thredds.dqc.server

Class DqcHandler

java.lang.Object

thredds.dqc.server.DqcHandler

Direct Known Subclasses:

JplQuikSCAT, LatestDqcHandler, LatestModel

public abstract class DqcHandler
extends Object

Super-class that each DQC handler must extend.

Only two methods need to be implemented:

• DqcHandler.initWithHandlerConfigDoc( InputStream, InputStream), and
• DqcHandler.handleRequest( HttpServletRequest, HttpServletResponse)

The initWithHandlerConfigDoc() method does not need to do anything. It is just there in case your handler needs some setup information.

Version:

$Id: DqcHandler.java 51 2006-07-12 17:13:13Z caron $

Author:

Ethan Davis

Constructor Summary

Constructors

Constructor and Description
DqcHandler()

Method Summary

Methods

Modifier and Type	Method and Description
static DqcHandler	factory(DqcServletConfigItem handlerInfo, String configPath) Return a DqcHandler using the handler information in the given DqcServletConfigItem.
protected DqcServletConfigItem	getHandlerInfo()
abstract void	handleRequest(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse res) This abstract method is used by the DqcServlet to generate an HttpServletResponse from the given HttpServletRequest.
abstract void	initWithHandlerConfigDoc(URL handlerConfigDocURL) This abstract method initializes the DqcHandler from configuration information.
protected void	setHandlerInfo(DqcServletConfigItem info)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DqcHandler

public DqcHandler()

Method Detail

getHandlerInfo

protected DqcServletConfigItem getHandlerInfo()

setHandlerInfo

protected void setHandlerInfo(DqcServletConfigItem info)

factory

public static final DqcHandler factory(DqcServletConfigItem handlerInfo,
                 String configPath)
                                throws DqcHandlerInstantiationException,
                                       IOException

Return a DqcHandler using the handler information in the given DqcServletConfigItem.

Parameters:

handlerInfo - - the information about the requested DQC handler.

configPath - - the file or resource path to the DqcServlet config files.

Returns:

a DqcHandler as specified in the given DqcServletConfigItem.

Throws:

DqcHandlerInstantiationException - if the requested DqcHandler cannot be instatiated.

IOException - if the config document could not be read.

SecurityException - (runtime)

initWithHandlerConfigDoc

public abstract void initWithHandlerConfigDoc(URL handlerConfigDocURL)
                                       throws IOException

This abstract method initializes the DqcHandler from configuration information. This method must be implemented in your DqcHandler. However, if your handler does not require and config information, this method does not have to do anything (e.g., "{ return; }").

Parameters:

handlerConfigDocURL - - a URL to the DQC handler config document.

Throws:

IOException - if trouble reading config file.

IllegalArgumentException - if config document does not contain the needed information.

handleRequest

public abstract void handleRequest(javax.servlet.http.HttpServletRequest req,
                 javax.servlet.http.HttpServletResponse res)
                            throws IOException,
                                   javax.servlet.ServletException

This abstract method is used by the DqcServlet to generate an HttpServletResponse from the given HttpServletRequest.

Parameters:

req - - HttpServletRequest to a concrete DqcHandler.

res - - HttpServletResponse generated for the given request.

Throws:

IOException - if an I/O error is detected (when communicating with client not for servlet internal IO problems).

javax.servlet.ServletException - if the request could not be handled for some reason.