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web/tomcat/tomcat配置解析

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Tomcat配置解析

server.xml解析

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catalina类下的load方法里面开始解析server.xml
由于使用的是SAX解析，所以只需要关注三个回调方法
    startElement
    characters
    endElement
    当然其他回调也需要关注一下

startElement

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@Override
    public void startElement(String namespaceURI, String localName, String qName, Attributes list)
            throws SAXException {
        boolean debug = log.isDebugEnabled();

        if (saxLog.isDebugEnabled()) {
            saxLog.debug("startElement(" + namespaceURI + "," + localName + "," + qName + ")");
        }
        // 把一个标签的属性解析出来经过系统属性替换后返回
        // Parse system properties
        list = updateAttributes(list);

        // Save the body text accumulated for our surrounding element
        // 保存这个bodyText，用于弹出使用
        bodyTexts.push(bodyText);
        bodyText = new StringBuilder();

        // the actual element name is either in localName or qName, depending on whether the parser is namespace aware
        String name = localName;
        if ((name == null) || (name.length() < 1)) {
            name = qName;
        }

        // Compute the current matching rule
        StringBuilder sb = new StringBuilder(match);
        if (match.length() > 0) {
            sb.append('/');
        }
        sb.append(name);
        match = sb.toString();
        if (debug) {
            log.debug("  New match='" + match + "'");
        }

        // Fire "begin" events for all relevant rules
        // 根据初始化时给定了一些匹配规则，所以，它对应server标签的规则全部取出
        List<Rule> rules = getRules().match(namespaceURI, match);
        matches.push(rules);
        if ((rules != null) && (rules.size() > 0)) {
            for (Rule value : rules) {
                //使用规则开始解析
                try {
                    Rule rule = value;
                    if (debug) {
                        log.debug("  Fire begin() for " + rule);
                    }
                    rule.begin(namespaceURI, name, list);
                } catch (Exception e) {
                    log.error("Begin event threw exception", e);
                    throw createSAXException(e);
                } catch (Error e) {
                    log.error("Begin event threw error", e);
                    throw e;
                }
            }
        } else {
            if (debug) {
                log.debug("  No rules found matching '" + match + "'.");
            }
        }

    }

characters

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@Override
public void characters(char buffer[], int start, int length) throws SAXException {

    if (saxLog.isDebugEnabled()) {
        saxLog.debug("characters(" + new String(buffer, start, length) + ")");
    }
//就是把标签中间的文本容放到指定的bodyText存储
    bodyText.append(buffer, start, length);

}

endElement

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@Override
  public void endElement(String namespaceURI, String localName, String qName)
          throws SAXException {

      boolean debug = log.isDebugEnabled();

      if (debug) {
          if (saxLog.isDebugEnabled()) {
              saxLog.debug("endElement(" + namespaceURI + "," + localName + "," + qName + ")");
          }
          log.debug("  match='" + match + "'");
          log.debug("  bodyText='" + bodyText + "'");
      }

      // Parse system properties
      bodyText = updateBodyText(bodyText);

      // the actual element name is either in localName or qName, depending
      // on whether the parser is namespace aware
      String name = localName;
      if ((name == null) || (name.length() < 1)) {
          name = qName;
      }

      // Fire "body" events for all relevant rules
      List<Rule> rules = matches.pop();
      if ((rules != null) && (rules.size() > 0)) {
          String bodyText = this.bodyText.toString().intern();
          for (Rule value : rules) {
              try {
                  Rule rule = value;
                  if (debug) {
                      log.debug("  Fire body() for " + rule);
                  }
                  rule.body(namespaceURI, name, bodyText);
              } catch (Exception e) {
                  log.error("Body event threw exception", e);
                  throw createSAXException(e);
              } catch (Error e) {
                  log.error("Body event threw error", e);
                  throw e;
              }
          }
      } else {
          if (debug) {
              log.debug("  No rules found matching '" + match + "'.");
          }
          if (rulesValidation) {
              log.warn("  No rules found matching '" + match + "'.");
          }
      }

      // Recover the body text from the surrounding element
      bodyText = bodyTexts.pop();

      // Fire "end" events for all relevant rules in reverse order
      if (rules != null) {
          for (int i = 0; i < rules.size(); i++) {
              int j = (rules.size() - i) - 1;
              try {
                  Rule rule = rules.get(j);
                  if (debug) {
                      log.debug("  Fire end() for " + rule);
                  }
                  rule.end(namespaceURI, name);
              } catch (Exception e) {
                  log.error("End event threw exception", e);
                  throw createSAXException(e);
              } catch (Error e) {
                  log.error("End event threw error", e);
                  throw e;
              }
          }
      }

