org.apache.catalina.core

Class StandardPipeline

Implemented Interfaces:
Contained, Lifecycle, Pipeline

public class StandardPipeline
extends java.lang.Object
implements Pipeline, Contained, Lifecycle

Standard implementation of a processing Pipeline 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. IMPLEMENTATION WARNING - This implementation assumes that no calls to addValve() or removeValve 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

Field Summary

protected Valve
basic
The basic Valve (if any) associated with this Pipeline.
protected Container
container
The Container with which this Pipeline is associated.
protected int
debug
The debugging detail level for this component.
protected String
info
Descriptive information about this implementation.
protected LifecycleSupport
lifecycle
The lifecycle event support for this component.
protected static StringManager
sm
The string manager for this package.
protected boolean
started
Has this component been started yet?
protected Valve[]
valves
The set of Valves (not including the Basic one, if any) associated with this Pipeline.

Fields inherited from interface org.apache.catalina.Lifecycle

AFTER_START_EVENT, AFTER_STOP_EVENT, BEFORE_START_EVENT, BEFORE_STOP_EVENT, START_EVENT, STOP_EVENT

Constructor Summary

StandardPipeline()
Construct a new StandardPipeline instance with no associated Container.
StandardPipeline(Container container)
Construct a new StandardPipeline instance that is associated with the specified Container.

Method Summary

void
addLifecycleListener(LifecycleListener listener)
Add a lifecycle event listener to this component.
void
addValve(Valve valve)
Add a new Valve to the end of the pipeline associated with this Container.
LifecycleListener[]
findLifecycleListeners()
Get the lifecycle listeners associated with this lifecycle.
Valve
getBasic()
Return the Valve instance that has been distinguished as the basic Valve for this Pipeline (if any).
Container
getContainer()
Return the Container with which this Pipeline is associated.
String
getInfo()
Return descriptive information about this implementation class.
ObjectName[]
getValveObjectNames()
Valve[]
getValves()
Return the set of Valves in the pipeline associated with this Container, including the basic Valve (if any).
void
invoke(Request request, Response response)
Cause the specified request and response to be processed by the Valves associated with this pipeline, until one of these valves causes the response to be created and returned.
protected void
log(String message)
Log a message on the Logger associated with our Container (if any).
protected void
log(String message, Throwable throwable)
Log a message on the Logger associated with our Container (if any).
void
removeLifecycleListener(LifecycleListener listener)
Remove a lifecycle event listener from this component.
void
removeValve(Valve valve)
Remove the specified Valve from the pipeline associated with this Container, if it is found; otherwise, do nothing.
void
setBasic(Valve valve)
Set the Valve instance that has been distinguished as the basic Valve for this Pipeline (if any).
void
setContainer(Container container)
Set the Container with which this Pipeline is associated.
void
start()
Prepare for active use of the public methods of this Component.
void
stop()
Gracefully shut down active use of the public methods of this Component.

Field Details

basic

protected Valve basic
The basic Valve (if any) associated with this Pipeline.


container

protected Container container
The Container with which this Pipeline is associated.


debug

protected int debug
The debugging detail level for this component.


info

protected String info
Descriptive information about this implementation.


lifecycle

protected LifecycleSupport lifecycle
The lifecycle event support for this component.


sm

protected static StringManager sm
The string manager for this package.


started

protected boolean started
Has this component been started yet?


valves

protected Valve[] valves
The set of Valves (not including the Basic one, if any) associated with this Pipeline.

Constructor Details

StandardPipeline

public StandardPipeline()
Construct a new StandardPipeline instance with no associated Container.


StandardPipeline

public StandardPipeline(Container container)
Construct a new StandardPipeline instance that is associated with the specified Container.

Parameters:
container - The container we should be associated with

Method Details

addLifecycleListener

public void addLifecycleListener(LifecycleListener listener)
Add a lifecycle event listener to this component.
Specified by:
addLifecycleListener in interface Lifecycle

Parameters:
listener - The listener to add


addValve

public void addValve(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.
Specified by:
addValve in interface Pipeline

Parameters:
valve - Valve to be added


findLifecycleListeners

public LifecycleListener[] findLifecycleListeners()
Get the lifecycle listeners associated with this lifecycle. If this Lifecycle has no listeners registered, a zero-length array is returned.
Specified by:
findLifecycleListeners in interface Lifecycle


getBasic

public Valve getBasic()
Return the Valve instance that has been distinguished as the basic Valve for this Pipeline (if any).
Specified by:
getBasic in interface Pipeline


getContainer

public Container getContainer()
Return the Container with which this Pipeline is associated.
Specified by:
getContainer in interface Contained


getInfo

public String getInfo()
Return descriptive information about this implementation class.


getValveObjectNames

public ObjectName[] getValveObjectNames()


getValves

public Valve[] getValves()
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.
Specified by:
getValves in interface Pipeline


invoke

public void invoke(Request request,
                   Response response)
            throws IOException,
                   ServletException
Cause the specified request and response to be processed by the Valves associated with this pipeline, until one of these valves causes the response to be created and returned. The implementation must ensure that multiple simultaneous requests (on different threads) can be processed through the same Pipeline without interfering with each other's control flow.
Specified by:
invoke in interface Pipeline

Parameters:
request - The servlet request we are processing
response - The servlet response we are creating


log

protected void log(String message)
Log a message on the Logger associated with our Container (if any).

Parameters:
message - Message to be logged


log

protected void log(String message,
                   Throwable throwable)
Log a message on the Logger associated with our Container (if any).

Parameters:
message - Message to be logged
throwable - Associated exception


removeLifecycleListener

public void removeLifecycleListener(LifecycleListener listener)
Remove a lifecycle event listener from this component.
Specified by:
removeLifecycleListener in interface Lifecycle

Parameters:
listener - The listener to remove


removeValve

public void removeValve(Valve valve)
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.
Specified by:
removeValve in interface Pipeline

Parameters:
valve - Valve to be removed


setBasic

public void setBasic(Valve valve)
Set the Valve instance that has been distinguished as the basic Valve for this Pipeline (if any). Prioer 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.
Specified by:
setBasic in interface Pipeline

Parameters:
valve - Valve to be distinguished as the basic Valve


setContainer

public void setContainer(Container container)
Set the Container with which this Pipeline is associated.
Specified by:
setContainer in interface Contained

Parameters:
container - The new associated container


start

public void start()
            throws LifecycleException
Prepare for active use of the public methods of this Component.
Specified by:
start in interface Lifecycle

Throws:
LifecycleException - if this component detects a fatal error that prevents it from being started


stop

public void stop()
            throws LifecycleException
Gracefully shut down active use of the public methods of this Component.
Specified by:
stop in interface Lifecycle

Throws:
LifecycleException - if this component detects a fatal error that needs to be reported


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