Package org.apache.catalina

Interface Wrapper

All Superinterfaces:

Container, Lifecycle

All Known Implementing Classes:

StandardWrapper, Tomcat.ExistingStandardWrapper

public interface Wrapper
extends Container

A Wrapper is a Container that represents an individual servlet definition from the deployment descriptor of the web application. It provides a convenient mechanism to use Interceptors that see every single request to the servlet represented by this definition.

Implementations of Wrapper are responsible for managing the servlet life cycle for their underlying servlet class, including calling init() and destroy() at appropriate times.

The parent Container attached to a Wrapper will generally be an implementation of Context, representing the servlet context (and therefore the web application) within which this servlet executes.

Child Containers are not allowed on Wrapper implementations, so the addChild() method should throw an IllegalArgumentException.

Author:

Craig R. McClanahan

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.catalina.Lifecycle

Lifecycle.SingleUse

Field Summary

Fields

Modifier and Type	Field	Description
static final String	ADD_MAPPING_EVENT	Container event for adding a wrapper.
static final String	REMOVE_MAPPING_EVENT	Container event for removing a wrapper.

Fields inherited from interface org.apache.catalina.Container

ADD_CHILD_EVENT, ADD_VALVE_EVENT, REMOVE_CHILD_EVENT, REMOVE_VALVE_EVENT

Fields inherited from interface org.apache.catalina.Lifecycle

AFTER_DESTROY_EVENT, AFTER_INIT_EVENT, AFTER_START_EVENT, AFTER_STOP_EVENT, BEFORE_DESTROY_EVENT, BEFORE_INIT_EVENT, BEFORE_START_EVENT, BEFORE_STOP_EVENT, CONFIGURE_START_EVENT, CONFIGURE_STOP_EVENT, PERIODIC_EVENT, START_EVENT, STOP_EVENT

Method Summary

Modifier and Type	Method	Description
void	addInitParameter(String name, String value)	Add a new servlet initialization parameter for this servlet.
void	addMapping(String mapping)	Add a mapping associated with the Wrapper.
void	addSecurityReference(String name, String link)	Add a new security role reference record to the set of records for this servlet.
Servlet	allocate()	Allocate an initialized instance of this Servlet that is ready to have its service() method called.
void	deallocate(Servlet servlet)	Decrement the allocation count for the servlet instance.
String	findInitParameter(String name)
String[]	findInitParameters()
String[]	findMappings()
String	findSecurityReference(String name)
String[]	findSecurityReferences()
long	getAvailable()
int	getLoadOnStartup()
MultipartConfigElement	getMultipartConfigElement()
String	getRunAs()
Servlet	getServlet()
String	getServletClass()
String[]	getServletMethods()	Gets the names of the methods supported by the underlying servlet.
void	incrementErrorCount()	Increment the error count value used when monitoring.
boolean	isAsyncSupported()	Does the associated Servlet support async processing?
boolean	isEnabled()	Is the associated Servlet enabled?
boolean	isOverridable()	Is the Servlet overridable by a ServletContainerInitializer?
boolean	isUnavailable()
void	load()	Load and initialize an instance of this Servlet, if there is not already at least one initialized instance.
void	removeInitParameter(String name)	Remove the specified initialization parameter from this Servlet.
void	removeMapping(String mapping)	Remove a mapping associated with the wrapper.
void	removeSecurityReference(String name)	Remove any security role reference for the specified role name.
void	setAsyncSupported(boolean asyncSupport)	Set the async support for the associated Servlet.
void	setAvailable(long available)	Set the available date/time for this servlet, in milliseconds since the epoch.
void	setEnabled(boolean enabled)	Sets the enabled attribute for the associated servlet.
void	setLoadOnStartup(int value)	Set the load-on-startup order value (negative value means load on first call).
void	setMultipartConfigElement(MultipartConfigElement multipartConfig)	Set the multi-part configuration for the associated Servlet.
void	setOverridable(boolean overridable)	Sets the overridable attribute for this Servlet.
void	setRunAs(String runAs)	Set the run-as identity for this servlet.
void	setServlet(Servlet servlet)	Set the associated Servlet instance
void	setServletClass(String servletClass)	Set the fully qualified servlet class name for this servlet.
void	unavailable(UnavailableException unavailable)	Process an UnavailableException, marking this Servlet as unavailable for the specified amount of time.
void	unload()	Unload all initialized instances of this servlet, after calling the destroy() method for each instance.

