Java tutorial
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For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * * [Additional notices, if required by prior licensing conditions] * */ package org.apache.catalina.core; import javax.management.MBeanServer; import javax.management.MalformedObjectNameException; import javax.management.ObjectName; import org.apache.catalina.Container; import org.apache.catalina.Context; import org.apache.catalina.DefaultContext; import org.apache.catalina.Engine; import org.apache.catalina.Host; import org.apache.catalina.LifecycleException; import org.apache.catalina.Realm; import org.apache.catalina.Service; import org.apache.catalina.realm.JAASRealm; import org.apache.catalina.util.ServerInfo; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.commons.modeler.Registry; import org.apache.commons.modeler.modules.MbeansSource; import java.io.File; import java.util.List; /** * Standard implementation of the <b>Engine</b> interface. Each * child container must be a Host implementation to process the specific * fully qualified host name of that virtual host. * * @author Craig R. McClanahan * @version $Revision: 1.22 $ $Date: 2003/10/21 00:18:25 $ */ public class StandardEngine extends ContainerBase implements Engine { private static Log log = LogFactory.getLog(StandardEngine.class); // ----------------------------------------------------------- Constructors /** * Create a new StandardEngine component with the default basic Valve. */ public StandardEngine() { super(); pipeline.setBasic(new StandardEngineValve()); /* Set the jmvRoute using the system property jvmRoute */ try { setJvmRoute(System.getProperty("jvmRoute")); } catch (Exception ex) { } // By default, the engine will hold the reloading thread backgroundProcessorDelay = 10; } // ----------------------------------------------------- Instance Variables /** * Host name to use when no server host, or an unknown host, * is specified in the request. */ private String defaultHost = null; /** * The descriptive information string for this implementation. */ private static final String info = "org.apache.catalina.core.StandardEngine/1.0"; /** * The <code>Service</code> that owns this Engine, if any. */ private Service service = null; /** Allow the base dir to be specified explicitely for * each engine. In time we should stop using catalina.base property - * otherwise we loose some flexibility. */ private String baseDir = null; /** Optional mbeans config file. This will replace the "hacks" in * jk and ServerListener. The mbeans file will support (transparent) * persistence - soon. It'll probably replace jk2.properties and could * replace server.xml. Of course - the same beans could be loaded and * managed by an external entity - like the embedding app - which * can use a different persistence mechanism. */ private String mbeansFile = null; /** Mbeans loaded by the engine. */ private List mbeans; /** * DefaultContext config */ private DefaultContext defaultContext; /** * The JVM Route ID for this Tomcat instance. All Route ID's must be unique * across the cluster. */ private String jvmRouteId; // ------------------------------------------------------------- Properties /** Provide a default in case no explicit configuration is set * * @return configured realm, or a JAAS realm by default */ public Realm getRealm() { Realm configured = super.getRealm(); // If no set realm has been called - default to JAAS // This can be overriden at engine, context and host level if (configured == null) { configured = new JAASRealm(); this.setRealm(configured); } return configured; } /** * Return the default host. */ public String getDefaultHost() { return (defaultHost); } /** * Set the default host. * * @param host The new default host */ public void setDefaultHost(String host) { String oldDefaultHost = this.defaultHost; if (host == null) { this.defaultHost = null; } else { this.defaultHost = host.toLowerCase(); } support.firePropertyChange("defaultHost", oldDefaultHost, this.defaultHost); } public void setName(String name) { if (domain != null) { // keep name==domain, ignore override // we are already registered super.setName(domain); return; } // The engine name is used as domain domain = name; // XXX should we set it in init() ? It shouldn't matter super.setName(name); } /** * Set the cluster-wide unique identifier for this Engine. * This value is only useful in a load-balancing scenario. * <p> * This property should not be changed once it is set. */ public void setJvmRoute(String routeId) { jvmRouteId = routeId; } /** * Retrieve the cluster-wide unique identifier for this Engine. * This value is only useful in a load-balancing scenario. */ public String getJvmRoute() { return jvmRouteId; } /** * Set the DefaultContext * for new web applications. * * @param defaultContext The new DefaultContext */ public void addDefaultContext(DefaultContext defaultContext) { DefaultContext oldDefaultContext = this.defaultContext; this.defaultContext = defaultContext; support.firePropertyChange("defaultContext", oldDefaultContext, this.defaultContext); } /** * Retrieve the DefaultContext for new web applications. */ public DefaultContext getDefaultContext() { return (this.defaultContext); } /** * Return the <code>Service</code> with which we are associated (if any). */ public Service getService() { return (this.service); } /** * Set the <code>Service</code> with which we are associated (if any). * * @param service The service that owns this Engine */ public void setService(Service service) { this.service = service; } public String getMbeansFile() { return mbeansFile; } public void setMbeansFile(String mbeansFile) { this.mbeansFile = mbeansFile; } public String getBaseDir() { if (baseDir == null) { baseDir = System.getProperty("catalina.base"); } if (baseDir == null) { baseDir = System.getProperty("catalina.home"); } return baseDir; } public void setBaseDir(String baseDir) { this.baseDir = baseDir; } // --------------------------------------------------------- Public Methods /** * Install the StandardContext portion of the DefaultContext * configuration into current Context. * * @param context current web application context */ public void installDefaultContext(Context context) { if (defaultContext != null && defaultContext instanceof StandardDefaultContext) { ((StandardDefaultContext) defaultContext).installDefaultContext(context); } } /** * Import the DefaultContext config into a web application context. * * @param context web application context to import default context */ public void importDefaultContext(Context context) { if (this.defaultContext != null) this.defaultContext.importDefaultContext(context); } /** * Add a child Container, only if the proposed child is an implementation * of Host. * * @param child Child container to be added */ public void addChild(Container child) { if (!