = getOrder(o1, sourceProvider);
  int i2 = getOrder(o2, sourceProvider);
  return (i1 < i2) ? -1 : (i1 > i2) ? 1 : 0;
 }

  然后對(duì)這些初始化器進(jìn)行beans.onStartup(servletContext);filterRegistrationBean執(zhí)行的AbstractFilterRegistrationBean的,主要執(zhí)行了這兩句:

        FilterRegistration.Dynamic added = servletContext.addFilter(name, filter);
                ...
        configure(added);
  name:characterEncodingFilter,filter:OrderedCharacterEncodingFilter,它的配置中這里設(shè)定了過濾器轉(zhuǎn)發(fā)模式有FORWARD、INCLUDE、REQUEST、ASYNC,攔截路徑:"/*";然后是hiddenHttpMethodFilter和OrderedHiddenHttpMethodFilter,httpPutFormContentFilter和OrderedHttpPutFormContentFilter,requestContextFilter和OrderedRequestContextFilter,cipherFilter和CipherFilter(我這自定義的)。ServletRegistrationBean的:dispatcherServlet和DispatcherServlet,asyncSupported是true,url映射是‘/',設(shè)置StandardWrapper的loadOnStartup、 multipartConfigElement。

  到了下一個(gè)初始化器SessionConfiguringInitializer:      

 public void onStartup(ServletContext servletContext) throws ServletException {
   if (this.session.getTrackingModes() != null) {
    servletContext.setSessionTrackingModes(this.session.getTrackingModes());
   }
   configureSessionCookie(servletContext.getSessionCookieConfig());
  }

  將session中的cookie信息補(bǔ)充進(jìn)ApplicationSessionCookieConfig的實(shí)例中,例如:           

 config.setName(cookie.getName());
    config.setDomain(cookie.getDomain());
    config.setPath(cookie.getPath());
    config.setComment(cookie.getComment());
    config.setHttpOnly(cookie.getHttpOnly());
    config.setSecure(cookie.getSecure());
    config.setMaxAge(cookie.getMaxAge());

  實(shí)際中我這里一個(gè)都沒執(zhí)行,因?yàn)槲疫@的session中cookie信息都是null。

  下一個(gè)初始化器InitParameterConfiguringServletContextInitializer由于參數(shù)沒有,所以進(jìn)去就出來了。

  回到listenerStart,listenerStart:org.apache.tomcat.websocket.server.WsContextListener,用前面的DefaultInstanceManager的newInstance創(chuàng)建,然后加到lifecycleListeners中,然后傳給applicationLifecycleListenersObjects,然后是newServletContextListenerAllowed=false:當(dāng)listener發(fā)生調(diào)用后不允許添加,發(fā)布beforeContextInitialized事件,然后WsContextListener的contextInitialized:    

 ServletContext sc = sce.getServletContext();
  if(sc.getAttribute("javax.websocket.server.ServerContainer") == null) {
   WsSci.init(sce.getServletContext(), false);
  }

  init中先是初始化WsServerContainer:  

 static {
  GET_BYTES = "GET ".getBytes(StandardCharsets.ISO_8859_1);
  ROOT_URI_BYTES = "/".getBytes(StandardCharsets.ISO_8859_1);
  HTTP_VERSION_BYTES = " HTTP/1.1\r\n".getBytes(StandardCharsets.ISO_8859_1);
 }
 static {
  AUTHENTICATED_HTTP_SESSION_CLOSED = new CloseReason(CloseCodes.VIOLATED_POLICY, "This connection was established under an authenticated HTTP session that has ended.");
 }
 WsServerContainer(ServletContext servletContext) {
  this.enforceNoAddAfterHandshake = Constants.STRICT_SPEC_COMPLIANCE; //Boolean.getBoolean("org.apache.tomcat.websocket.STRICT_SPEC_COMPLIANCE")
  this.addAllowed = true;
  this.authenticatedSessions = new ConcurrentHashMap();
  this.endpointsRegistered = false;
  this.servletContext = servletContext;
   //我這里添加了org.apache.tomcat.websocket.server和本地語言en_US(我代碼是在英文版ubuntu上跑的)
  this.setInstanceManager((InstanceManager)servletContext.getAttribute(InstanceManager.class.getName())); 
  String value = servletContext.getInitParameter("org.apache.tomcat.websocket.binaryBufferSize");
  if(value != null) {
   this.setDefaultMaxBinaryMessageBufferSize(Integer.parseInt(value));
  }
  value = servletContext.getInitParameter("org.apache.tomcat.websocket.textBufferSize");
  if(value != null) {
   this.setDefaultMaxTextMessageBufferSize(Integer.parseInt(value));
  }
    //Java WebSocket 規(guī)范 1.0 并不允許第一個(gè)服務(wù)端點(diǎn)開始 WebSocket 握手之后進(jìn)行程序性部署。默認(rèn)情況下,Tomcat 繼續(xù)允許額外的程序性部署。
  value = servletContext.getInitParameter("org.apache.tomcat.websocket.noAddAfterHandshake");
  if(value != null) {
   this.setEnforceNoAddAfterHandshake(Boolean.parseBoolean(value));
  }
  Dynamic fr = servletContext.addFilter("Tomcat WebSocket (JSR356) Filter", new WsFilter());
  fr.setAsyncSupported(true);
  EnumSet types = EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD);
  fr.addMappingForUrlPatterns(types, true, new String[]{"/*"});
 }