      // Recover the previous match expression
      int slash = match.lastIndexOf('/');
      if (slash >= 0) {
          match = match.substring(0, slash);
      } else {
          match = "";
      }

  }

web.xml解析

Engine – > Host–>content

HostConfig

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protected void deployDirectory(ContextName cn, File dir) {


        long startTime = 0;
        // Deploy the application in this directory
        if( log.isInfoEnabled() ) {
            startTime = System.currentTimeMillis();
            log.info(sm.getString("hostConfig.deployDir",
                    dir.getAbsolutePath()));
        }

        Context context = null;
        File xml = new File(dir, Constants.ApplicationContextXml);
        File xmlCopy =
                new File(host.getConfigBaseFile(), cn.getBaseName() + ".xml");


        DeployedApplication deployedApp;
        boolean copyThisXml = isCopyXML();
        boolean deployThisXML = isDeployThisXML(dir, cn);

        try {
            if (deployThisXML && xml.exists()) {
                synchronized (digesterLock) {
                    try {
                        context = (Context) digester.parse(xml);
                    } catch (Exception e) {
                        log.error(sm.getString(
                                "hostConfig.deployDescriptor.error",
                                xml), e);
                        context = new FailedContext();
                    } finally {
                        digester.reset();
                        if (context == null) {
                            context = new FailedContext();
                        }
                    }
                }

                if (copyThisXml == false && context instanceof StandardContext) {
                    // Host is using default value. Context may override it.
                    copyThisXml = ((StandardContext) context).getCopyXML();
                }

                if (copyThisXml) {
                    Files.copy(xml.toPath(), xmlCopy.toPath());
                    context.setConfigFile(xmlCopy.toURI().toURL());
                } else {
                    context.setConfigFile(xml.toURI().toURL());
                }
            } else if (!deployThisXML && xml.exists()) {
                // Block deployment as META-INF/context.xml may contain security
                // configuration necessary for a secure deployment.
                log.error(sm.getString("hostConfig.deployDescriptor.blocked",
                        cn.getPath(), xml, xmlCopy));
                context = new FailedContext();
            } else {
                context = (Context) Class.forName(contextClass).getConstructor().newInstance();
            }

            Class<?> clazz = Class.forName(host.getConfigClass());
            LifecycleListener listener = (LifecycleListener) clazz.getConstructor().newInstance();
            context.addLifecycleListener(listener);

            context.setName(cn.getName());
            context.setPath(cn.getPath());
            context.setWebappVersion(cn.getVersion());
            context.setDocBase(cn.getBaseName());
            host.addChild(context);
        } catch (Throwable t) {
            ExceptionUtils.handleThrowable(t);
            log.error(sm.getString("hostConfig.deployDir.error",
                    dir.getAbsolutePath()), t);
        } finally {
            deployedApp = new DeployedApplication(cn.getName(),
                    xml.exists() && deployThisXML && copyThisXml);

            // Fake re-deploy resource to detect if a WAR is added at a later
            // point
            deployedApp.redeployResources.put(dir.getAbsolutePath() + ".war",
                    Long.valueOf(0));
            deployedApp.redeployResources.put(dir.getAbsolutePath(),
                    Long.valueOf(dir.lastModified()));
            if (deployThisXML && xml.exists()) {
                if (copyThisXml) {
                    deployedApp.redeployResources.put(
                            xmlCopy.getAbsolutePath(),
                            Long.valueOf(xmlCopy.lastModified()));
                } else {
                    deployedApp.redeployResources.put(
                            xml.getAbsolutePath(),
                            Long.valueOf(xml.lastModified()));
                    // Fake re-deploy resource to detect if a context.xml file is
                    // added at a later point
                    deployedApp.redeployResources.put(
                            xmlCopy.getAbsolutePath(),
                            Long.valueOf(0));
                }
            } else {
                // Fake re-deploy resource to detect if a context.xml file is
                // added at a later point
                deployedApp.redeployResources.put(
                        xmlCopy.getAbsolutePath(),
                        Long.valueOf(0));
                if (!xml.exists()) {
                    deployedApp.redeployResources.put(
                            xml.getAbsolutePath(),
                            Long.valueOf(0));
                }
            }
            addWatchedResources(deployedApp, dir.getAbsolutePath(), context);
            // Add the global redeploy resources (which are never deleted) at
            // the end so they don't interfere with the deletion process
            addGlobalRedeployResources(deployedApp);
        }

        deployed.put(cn.getName(), deployedApp);

        if( log.isInfoEnabled() ) {
            log.info(sm.getString("hostConfig.deployDir.finished",
                    dir.getAbsolutePath(), Long.valueOf(System.currentTimeMillis() - startTime)));
        }
    }

