org.apache.catalina.Pipeline Maven / Gradle / Ivy
/*
* 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.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.catalina;
import java.util.Set;
/**
* Interface describing a collection of Valves that should be executed
* in sequence when the invoke() method is invoked. It is
* required that a Valve somewhere in the pipeline (usually the last one)
* must process the request and create the corresponding response, rather
* than trying to pass the request on.
*
* There is generally a single Pipeline instance associated with each
* Container. The container's normal request processing functionality is
* generally encapsulated in a container-specific Valve, which should always
* be executed at the end of a pipeline. To facilitate this, the
* setBasic() method is provided to set the Valve instance that
* will always be executed last. Other Valves will be executed in the order
* that they were added, before the basic Valve is executed.
*
* @author Craig R. McClanahan
* @author Peter Donald
*/
public interface Pipeline extends Contained {
/**
* @return the Valve instance that has been distinguished as the basic
* Valve for this Pipeline (if any).
*/
public Valve getBasic();
/**
* Set the Valve instance that has been distinguished as the basic
* Valve for this Pipeline (if any). Prior to setting the basic Valve,
* the Valve's setContainer() will be called, if it
* implements Contained, with the owning Container as an
* argument. The method may throw an IllegalArgumentException
* if this Valve chooses not to be associated with this Container, or
* IllegalStateException if it is already associated with
* a different Container.
*
* @param valve Valve to be distinguished as the basic Valve
*/
public void setBasic(Valve valve);
/**
* Add a new Valve to the end of the pipeline associated with this
* Container. Prior to adding the Valve, the Valve's
* setContainer() method will be called, if it implements
* Contained, with the owning Container as an argument.
* The method may throw an
* IllegalArgumentException if this Valve chooses not to
* be associated with this Container, or IllegalStateException
* if it is already associated with a different Container.
*
* Implementation note: Implementations are expected to trigger the
* {@link Container#ADD_VALVE_EVENT} for the associated container if this
* call is successful.
*
* @param valve Valve to be added
*
* @exception IllegalArgumentException if this Container refused to
* accept the specified Valve
* @exception IllegalArgumentException if the specified Valve refuses to be
* associated with this Container
* @exception IllegalStateException if the specified Valve is already
* associated with a different Container
*/
public void addValve(Valve valve);
/**
* @return the set of Valves in the pipeline associated with this
* Container, including the basic Valve (if any). If there are no
* such Valves, a zero-length array is returned.
*/
public Valve[] getValves();
/**
* Remove the specified Valve from the pipeline associated with this
* Container, if it is found; otherwise, do nothing. If the Valve is
* found and removed, the Valve's setContainer(null) method
* will be called if it implements Contained.
*
* Implementation note: Implementations are expected to trigger the
* {@link Container#REMOVE_VALVE_EVENT} for the associated container if this
* call is successful.
*
* @param valve Valve to be removed
*/
public void removeValve(Valve valve);
/**
* @return the Valve instance that has been distinguished as the basic
* Valve for this Pipeline (if any).
*/
public Valve getFirst();
/**
* Returns true if all the valves in this pipeline support async, false otherwise
* @return true if all the valves in this pipeline support async, false otherwise
*/
public boolean isAsyncSupported();
/**
* Identifies the Valves, if any, in this Pipeline that do not support
* async.
*
* @param result The Set to which the fully qualified class names of each
* Valve in this Pipeline that does not support async will be
* added
*/
public void findNonAsyncValves(Set result);
}