/*
* 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.core;
import java.util.ArrayList;
import javax.management.ObjectName;
import org.apache.catalina.Contained;
import org.apache.catalina.Container;
import org.apache.catalina.Lifecycle;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.LifecycleState;
import org.apache.catalina.Pipeline;
import org.apache.catalina.Valve;
import org.apache.catalina.util.LifecycleBase;
import org.apache.catalina.valves.ValveBase;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.ExceptionUtils;
/**
* Standard implementation of a processing <b>Pipeline</b> that will invoke
* a series of Valves that have been configured to be called in order. This
* implementation can be used for any type of Container.
*
* <b>IMPLEMENTATION WARNING</b> - This implementation assumes that no
* calls to <code>addValve()</code> or <code>removeValve</code> are allowed
* while a request is currently being processed. Otherwise, the mechanism
* by which per-thread state is maintained will need to be modified.
*
* @author Craig R. McClanahan
*/
public class StandardPipeline extends LifecycleBase
implements Pipeline, Contained {
private static final Log log = LogFactory.getLog(StandardPipeline.class);
// ----------------------------------------------------------- Constructors
/**
* Construct a new StandardPipeline instance with no associated Container.
*/
public StandardPipeline() {
this(null);
}
/**
* Construct a new StandardPipeline instance that is associated with the
* specified Container.
*
* @param container The container we should be associated with
*/
public StandardPipeline(Container container) {
super();
setContainer(container);
}
// ----------------------------------------------------- Instance Variables
/**
* The basic Valve (if any) associated with this Pipeline.
*/
protected Valve basic = null;
/**
* The Container with which this Pipeline is associated.
*/
protected Container container = null;
/**
* Descriptive information about this implementation.
*/
protected static final String info = "org.apache.catalina.core.StandardPipeline/1.0";
/**
* The first valve associated with this Pipeline.
*/
protected Valve first = null;
// --------------------------------------------------------- Public Methods
/**
* Return descriptive information about this implementation class.
*/
public String getInfo() {
return info;
}
@Override
public boolean isAsyncSupported() {
Valve valve = (first!=null)?first:basic;
boolean supported = true;
while (supported && valve!=null) {
supported = supported & valve.isAsyncSupported();
valve = valve.getNext();
}
return supported;
}
// ------------------------------------------------------ Contained Methods
/**
* Return the Container with which this Pipeline is associated.
*/
@Override
public Container getContainer() {
return (this.container);
}
/**
* Set the Container with which this Pipeline is associated.
*
* @param container The new associated container
*/
@Override
public void setContainer(Container container) {
this.container = container;
}
@Override
protected void initInternal() {
// NOOP
}
/**
* Start {@link Valve}s) in this pipeline and implement the requirements
* of {@link LifecycleBase#startInternal()}.
*
* @exception LifecycleException if this component detects a fatal error
* that prevents this component from being used
*/
@Override
protected synchronized void startInternal() throws LifecycleException {
// Start the Valves in our pipeline (including the basic), if any
Valve current = first;
if (current == null) {
current = basic;
}
while (current != null) {
if (current instanceof Lifecycle)
((Lifecycle) current).start();
current = current.getNext();
}
setState(LifecycleState.STARTING);
}
/**
* Stop {@link Valve}s) in this pipeline and implement the requirements
* of {@link LifecycleBase#stopInternal()}.
*
* @exception LifecycleException if this component detects a fatal error
* that prevents this component from being used
*/
@Override
protected synchronized void stopInternal() throws LifecycleException {
setState(LifecycleState.STOPPING);
// Stop the Valves in our pipeline (including the basic), if any
Valve current = first;
if (current == null) {
current = basic;
}
while (current != null) {
if (current instanceof Lifecycle)
((Lifecycle) current).stop();
current = current.getNext();
}
}
@Override
protected void destroyInternal() {
Valve[] valves = getValves();
for (Valve valve : valves) {
removeValve(valve);
}
}
/**
* Return a String representation of this component.
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder("Pipeline[");
sb.append(container);
sb.append(']');
return sb.toString();
}
// ------------------------------------------------------- Pipeline Methods
/**
* <p>Return the Valve instance that has been distinguished as the basic
* Valve for this Pipeline (if any).