LifecycleBase

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StandardContent
  protected void fireLifecycleEvent(String type, Object data) {
        LifecycleEvent event = new LifecycleEvent(this, type, data);
        for (LifecycleListener listener : lifecycleListeners) {
            listener.lifecycleEvent(event);
        }
    }

ContextConfig

lifecycleEvent

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@Override
 public void lifecycleEvent(LifecycleEvent event) {

     // Identify the context we are associated with
     try {
         context = (Context) event.getLifecycle();
     } catch (ClassCastException e) {
         log.error(sm.getString("contextConfig.cce", event.getLifecycle()), e);
         return;
     }

     // Process the event that has occurred
     if (event.getType().equals(Lifecycle.CONFIGURE_START_EVENT)) {
         configureStart();
     } else if (event.getType().equals(Lifecycle.BEFORE_START_EVENT)) {
         beforeStart();
     } else if (event.getType().equals(Lifecycle.AFTER_START_EVENT)) {
         // Restore docBase for management tools
         if (originalDocBase != null) {
             context.setDocBase(originalDocBase);
         }
     } else if (event.getType().equals(Lifecycle.CONFIGURE_STOP_EVENT)) {
         configureStop();
     } else if (event.getType().equals(Lifecycle.AFTER_INIT_EVENT)) {
         init();
     } else if (event.getType().equals(Lifecycle.AFTER_DESTROY_EVENT)) {
         destroy();
     }

 }

configureStart

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/**
   * Process a "contextConfig" event for this Context.
   */
  protected synchronized void configureStart() {
      // Called from StandardContext.start()

      if (log.isDebugEnabled()) {
          log.debug(sm.getString("contextConfig.start"));
      }

      if (log.isDebugEnabled()) {
          log.debug(sm.getString("contextConfig.xmlSettings",
                  context.getName(),
                  Boolean.valueOf(context.getXmlValidation()),
                  Boolean.valueOf(context.getXmlNamespaceAware())));
      }

      webConfig();
      // 为了正常启动
      context.addServletContainerInitializer(new JasperInitializer(),null);
      if (!context.getIgnoreAnnotations()) {
          applicationAnnotationsConfig();
      }
      if (ok) {
          validateSecurityRoles();
      }

      // Configure an authenticator if we need one
      if (ok) {
          authenticatorConfig();
      }

      // Dump the contents of this pipeline if requested
      if (log.isDebugEnabled()) {
          log.debug("Pipeline Configuration:");
          Pipeline pipeline = context.getPipeline();
          Valve valves[] = null;
          if (pipeline != null) {
              valves = pipeline.getValves();
          }
          if (valves != null) {
              for (Valve valve : valves) {
                  log.debug("  " + valve.getClass().getName());
              }
          }
          log.debug("======================");
      }

      // Make our application available if no problems were encountered
      if (ok) {
          context.setConfigured(true);
      } else {
          log.error(sm.getString("contextConfig.unavailable"));
          context.setConfigured(false);
      }

  }

webConfig

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protected void webConfig() {
       /*
        * Anything and everything can override the global and host defaults.
        * This is implemented in two parts
        * - Handle as a web fragment that gets added after everything else so
        *   everything else takes priority
        * - Mark Servlets as overridable so SCI configuration can replace
        *   configuration from the defaults
        */

       /*
        * The rules for annotation scanning are not as clear-cut as one might
        * think. Tomcat implements the following process:
        * - As per SRV.1.6.2, Tomcat will scan for annotations regardless of
        *   which Servlet spec version is declared in web.xml. The EG has
        *   confirmed this is the expected behaviour.
        * - As per http://java.net/jira/browse/SERVLET_SPEC-36, if the main
        *   web.xml is marked as metadata-complete, JARs are still processed
        *   for SCIs.
        * - If metadata-complete=true and an absolute ordering is specified,
        *   JARs excluded from the ordering are also excluded from the SCI
        *   processing.
        * - If an SCI has a @HandlesType annotation then all classes (except
        *   those in JARs excluded from an absolute ordering) need to be
        *   scanned to check if they match.
        */
       WebXmlParser webXmlParser = new WebXmlParser(context.getXmlNamespaceAware(),
               context.getXmlValidation(), context.getXmlBlockExternal());

