/*
* 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 javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.UnavailableException;
/**
* A <b>Wrapper</b> 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.
* <p>
* Implementations of Wrapper are responsible for managing the servlet life
* cycle for their underlying servlet class, including calling init() and
* destroy() at appropriate times, as well as respecting the existence of
* the SingleThreadModel declaration on the servlet class itself.
* <p>
* 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.
* <p>
* Child Containers are not allowed on Wrapper implementations, so the
* <code>addChild()</code> method should throw an
* <code>IllegalArgumentException</code>.
*
* @author Craig R. McClanahan
*
*/
public interface Wrapper extends Container {
// ------------------------------------------------------------- Properties
/**
* Return 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.
*/
public long getAvailable();
/**
* 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.
*
* @param available The new available date/time
*/
public void setAvailable(long available);
/**
* Return the context-relative URI of the JSP file for this servlet.
*/
public String getJspFile();
/**
* Set the context-relative URI of the JSP file for this servlet.
*
* @param jspFile JSP file URI
*/
public void setJspFile(String jspFile);
/**
* Return the load-on-startup order value (negative value means
* load on first call).
*/
public int getLoadOnStartup();
/**
* Set the load-on-startup order value (negative value means
* load on first call).
*
* @param value New load-on-startup value
*/
public void setLoadOnStartup(int value);
/**
* Return the run-as identity for this servlet.
*/
public String getRunAs();
/**
* Set the run-as identity for this servlet.
*
* @param runAs New run-as identity value
*/
public void setRunAs(String runAs);
/**
* Return the fully qualified servlet class name for this servlet.
*/
public String getServletClass();
/**
* Set the fully qualified servlet class name for this servlet.
*
* @param servletClass Servlet class name
*/
public void setServletClass(String servletClass);
/**
* 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.
*
* @return Array of names of the methods supported by the underlying
* servlet
*/
public String[] getServletMethods() throws ServletException;
/**
* Is this servlet currently unavailable?
*/
public boolean isUnavailable();
// --------------------------------------------------------- Public Methods
/**
* Add a new servlet initialization parameter for this servlet.
*
* @param name Name of this initialization parameter to add
* @param value Value of this initialization parameter to add
*/
public void addInitParameter(String name, String value);
/**
* Add a new listener interested in InstanceEvents.
*
* @param listener The new listener
*/
public void addInstanceListener(InstanceListener listener);
/**
* Add a mapping associated with the Wrapper.
*
* @param mapping The new wrapper mapping
*/
public void addMapping(String mapping);
/**
* Add a new security role reference record to the set of records for
* this servlet.
*
* @param name Role name used within this servlet
* @param link Role name used within the web application
*/
public void addSecurityReference(String name, String link);
/**
* Allocate an initialized instance of this Servlet that is ready to have
* its <code>service()</code> method called. If the servlet class does
* not implement <code>SingleThreadModel</code>, the (only) initialized
* instance may be returned immediately. If the servlet class implements
* <code>SingleThreadModel</code>, the Wrapper implementation must ensure
* that this instance is not allocated again until it is deallocated by a
* call to <code>deallocate()</code>.
*
* @exception ServletException if the servlet init() method threw
* an exception
* @exception ServletException if a loading error occurs
*/
public Servlet allocate() throws ServletException;
/**
* Return this previously allocated servlet to the pool of available
* instances. If this servlet class does not implement SingleThreadModel,
* no action is actually required.
*
* @param servlet The servlet to be returned
*
* @exception ServletException if a deallocation error occurs
*/
public void deallocate(Servlet servlet) throws ServletException;
/**
* Return the associated servlet instance.
*/
public Servlet getServlet();
/**
* Return the value for the specified initialization parameter name,
* if any; otherwise return <code>null</code>.
*
* @param name Name of the requested initialization parameter
*/
public String findInitParameter(String name);
/**
* Return the names of all defined initialization parameters for this
* servlet.
*/
public String[] findInitParameters();
/**
* Return the mappings associated with this wrapper.
*/
public String[] findMappings();
/**
* Return the security role link for the specified security role
* reference name, if any; otherwise return <code>null</code>.
*
* @param name Security role reference used within this servlet
*/
public String findSecurityReference(String name);
/**
* Return the set of security role reference names associated with
* this servlet, if any; otherwise return a zero-length array.
*/
public String[] findSecurityReferences();
/**
* Increment the error count value used when monitoring.
*/
public void incrementErrorCount();
/**
* 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.
*
* @exception ServletException if the servlet init() method threw
* an exception
* @exception ServletException if some other loading problem occurs
*/
public void load() throws ServletException;
/**
* Remove the specified initialization parameter from this servlet.
*
* @param name Name of the initialization parameter to remove
*/
public void removeInitParameter(String name);
/**
* Remove a listener no longer interested in InstanceEvents.
*
* @param listener The listener to remove
*/
public void removeInstanceListener(InstanceListener listener);
/**
* Remove a mapping associated with the wrapper.
*
* @param mapping The pattern to remove
*/
public void removeMapping(String mapping);
/**
* Remove any security role reference for the specified role name.
*
* @param name Security role used within this servlet to be removed
*/
public void removeSecurityReference(String name);
/**
* Process an UnavailableException, marking this servlet as unavailable
* for the specified amount of time.
*
* @param unavailable The exception that occurred, or <code>null</code>
* to mark this servlet as permanently unavailable
*/
public void unavailable(UnavailableException unavailable);
/**
* Unload all initialized instances of this servlet, after calling the
* <code>destroy()</code> 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.
*
* @exception ServletException if an unload error occurs
*/
public void unload() throws ServletException;
}