zeta
Class ZetaServlet

java.lang.Object
  |
  +--javax.servlet.GenericServlet
        |
        +--javax.servlet.http.HttpServlet
              |
              +--zeta.ZetaServlet

All Implemented Interfaces:

java.io.Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public class ZetaServlet

extends javax.servlet.http.HttpServlet

Creates an HTTP servlet that dispatches HTTP GET and HTTP POST requests on the ZetaGrid site to specified handlers.

See Also:

Serialized Form

Field Summary

private ConnectionDriver	connectionDriver
private java.io.Writer	errorLog
private java.lang.String	errorLogFilename
private java.util.List	getHandlers Map to handle HTTP GET requests.
private int	id ID for logging.
private java.text.SimpleDateFormat	logFormat
private static int	MAX_BACKUP_INDEX
private static long	MAX_LOG_FILESIZE
private boolean	normalLogging
private int	numberOfStatisticHandlers Number of handlers which handle HTTP GET requests for statistics.
private java.util.Hashtable	parameters
private int	poolsize
private java.util.List	postHandlers Map to handle HTTP POST requests.
private int	serverId ID of the server.
private java.io.Writer	stdLog
private java.lang.String	stdLogFilename

Fields inherited from class javax.servlet.http.HttpServlet

Fields inherited from class javax.servlet.GenericServlet

Constructor Summary

ZetaServlet()
Initialize lists to handle HTTP GET and HTTP POST requests.

Method Summary

void	addStatisticHandler(java.lang.String name, java.lang.String parameter, java.util.List statisticHandlers) Adds a statistic handler.
void	destroy() Destroy the resources that are held for the life of the servlet.
protected void	doGet(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp) Called by the server to allow this servlet to handle a GET request.
protected void	doPost(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp) Called by the server to allow this servlet to handle a POST request.
private java.lang.Object	findHandler(java.util.List handlers, java.lang.String name) Searches the handler by the specified name.
java.sql.Connection	getConnection() Returns a connection to the back-end database.
java.lang.String	getHandlerAddress(java.lang.Class handler) Searches the handler address by the specified class of this GET handler.
java.lang.String	getInitParameter(java.lang.String name)
int	getInitParameter(java.lang.String name, int defaultValue)
java.util.Enumeration	getInitParameterNames()
private java.lang.Object	getInstance(java.lang.Class handlerClass) Builds a new instance of the specified handler class
int	getNumberOfStatisticHandlers() Returns the number of defined statistic handlers.
int	getServerId() Returns the ID of the server.
AbstractHandler	getStatisticHandler(java.lang.Class handler) Searches the handler object by the specified class of this statistic handler.
java.lang.Class	getStatisticHandlerClass(int i) Returns the i-th defined statistic handler.
java.lang.String	getStatisticHandlerName(java.lang.Class handler) Searches the handler name by the specified class of this statistic handler.
boolean	hasSeparateFiles()
void	init() Initialize the resources that are held for the life of the servlet.
private void	initLogFile()
void	log(java.lang.String msg)
void	log(java.lang.Throwable t)
private void	rollOver(java.lang.String filename, int maxBackupIndex) Implements the usual roll over behaviour of log files.
void	setServerId(int serverId) Sets the ID of the server.

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doOptions, doPut, doTrace, getLastModified, service, service

Methods inherited from class javax.servlet.GenericServlet

getServletConfig, getServletContext, getServletInfo, getServletName, init, log

Methods inherited from class java.lang.Object

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

Field Detail

parameters

private java.util.Hashtable parameters

getHandlers

private java.util.List getHandlers

Map to handle HTTP GET requests.

postHandlers

private java.util.List postHandlers

Map to handle HTTP POST requests.

numberOfStatisticHandlers

private int numberOfStatisticHandlers

Number of handlers which handle HTTP GET requests for statistics.

serverId

private int serverId

ID of the server.

id

private int id

ID for logging.

poolsize

private int poolsize

connectionDriver

private ConnectionDriver connectionDriver

stdLogFilename

private java.lang.String stdLogFilename

stdLog

private java.io.Writer stdLog

errorLogFilename

private java.lang.String errorLogFilename

errorLog

private java.io.Writer errorLog

logFormat

private java.text.SimpleDateFormat logFormat

normalLogging

private boolean normalLogging

MAX_LOG_FILESIZE

private static final long MAX_LOG_FILESIZE

See Also:

Constant Field Values

MAX_BACKUP_INDEX

private static final int MAX_BACKUP_INDEX

See Also:

Constant Field Values

Constructor Detail

ZetaServlet

public ZetaServlet()

Initialize lists to handle HTTP GET and HTTP POST requests.

