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 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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package org.apache.catalina;

An Engine is a Container that represents the entire Catalina servlet
engine.  It is useful in the following types of scenarios:

You wish to use Interceptors that see every single request processed
    by the entire engine.
You wish to run Catalina in with a standalone HTTP connector, but still
    want support for multiple virtual hosts.

In general, you would not use an Engine when deploying Catalina connected
to a web server (such as Apache), because the Connector will have
utilized the web server's facilities to determine which Context (or
perhaps even which Wrapper) should be utilized to process this request.

The child containers attached to an Engine are generally implementations
of Host (representing a virtual host) or Context (representing individual
an individual servlet context), depending upon the Engine implementation.

If used, an Engine is always the top level Container in a Catalina
hierarchy. Therefore, the implementation's setParent() method
should throw IllegalArgumentException.
Author:
Craig R. McClanahan/**
 * An <b>Engine</b> is a Container that represents the entire Catalina servlet
 * engine.  It is useful in the following types of scenarios:
 * <ul>
 * <li>You wish to use Interceptors that see every single request processed
 *     by the entire engine.
 * <li>You wish to run Catalina in with a standalone HTTP connector, but still
 *     want support for multiple virtual hosts.
 * </ul>
 * In general, you would not use an Engine when deploying Catalina connected
 * to a web server (such as Apache), because the Connector will have
 * utilized the web server's facilities to determine which Context (or
 * perhaps even which Wrapper) should be utilized to process this request.
 * <p>
 * The child containers attached to an Engine are generally implementations
 * of Host (representing a virtual host) or Context (representing individual
 * an individual servlet context), depending upon the Engine implementation.
 * <p>
 * If used, an Engine is always the top level Container in a Catalina
 * hierarchy. Therefore, the implementation's <code>setParent()</code> method
 * should throw <code>IllegalArgumentException</code>.
 *
 * @author Craig R. McClanahan
 */
public interface Engine extends Container {

    
Returns:
the default host name for this Engine./**
     * @return the default host name for this Engine.
     */
    public String getDefaultHost();


    
Set the default hostname for this Engine.
Params:
defaultHost – The new default host/**
     * Set the default hostname for this Engine.
     *
     * @param defaultHost The new default host
     */
    public void setDefaultHost(String defaultHost);


    
Returns:
the JvmRouteId for this engine./**
     * @return the JvmRouteId for this engine.
     */
    public String getJvmRoute();


    
Set the JvmRouteId for this engine.
Params:
jvmRouteId – the (new) JVM Route ID. Each Engine within a cluster
       must have a unique JVM Route ID./**
     * Set the JvmRouteId for this engine.
     *
     * @param jvmRouteId the (new) JVM Route ID. Each Engine within a cluster
     *        must have a unique JVM Route ID.
     */
    public void setJvmRoute(String jvmRouteId);


    
Returns:
the Service with which we are associated (if any)./**
     * @return the <code>Service</code> with which we are associated (if any).
     */
    public Service getService();


    
Set the Service with which we are associated (if any).
Params:
service – The service that owns this Engine/**
     * 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);
}