       Set<WebXml> defaults = new HashSet<>();
       defaults.add(getDefaultWebXmlFragment(webXmlParser));

       WebXml webXml = createWebXml();

       // Parse context level web.xml
       InputSource contextWebXml = getContextWebXmlSource();
       if (!webXmlParser.parseWebXml(contextWebXml, webXml, false)) {
           ok = false;
       }

       ServletContext sContext = context.getServletContext();

       // Ordering is important here

       // Step 1. Identify all the JARs packaged with the application and those
       // provided by the container. If any of the application JARs have a
       // web-fragment.xml it will be parsed at this point. web-fragment.xml
       // files are ignored for container provided JARs.
       Map<String,WebXml> fragments = processJarsForWebFragments(webXml, webXmlParser);

       // Step 2. Order the fragments.
       Set<WebXml> orderedFragments = null;
       orderedFragments =
               WebXml.orderWebFragments(webXml, fragments, sContext);

       // Step 3. Look for ServletContainerInitializer implementations
       if (ok) {
           processServletContainerInitializers();
       }

       if  (!webXml.isMetadataComplete() || typeInitializerMap.size() > 0) {
           // Steps 4 & 5.
           processClasses(webXml, orderedFragments);
       }

       if (!webXml.isMetadataComplete()) {
           // Step 6. Merge web-fragment.xml files into the main web.xml
           // file.
           if (ok) {
               ok = webXml.merge(orderedFragments);
           }

           // Step 7. Apply global defaults
           // Have to merge defaults before JSP conversion since defaults
           // provide JSP servlet definition.
           webXml.merge(defaults);

           // Step 8. Convert explicitly mentioned jsps to servlets
           if (ok) {
               convertJsps(webXml);
           }

           // Step 9. Apply merged web.xml to Context
           if (ok) {
               configureContext(webXml);
           }
       } else {
           webXml.merge(defaults);
           convertJsps(webXml);
           configureContext(webXml);
       }

       if (context.getLogEffectiveWebXml()) {
           log.info("web.xml:\n" + webXml.toXml());
       }

       // Always need to look for static resources
       // Step 10. Look for static resources packaged in JARs
       if (ok) {
           // Spec does not define an order.
           // Use ordered JARs followed by remaining JARs
           Set<WebXml> resourceJars = new LinkedHashSet<>(orderedFragments);
           for (WebXml fragment : fragments.values()) {
               if (!resourceJars.contains(fragment)) {
                   resourceJars.add(fragment);
               }
           }
           processResourceJARs(resourceJars);
           // See also StandardContext.resourcesStart() for
           // WEB-INF/classes/META-INF/resources configuration
       }

       // Step 11. Apply the ServletContainerInitializer config to the
       // context
       if (ok) {
           for (Map.Entry<ServletContainerInitializer,
                   Set<Class<?>>> entry :
                       initializerClassMap.entrySet()) {
               if (entry.getValue().isEmpty()) {
                   context.addServletContainerInitializer(
                           entry.getKey(), null);
               } else {
                   context.addServletContainerInitializer(
                           entry.getKey(), entry.getValue());
               }
           }
       }
   }

getDefaultWebXmlFragment

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private WebXml getDefaultWebXmlFragment(WebXmlParser webXmlParser) {

      // Host should never be null
      Host host = (Host) context.getParent();

      DefaultWebXmlCacheEntry entry = hostWebXmlCache.get(host);

      InputSource globalWebXml = getGlobalWebXmlSource();
      InputSource hostWebXml = getHostWebXmlSource();

      long globalTimeStamp = 0;
      long hostTimeStamp = 0;

      if (globalWebXml != null) {
          URLConnection uc = null;
          try {
              URL url = new URL(globalWebXml.getSystemId());
              uc = url.openConnection();
              globalTimeStamp = uc.getLastModified();
          } catch (IOException e) {
              globalTimeStamp = -1;
          } finally {
              if (uc != null) {
                  try {
                      uc.getInputStream().close();
                  } catch (IOException e) {
                      ExceptionUtils.handleThrowable(e);
                      globalTimeStamp = -1;
                  }
              }
          }
      }

      if (hostWebXml != null) {
          URLConnection uc = null;
          try {
              URL url = new URL(hostWebXml.getSystemId());
              uc = url.openConnection();
              hostTimeStamp = uc.getLastModified();
          } catch (IOException e) {
              hostTimeStamp = -1;
          } finally {
              if (uc != null) {
                  try {
                      uc.getInputStream().close();
                  } catch (IOException e) {
                      ExceptionUtils.handleThrowable(e);
                      hostTimeStamp = -1;
                  }
              }
          }
      }

      if (entry != null && entry.getGlobalTimeStamp() == globalTimeStamp &&
              entry.getHostTimeStamp() == hostTimeStamp) {
          InputSourceUtil.close(globalWebXml);
          InputSourceUtil.close(hostWebXml);
          return entry.getWebXml();
      }