  init創(chuàng)建了 WsServerContainer之后,將它設(shè)置給servletContext的javax.websocket.server.ServerContainer屬性,然后servletContext.addListener(new WsSessionListener(sc))加進(jìn)前面的applicationLifecycleListenersObjects中,init結(jié)束,回到StandardContext發(fā)布afterContextInitialized事件,我這到這里listenerStart結(jié)束。

  checkConstraintsForUncoveredMethods(findConstraints())因?yàn)槲疫@里find出來的并沒有,所以pass;start StandardManager startInternal先是super(ManagerBase),一進(jìn)方法先是將兩個(gè)雙端隊(duì)列sessionCreationTiming和sessionExpirationTiming根據(jù)常量TIMING_STATS_CACHE_SIZE用null填滿,設(shè)置jvmRoute(jvmRoute用于區(qū)分多tomcat節(jié)點(diǎn),根據(jù)jvmRoute的值來確定當(dāng)前會(huì)話屬于哪個(gè)節(jié)點(diǎn) ),從engine上取得,之前設(shè)置過,getEngine: 

 public Engine getEngine() {
  Engine e = null;
  for (Container c = getContext(); e == null && c != null ; c = c.getParent()) {
   if (c instanceof Engine) {
    e = (Engine)c;
   }
  }
  return e;
 }

  set給sessionIdGenerator,將之前初始化過的一些sessionIdGenerator值set給新new的SessionIdGeneratorBase,然后start之前的sessionIdGenerator,這個(gè)start沒做什么特別的,于是回到StandardManager,加載文件(例:/tmp/tomcat.7550276477249965168.80/work/Tomcat/localhost/ROOT/SESSIONS.ser),用于session持久化的,這時(shí)候找不到的。

  filterStart對(duì)filterConfigs同步鎖,filterConfigs.put(name, filterConfig):

  loadOnStartup(findChildren()),其實(shí)都一起start過了就不用了:

   該啟動(dòng)StandardContext的后天線程了super.threadStart(),當(dāng)然因?yàn)閎ackgroundProcessorDelay所以也沒啟,unbindThread說是解綁,其實(shí)只是把classloader還原了,別的沒做什么,對(duì)應(yīng)著之前的bind。

  設(shè)置StandardContext的startTime=System.currentTimeMillis(),發(fā)j2ee.state.running的通知,ObjectName是Tomcat:J2EEApplication=none, J2EEServer=none, j2eeType=WebModule, name=//localhost/;getResources().gc()因?yàn)閃ebResources引用了一些jar,有些平臺(tái)可能會(huì)對(duì)jar加鎖,這里先清理,但實(shí)際上這里的實(shí)現(xiàn)是空的。

   DisablePersistSessionListener由于并沒有配置session持久化,所以會(huì)觸發(fā)這個(gè)監(jiān)聽器,實(shí)際只執(zhí)行了((StandardManager) manager).setPathname(null)。MemoryLeakTrackingListener只走了個(gè)過場。

   發(fā)布after_start事件,這回終于執(zhí)行了MemoryLeakTrackingListener:      

 if (event.getType().equals(Lifecycle.AFTER_START_EVENT)) {
    if (event.getSource() instanceof Context) {
     Context context = ((Context) event.getSource());
     childClassLoaders.put(context.getLoader().getClassLoader(),
       context.getServletContext().getContextPath());
    }
   }

  子容器就啟動(dòng)完成了。

咱最近用的github:https://github.com/saaavsaaa

以上所述是小編給大家介紹的Spring Boot啟動(dòng)過程(六)之內(nèi)嵌Tomcat中StandardHost、StandardContext和StandardWrapper的啟動(dòng)教程詳解,希望對(duì)大家有所幫助,如果大家有任何疑問請(qǐng)給我留言,小編會(huì)及時(shí)回復(fù)大家的。在此也非常感謝大家對(duì)腳本之家網(wǎng)站的支持!