(child instanceof Host)) throw new IllegalArgumentException(sm.getString("standardEngine.notHost")); super.addChild(child); } /** * Return descriptive information about this Container implementation and * the corresponding version number, in the format * <code><description>/<version></code>. */ public String getInfo() { return (info); } /** * Disallow any attempt to set a parent for this Container, since an * Engine is supposed to be at the top of the Container hierarchy. * * @param container Proposed parent Container */ public void setParent(Container container) { throw new IllegalArgumentException(sm.getString("standardEngine.notParent")); } private boolean initialized = false; public void init() { if (initialized) return; initialized = true; if (oname == null) { // not registered in JMX yet - standalone mode try { if (domain == null) { domain = getName(); } log.debug("Register " + domain); oname = new ObjectName(domain + ":type=Engine"); controller = oname; Registry.getRegistry().registerComponent(this, oname, null); } catch (Throwable t) { log.info("Error registering ", t); } } if (mbeansFile == null) { String defaultMBeansFile = getBaseDir() + "/conf/tomcat5-mbeans.xml"; File f = new File(defaultMBeansFile); if (f.exists()) mbeansFile = f.getAbsolutePath(); } if (mbeansFile != null) { readEngineMbeans(); } if (mbeans != null) { try { Registry.getRegistry().invoke(mbeans, "init", false); } catch (Exception e) { log.error("Error in init() for " + mbeansFile, e); } } // not needed since the following if statement does the same thing the right way // remove later after checking //if( service==null ) { // try { // ObjectName serviceName=getParentName(); // if( mserver.isRegistered( serviceName )) { // log.info("Registering with the service "); // try { // mserver.invoke( serviceName, "setContainer", // new Object[] { this }, // new String[] { "org.apache.catalina.Container" } ); // } catch( Exception ex ) { // ex.printStackTrace(); // } // } // } catch( Exception ex ) { // log.error("Error registering with service "); // } //} if (service == null) { // for consistency...: we are probably in embeded mode try { service = new StandardService(); service.setContainer(this); service.initialize(); } catch (Throwable t) { t.printStackTrace(); } } } public void destroy() throws LifecycleException { if (!initialized) return; initialized = false; // if we created it, make sure it's also destroyed ((StandardService) service).destroy(); if (mbeans != null) { try { Registry.getRegistry().invoke(mbeans, "destroy", false); } catch (Exception e) { log.error("Error in destroy() for " + mbeansFile, e); } } // if (mbeans != null) { try { for (int i = 0; i < mbeans.size(); i++) { Registry.getRegistry().unregisterComponent((ObjectName) mbeans.get(i)); } } catch (Exception e) { log.error("Error in destroy() for " + mbeansFile, e); } } // force all metadata to be reloaded. // That doesn't affect existing beans. We should make it per // registry - and stop using the static. Registry.getRegistry().resetMetadata(); } /** * Start this Engine component. * * @exception LifecycleException if a startup error occurs */ public void start() throws LifecycleException { if (started) { return; } if (!initialized) { init(); } // Log our server identification information //System.out.println(ServerInfo.getServerInfo()); log.info("Starting Servlet Engine: " + ServerInfo.getServerInfo()); if (mbeans != null) { try { Registry.getRegistry().invoke(mbeans, "start", false); } catch (Exception e) { log.error("Error in start() for " + mbeansFile, e); } } // Standard container startup super.start(); } public void stop() throws LifecycleException { super.stop(); if (mbeans != null) { try { Registry.getRegistry().invoke(mbeans, "stop", false); } catch (Exception e) { log.error("Error in stop() for " + mbeansFile, e); } } } /** * Return a String representation of this component. */ public String toString() { StringBuffer sb = new StringBuffer("StandardEngine["); sb.append(getName()); sb.append("]"); return (sb.toString()); } // ------------------------------------------------------ Protected Methods // -------------------- JMX registration -------------------- public ObjectName preRegister(MBeanServer server, ObjectName name) throws Exception { super.preRegister(server, name); this.setName(name.getDomain()); return name; } // FIXME Remove -- not used public ObjectName getParentName() throws MalformedObjectNameException { if (getService() == null) { return null; } String name = getService().getName(); ObjectName serviceName = new ObjectName(domain + ":type=Service,serviceName=" + name); return serviceName; } public ObjectName createObjectName(String domain, ObjectName parent) throws Exception { if (log.isDebugEnabled()) log.debug("Create ObjectName " + domain + " " + parent); return new ObjectName(domain + ":type=Engine"); } private void readEngineMbeans() { try { MbeansSource mbeansMB = new MbeansSource(); File mbeansF = new File(mbeansFile); mbeansMB.setSource(mbeansF); Registry.getRegistry().registerComponent(mbeansMB, domain + ":type=MbeansFile", null); mbeansMB.load(); mbeansMB.init(); mbeansMB.setRegistry(Registry.getRegistry()); mbeans = mbeansMB.getMBeans(); } catch (Throwable t) { log.error("Error loading " + mbeansFile, t); } } public String getDomain() { if (domain != null) { return domain; } else { return getName(); } } public void setDomain(String domain) { this.domain = domain; } }