Methods inherited from interface org.apache.catalina.Container

addChild, addContainerListener, addPropertyChangeListener, backgroundProcess, findChild, findChildren, findContainerListeners, fireContainerEvent, getAccessLog, getBackgroundProcessorDelay, getCatalinaBase, getCatalinaHome, getCluster, getDomain, getLogger, getLogName, getMBeanKeyProperties, getName, getObjectName, getParent, getParentClassLoader, getPipeline, getRealm, getStartStopThreads, logAccess, removeChild, removeContainerListener, removePropertyChangeListener, setBackgroundProcessorDelay, setCluster, setName, setParent, setParentClassLoader, setRealm, setStartStopThreads

Methods inherited from interface org.apache.catalina.Lifecycle

addLifecycleListener, destroy, findLifecycleListeners, getState, getStateName, init, removeLifecycleListener, start, stop

Field Details

ADD_MAPPING_EVENT

static final String ADD_MAPPING_EVENT

Container event for adding a wrapper.

See Also:

• Constant Field Values

REMOVE_MAPPING_EVENT

static final String REMOVE_MAPPING_EVENT

Container event for removing a wrapper.

See Also:

• Constant Field Values

Method Details

getAvailable

long getAvailable()

Returns:

the available date/time for this servlet, in milliseconds since the epoch. If this date/time is in the future, any request for this servlet will return an SC_SERVICE_UNAVAILABLE error. If it is zero, the servlet is currently available. A value equal to Long.MAX_VALUE is considered to mean that unavailability is permanent.

setAvailable

void setAvailable(long available)

Set the available date/time for this servlet, in milliseconds since the epoch. If this date/time is in the future, any request for this servlet will return an SC_SERVICE_UNAVAILABLE error. A value equal to Long.MAX_VALUE is considered to mean that unavailability is permanent.

Parameters:

available - The new available date/time

getLoadOnStartup

int getLoadOnStartup()

Returns:

the load-on-startup order value (negative value means load on first call).

setLoadOnStartup

void setLoadOnStartup(int value)

Set the load-on-startup order value (negative value means load on first call).

Parameters:

value - New load-on-startup value

getRunAs

String getRunAs()

Returns:

the run-as identity for this servlet.

setRunAs

void setRunAs(String runAs)

Set the run-as identity for this servlet.

Parameters:

runAs - New run-as identity value

getServletClass

String getServletClass()

Returns:

the fully qualified servlet class name for this servlet.

setServletClass

void setServletClass(String servletClass)

Set the fully qualified servlet class name for this servlet.

Parameters:

servletClass - Servlet class name

getServletMethods

String[] getServletMethods()
                    throws ServletException

Gets the names of the methods supported by the underlying servlet. This is the same set of methods included in the Allow response header in response to an OPTIONS request method processed by the underlying servlet.

Returns:

Array of names of the methods supported by the underlying servlet

Throws:

ServletException - If the target servlet cannot be loaded

isUnavailable

boolean isUnavailable()

Returns:

true if this Servlet is currently unavailable.

getServlet

Servlet getServlet()

Returns:

the associated Servlet instance.

setServlet

void setServlet(Servlet servlet)

Set the associated Servlet instance

Parameters:

servlet - The associated Servlet

addInitParameter

void addInitParameter(String name,
 String value)

Add a new servlet initialization parameter for this servlet.

Parameters:

name - Name of this initialization parameter to add

value - Value of this initialization parameter to add

addMapping

void addMapping(String mapping)

Add a mapping associated with the Wrapper.

Parameters:

mapping - The new wrapper mapping

addSecurityReference

void addSecurityReference(String name,
 String link)

Add a new security role reference record to the set of records for this servlet.