相關(guān)文章

  • SpringBoot使用AOP實(shí)現(xiàn)防重復(fù)提交功能

    SpringBoot使用AOP實(shí)現(xiàn)防重復(fù)提交功能

    這篇文章主要為大家詳細(xì)介紹了SpringBoot如何使用AOP實(shí)現(xiàn)防重復(fù)提交功能,文中的示例代碼講解詳細(xì),感興趣的小伙伴可以跟隨小編一起學(xué)習(xí)一下
    2024-03-03
  • 超詳細(xì)的Java 問題排查工具單

    超詳細(xì)的Java 問題排查工具單

    這篇文章主要介紹了超詳細(xì)的Java 問題排查工具單,本文給大家介紹的非常詳細(xì),對(duì)大家的學(xué)習(xí)或工作具有一定的參考借鑒價(jià)值,需要的朋友可以參考下
    2021-01-01
  • Mybatis-Plus自動(dòng)填充更新操作相關(guān)字段的實(shí)現(xiàn)

    Mybatis-Plus自動(dòng)填充更新操作相關(guān)字段的實(shí)現(xiàn)

    數(shù)據(jù)庫表中應(yīng)該都要有create_time、update_time字段;那么在開發(fā)中,對(duì)于這些共有字段的處理應(yīng)該要進(jìn)行統(tǒng)一,這樣就可以簡化我們的開發(fā)過程。那么本文就對(duì)Mybatis-Plus中的字段自動(dòng)填充進(jìn)行記錄
    2021-11-11
  • Java利用Jackson序列化實(shí)現(xiàn)數(shù)據(jù)脫敏詳解

    Java利用Jackson序列化實(shí)現(xiàn)數(shù)據(jù)脫敏詳解

    在項(xiàng)目中有些敏感信息不能直接展示,比如客戶手機(jī)號(hào)、身份證、車牌號(hào)等信息,展示時(shí)均需要進(jìn)行數(shù)據(jù)脫敏,防止泄露客戶隱私。本文將利用Jackson序列化實(shí)現(xiàn)數(shù)據(jù)脫敏,需要的可以參考一下
    2023-03-03
  • Java實(shí)現(xiàn)計(jì)算器設(shè)計(jì)

    Java實(shí)現(xiàn)計(jì)算器設(shè)計(jì)

    這篇文章主要為大家詳細(xì)介紹了Java實(shí)現(xiàn)計(jì)算器設(shè)計(jì),文中示例代碼介紹的非常詳細(xì),具有一定的參考價(jià)值,感興趣的小伙伴們可以參考一下
    2021-07-07
  • springboot中事務(wù)管理@Transactional的注意事項(xiàng)與使用場景

    springboot中事務(wù)管理@Transactional的注意事項(xiàng)與使用場景

    今天小編就為大家分享一篇關(guān)于springboot中事務(wù)管理@Transactional的注意事項(xiàng)與使用場景,小編覺得內(nèi)容挺不錯(cuò)的,現(xiàn)在分享給大家,具有很好的參考價(jià)值,需要的朋友一起跟隨小編來看看吧
    2019-04-04
  • rabbitmq五種模式詳解(含實(shí)現(xiàn)代碼)

    rabbitmq五種模式詳解(含實(shí)現(xiàn)代碼)

    這篇文章主要介紹了rabbitmq五種模式詳解(含實(shí)現(xiàn)代碼),本文給大家介紹的非常詳細(xì),對(duì)大家的學(xué)習(xí)或工作具有一定的參考借鑒價(jià)值,需要的朋友可以參考下
    2021-04-04
  • 用java實(shí)現(xiàn)學(xué)生信息管理系統(tǒng)

    用java實(shí)現(xiàn)學(xué)生信息管理系統(tǒng)

    這篇文章主要為大家詳細(xì)介紹了java實(shí)現(xiàn)學(xué)生信息管理系統(tǒng),文中示例代碼介紹的非常詳細(xì),具有一定的參考價(jià)值,感興趣的小伙伴們可以參考一下
    2019-09-09
  • Spring聲明式事務(wù)和@Aspect的攔截順序問題的解決

    Spring聲明式事務(wù)和@Aspect的攔截順序問題的解決

    本篇文章主要介紹了Spring聲明式事務(wù)和@Aspect的攔截順序問題的解決,小編覺得挺不錯(cuò)的,現(xiàn)在分享給大家,也給大家做個(gè)參考。一起跟隨小編過來看看吧
    2018-05-05
  • Idea中如何查看SpringSecurity各Filter信息

    Idea中如何查看SpringSecurity各Filter信息

    這篇文章主要介紹了Idea中如何查看SpringSecurity各Filter信息,具有很好的參考價(jià)值,希望對(duì)大家有所幫助。如有錯(cuò)誤或未考慮完全的地方,望不吝賜教
    2023-01-01

最新評(píng)論