      // Parsing global web.xml is relatively expensive. Use a sync block to
      // make sure it only happens once. Use the pipeline since a lock will
      // already be held on the host by another thread
      synchronized (host.getPipeline()) {
          entry = hostWebXmlCache.get(host);
          if (entry != null && entry.getGlobalTimeStamp() == globalTimeStamp &&
                  entry.getHostTimeStamp() == hostTimeStamp) {
              return entry.getWebXml();
          }

          WebXml webXmlDefaultFragment = createWebXml();
          webXmlDefaultFragment.setOverridable(true);
          // Set to distributable else every app will be prevented from being
          // distributable when the default fragment is merged with the main
          // web.xml
          webXmlDefaultFragment.setDistributable(true);
          // When merging, the default welcome files are only used if the app has
          // not defined any welcomes files.
          webXmlDefaultFragment.setAlwaysAddWelcomeFiles(false);

          // Parse global web.xml if present
          if (globalWebXml == null) {
              // This is unusual enough to log
              log.info(sm.getString("contextConfig.defaultMissing"));
          } else {
              if (!webXmlParser.parseWebXml(
                      globalWebXml, webXmlDefaultFragment, false)) {
                  ok = false;
              }
          }

          // Parse host level web.xml if present
          // Additive apart from welcome pages
          webXmlDefaultFragment.setReplaceWelcomeFiles(true);

          if (!webXmlParser.parseWebXml(
                  hostWebXml, webXmlDefaultFragment, false)) {
              ok = false;
          }

          // Don't update the cache if an error occurs
          if (globalTimeStamp != -1 && hostTimeStamp != -1) {
              entry = new DefaultWebXmlCacheEntry(webXmlDefaultFragment,
                      globalTimeStamp, hostTimeStamp);
              hostWebXmlCache.put(host, entry);
              // Add a Lifecycle listener to the Host that will remove it from
              // the hostWebXmlCache once the Host is destroyed
              host.addLifecycleListener(new HostWebXmlCacheCleaner());
          }

          return webXmlDefaultFragment;
      }
  }

标签解析

server

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  public StandardServer() {

       super();

       globalNamingResources = new NamingResourcesImpl();
       globalNamingResources.setContainer(this);

       if (isUseNaming()) {
           namingContextListener = new NamingContextListener();
           addLifecycleListener(namingContextListener);
       } else {
           namingContextListener = null;
       }

   }

/**
    * Global naming resources context.
    */
   private javax.naming.Context globalNamingContext = null;


   /**
    * Global naming resources.
    */
   private NamingResourcesImpl globalNamingResources = null;


   /**
    * The naming context listener for this web application.
    */
   private final NamingContextListener namingContextListener;


   /**
    * The port number on which we wait for shutdown commands.
    */
   private int port = 8005;

   /**
    * The address on which we wait for shutdown commands.
    */
   private String address = "localhost";


   /**
    * A random number generator that is <strong>only</strong> used if
    * the shutdown command string is longer than 1024 characters.
    */
   private Random random = null;


   /**
   只需要关注这个
    * The set of Services associated with this Server.
    */
   private Service services[] = new Service[0];
   private final Object servicesLock = new Object();


   /**
    * The shutdown command string we are looking for.
    */
   private String shutdown = "SHUTDOWN";


   /**
    * The string manager for this package.
    */
   private static final StringManager sm =
       StringManager.getManager(Constants.Package);


   /**
    * The property change support for this component.
    */
   final PropertyChangeSupport support = new PropertyChangeSupport(this);

   private volatile boolean stopAwait = false;

   private Catalina catalina = null;

   private ClassLoader parentClassLoader = null;

   /**
    * Thread that currently is inside our await() method.
    */
   private volatile Thread awaitThread = null;

   /**
    * Server socket that is used to wait for the shutdown command.
    */
   private volatile ServerSocket awaitSocket = null;

   private File catalinaHome = null;

   private File catalinaBase = null;

   private final Object namingToken = new Object();