Parameters:

name - Role name used within this servlet

link - Role name used within the web application

allocate

Servlet allocate()
          throws ServletException

Allocate an initialized instance of this Servlet that is ready to have its service() method called. The previously initialized instance may be returned immediately.

Returns:

a new Servlet instance

Throws:

ServletException - if the Servlet init() method threw an exception

ServletException - if a loading error occurs

deallocate

void deallocate(Servlet servlet)
         throws ServletException

Decrement the allocation count for the servlet instance.

Parameters:

servlet - The servlet to be returned

Throws:

ServletException - if a deallocation error occurs

findInitParameter

String findInitParameter(String name)

Parameters:

name - Name of the requested initialization parameter

Returns:

the value for the specified initialization parameter name, if any; otherwise return null.

findInitParameters

String[] findInitParameters()

Returns:

the names of all defined initialization parameters for this servlet.

findMappings

String[] findMappings()

Returns:

the mappings associated with this wrapper.

findSecurityReference

String findSecurityReference(String name)

Parameters:

name - Security role reference used within this servlet

Returns:

the security role link for the specified security role reference name, if any; otherwise return null.

findSecurityReferences

String[] findSecurityReferences()

Returns:

the set of security role reference names associated with this servlet, if any; otherwise return a zero-length array.

incrementErrorCount

void incrementErrorCount()

Increment the error count value used when monitoring.

load

void load()
   throws ServletException

Load and initialize an instance of this Servlet, if there is not already at least one initialized instance. This can be used, for example, to load Servlets that are marked in the deployment descriptor to be loaded at server startup time.

Throws:

ServletException - if the Servlet init() method threw an exception or if some other loading problem occurs

removeInitParameter

void removeInitParameter(String name)

Remove the specified initialization parameter from this Servlet.

Parameters:

name - Name of the initialization parameter to remove

removeMapping

void removeMapping(String mapping)

Remove a mapping associated with the wrapper.

Parameters:

mapping - The pattern to remove

removeSecurityReference

void removeSecurityReference(String name)

Remove any security role reference for the specified role name.

Parameters:

name - Security role used within this servlet to be removed

unavailable

void unavailable(UnavailableException unavailable)

Process an UnavailableException, marking this Servlet as unavailable for the specified amount of time.

Parameters:

unavailable - The exception that occurred, or null to mark this Servlet as permanently unavailable

unload

void unload()
     throws ServletException

Unload all initialized instances of this servlet, after calling the destroy() method for each instance. This can be used, for example, prior to shutting down the entire servlet engine, or prior to reloading all of the classes from the Loader associated with our Loader's repository.

Throws:

ServletException - if an unload error occurs

getMultipartConfigElement

MultipartConfigElement getMultipartConfigElement()

Returns:

the multi-part configuration for the associated Servlet. If no multi-part configuration has been defined, then null will be returned.

setMultipartConfigElement

void setMultipartConfigElement(MultipartConfigElement multipartConfig)

Set the multi-part configuration for the associated Servlet. To clear the multi-part configuration specify null as the new value.

Parameters:

multipartConfig - The configuration associated with the Servlet

isAsyncSupported

boolean isAsyncSupported()

Does the associated Servlet support async processing? Defaults to false.

Returns:

true if the Servlet supports async

setAsyncSupported

void setAsyncSupported(boolean asyncSupport)

Set the async support for the associated Servlet.

Parameters:

asyncSupport - the new value

isEnabled

boolean isEnabled()

Is the associated Servlet enabled? Defaults to true.

Returns:

true if the Servlet is enabled

setEnabled

void setEnabled(boolean enabled)

Sets the enabled attribute for the associated servlet.

Parameters:

enabled - the new value

isOverridable

boolean isOverridable()

Is the Servlet overridable by a ServletContainerInitializer?

Returns:

true if the Servlet can be overridden in a ServletContainerInitializer

setOverridable

void setOverridable(boolean overridable)

Sets the overridable attribute for this Servlet.

Parameters:

overridable - the new value