*/
@Override
public Valve getBasic() {
return (this.basic);
}
/**
* <p>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 <code>setContainer()</code> will be called, if it
* implements <code>Contained</code>, with the owning Container as an
* argument. The method may throw an <code>IllegalArgumentException</code>
* if this Valve chooses not to be associated with this Container, or
* <code>IllegalStateException</code> if it is already associated with
* a different Container.</p>
*
* @param valve Valve to be distinguished as the basic Valve
*/
@Override
public void setBasic(Valve valve) {
// Change components if necessary
Valve oldBasic = this.basic;
if (oldBasic == valve)
return;
// Stop the old component if necessary
if (oldBasic != null) {
if (getState().isAvailable() && (oldBasic instanceof Lifecycle)) {
try {
((Lifecycle) oldBasic).stop();
} catch (LifecycleException e) {
log.error("StandardPipeline.setBasic: stop", e);
}
}
if (oldBasic instanceof Contained) {
try {
((Contained) oldBasic).setContainer(null);
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
}
}
}
// Start the new component if necessary
if (valve == null)
return;
if (valve instanceof Contained) {
((Contained) valve).setContainer(this.container);
}
if (getState().isAvailable() && valve instanceof Lifecycle) {
try {
((Lifecycle) valve).start();
} catch (LifecycleException e) {
log.error("StandardPipeline.setBasic: start", e);
return;
}
}
// Update the pipeline
Valve current = first;
while (current != null) {
if (current.getNext() == oldBasic) {
current.setNext(valve);
break;
}
current = current.getNext();
}
this.basic = valve;
}
/**
* <p>Add a new Valve to the end of the pipeline associated with this
* Container. Prior to adding the Valve, the Valve's
* <code>setContainer()</code> method will be called, if it implements
* <code>Contained</code>, with the owning Container as an argument.
* The method may throw an
* <code>IllegalArgumentException</code> if this Valve chooses not to
* be associated with this Container, or <code>IllegalStateException</code>
* if it is already associated with a different Container.</p>
*
* @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
*/
@Override
public void addValve(Valve valve) {
// Validate that we can add this Valve
if (valve instanceof Contained)
((Contained) valve).setContainer(this.container);
// Start the new component if necessary
if (getState().isAvailable()) {
if (valve instanceof Lifecycle) {
try {
((Lifecycle) valve).start();
} catch (LifecycleException e) {
log.error("StandardPipeline.addValve: start: ", e);
}
}
}
// Add this Valve to the set associated with this Pipeline
if (first == null) {
first = valve;
valve.setNext(basic);
} else {
Valve current = first;
while (current != null) {
if (current.getNext() == basic) {
current.setNext(valve);
valve.setNext(basic);
break;
}
current = current.getNext();
}
}
container.fireContainerEvent(Container.ADD_VALVE_EVENT, 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.
*/
@Override
public Valve[] getValves() {
ArrayList<Valve> valveList = new ArrayList<Valve>();
Valve current = first;
if (current == null) {
current = basic;
}
while (current != null) {
valveList.add(current);
current = current.getNext();
}
return valveList.toArray(new Valve[0]);
}
public ObjectName[] getValveObjectNames() {
ArrayList<ObjectName> valveList = new ArrayList<ObjectName>();
Valve current = first;
if (current == null) {
current = basic;
}
while (current != null) {
if (current instanceof ValveBase) {
valveList.add(((ValveBase) current).getObjectName());
}
current = current.getNext();
}
return valveList.toArray(new ObjectName[0]);
}
/**
* 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 <code>setContainer(null)</code> method
* will be called if it implements <code>Contained</code>.
*
* @param valve Valve to be removed
*/
@Override
public void removeValve(Valve valve) {
Valve current;
if(first == valve) {
first = first.getNext();
current = null;
} else {
current = first;
}
while (current != null) {
if (current.getNext() == valve) {
current.setNext(valve.getNext());
break;
}
current = current.getNext();
}
if (first == basic) first = null;
if (valve instanceof Contained)
((Contained) valve).setContainer(null);
if (valve instanceof Lifecycle) {
// Stop this valve if necessary
if (getState().isAvailable()) {
try {
((Lifecycle) valve).stop();
} catch (LifecycleException e) {
log.error("StandardPipeline.removeValve: stop: ", e);
}
}
try {
((Lifecycle) valve).destroy();
} catch (LifecycleException e) {
log.error("StandardPipeline.removeValve: destroy: ", e);
}
}
container.fireContainerEvent(Container.REMOVE_VALVE_EVENT, valve);
}
@Override
public Valve getFirst() {
if (first != null) {
return first;
}
return basic;
}
}