ObjectCreateRule

begin

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public void begin(String namespace, String name, Attributes attributes)
           throws Exception {

       // Identify the name of the class to instantiate
    // classname 在初始化ObjectCreateRule对象时就指定好了
       String realClassName = className;
       if (attributeName != null) {
           //这里可以通过server标签指定 Server类
           String value = attributes.getValue(attributeName);
           if (value != null) {
               realClassName = value;
           }
       }
       if (digester.log.isDebugEnabled()) {
           digester.log.debug("[ObjectCreateRule]{" + digester.match +
                   "}New " + realClassName);
       }

       if (realClassName == null) {
           throw new NullPointerException("No class name specified for " +
                   namespace + " " + name);
       }

       // Instantiate the new object and push it on the context stack
       Class<?> clazz = digester.getClassLoader().loadClass(realClassName);
       Object instance = clazz.getConstructor().newInstance();
    //server的实例压栈
       digester.push(instance);
   }

body

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  public void body(String namespace, String name, String text) throws Exception {
        // NO-OP by default.
    }
啥也不干

end

弹出当前对象

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@Override
 public void end(String namespace, String name) throws Exception {

     Object top = digester.pop();
     if (digester.log.isDebugEnabled()) {
         digester.log.debug("[ObjectCreateRule]{" + digester.match +
                 "} Pop " + top.getClass().getName());
     }

 }

SetPropertiesRule

begin

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@Override
 public void begin(String namespace, String theName, Attributes attributes)
         throws Exception {

     // Populate the corresponding properties of the top object
     // 获取栈顶元素，但是不弹出
     Object top = digester.peek();
     if (digester.log.isDebugEnabled()) {
         if (top != null) {
             digester.log.debug("[SetPropertiesRule]{" + digester.match +
                                "} Set " + top.getClass().getName() +
                                " properties");
         } else {
             digester.log.debug("[SetPropertiesRule]{" + digester.match +
                                "} Set NULL properties");
         }
     }

     for (int i = 0; i < attributes.getLength(); i++) {
         String name = attributes.getLocalName(i);
         if ("".equals(name)) {
             name = attributes.getQName(i);
         }
         String value = attributes.getValue(i);

         if (digester.log.isDebugEnabled()) {
             digester.log.debug("[SetPropertiesRule]{" + digester.match +
                     "} Setting property '" + name + "' to '" +
                     value + "'");
         }
         if (!digester.isFakeAttribute(top, name)
             //设置属性，属性设置就是通过setter方法进行设置
                 && !IntrospectionUtils.setProperty(top, name, value)
                 && digester.getRulesValidation()) {
             digester.log.warn("[SetPropertiesRule]{" + digester.match +
                     "} Setting property '" + name + "' to '" +
                     value + "' did not find a matching property.");
         }
     }

 }

body

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public void body(String namespace, String name, String text) throws Exception {
       // NO-OP by default.
   }

end

啥也不干

SetNextRule

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begin啥也不干
    
 bodu啥也不干

end

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@Override
  public void end(String namespace, String name) throws Exception {

      // Identify the objects to be used
      Object child = digester.peek(0);
      Object parent = digester.peek(1);
      if (digester.log.isDebugEnabled()) {
          if (parent == null) {
              digester.log.debug("[SetNextRule]{" + digester.match +
                      "} Call [NULL PARENT]." +
                      methodName + "(" + child + ")");
          } else {
              digester.log.debug("[SetNextRule]{" + digester.match +
                      "} Call " + parent.getClass().getName() + "." +
                      methodName + "(" + child + ")");
          }
      }

      // Call the specified method
      IntrospectionUtils.callMethod1(parent, methodName,
              child, paramType, digester.getClassLoader());

  }

Listener

ObjectCreateRule

与server一样，不过这个对象的class是由标签指定的

SetPropertiesRule

SetNextRule

会给Server设置上监听器

赏

谢谢你请我吃糖果

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tag:

    缺失模块。
    1、请确保node版本大于6.2
    2、在博客根目录（注意不是yilia-plus根目录）执行以下命令：
    npm i hexo-generator-json-content --save

    3、在根目录_config.yml里添加配置： 

      jsonContent:
    meta: false
    pages: false
    posts:
      title: true
      date: true
      path: true
      text: false
      raw: false
      content: false
      slug: false
      updated: false
      comments: false
      link: false
      permalink: false
      excerpt: false
      categories: false
      tags: true

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很惭愧

只做了一点微小的工作
谢谢大家