Method Detail

getInitParameter

public java.lang.String getInitParameter(java.lang.String name)

Specified by:

getInitParameter in interface javax.servlet.ServletConfig

Overrides:

getInitParameter in class javax.servlet.GenericServlet

getInitParameterNames

public java.util.Enumeration getInitParameterNames()

Specified by:

getInitParameterNames in interface javax.servlet.ServletConfig

Overrides:

getInitParameterNames in class javax.servlet.GenericServlet

getInitParameter

public int getInitParameter(java.lang.String name,
                            int defaultValue)

hasSeparateFiles

public boolean hasSeparateFiles()

init

public void init()
          throws javax.servlet.ServletException

Initialize the resources that are held for the life of the servlet. Setup the database connection driver and the configured handlers for HTTP GET and HTTP POST requests.

Overrides:

init in class javax.servlet.GenericServlet

javax.servlet.ServletException

destroy

public void destroy()

Destroy the resources that are held for the life of the servlet.

Specified by:

destroy in interface javax.servlet.Servlet

Overrides:

destroy in class javax.servlet.GenericServlet

getConnection

public java.sql.Connection getConnection()
                                  throws javax.servlet.ServletException

Returns a connection to the back-end database. This connection must be closed.

Returns:

a connection to the back-end database.

javax.servlet.ServletException

getServerId

public int getServerId()

Returns the ID of the server.

Returns:

the ID of the server.

setServerId

public void setServerId(int serverId)

Sets the ID of the server.

getNumberOfStatisticHandlers

public int getNumberOfStatisticHandlers()

Returns the number of defined statistic handlers.

Returns:

the number of defined statistic handlers.

getStatisticHandlerClass

public java.lang.Class getStatisticHandlerClass(int i)

Returns the i-th defined statistic handler.

Parameters:

i - index

Returns:

the i-th defined statistic handler.

getStatisticHandlerName

public java.lang.String getStatisticHandlerName(java.lang.Class handler)

Searches the handler name by the specified class of this statistic handler.

Parameters:

handler - class of a statistic handler

Returns:

name of the handler; null if no handler is found.

getStatisticHandler

public AbstractHandler getStatisticHandler(java.lang.Class handler)

Searches the handler object by the specified class of this statistic handler.

Parameters:

handler - class of a statistic handler

Returns:

object of the handler; null if no handler is found.

getHandlerAddress

public java.lang.String getHandlerAddress(java.lang.Class handler)

Searches the handler address by the specified class of this GET handler.

Parameters:

handler - class of a statistic handler

Returns:

HTTP address of the handler; null if no handler is found.

doGet

protected void doGet(javax.servlet.http.HttpServletRequest req,
                     javax.servlet.http.HttpServletResponse resp)
              throws javax.servlet.ServletException,
                     java.io.IOException

Called by the server to allow this servlet to handle a GET request.

Overrides:

doGet in class javax.servlet.http.HttpServlet

Parameters:

req - contains the request the client has made of the servlet.

resp - contains the response the servlet sends to the client.

Throws:

java.io.IOException - if an I/O error occurs when the servlet handles the GET request.

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

See Also:

HttpServlet.doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)

doPost

protected void doPost(javax.servlet.http.HttpServletRequest req,
                      javax.servlet.http.HttpServletResponse resp)
               throws javax.servlet.ServletException,
                      java.io.IOException

Called by the server to allow this servlet to handle a POST request.

Overrides:

doPost in class javax.servlet.http.HttpServlet

Parameters:

req - contains the request the client has made of the servlet.

resp - contains the response the servlet sends to the client.

Throws:

java.io.IOException - if an I/O error occurs when the servlet handles the POST request.

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

See Also:

HttpServlet.doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)

addStatisticHandler

public void addStatisticHandler(java.lang.String name,
                                java.lang.String parameter,
                                java.util.List statisticHandlers)
                         throws java.lang.Exception

Adds a statistic handler.

java.lang.Exception

log

public void log(java.lang.String msg)

Overrides:

log in class javax.servlet.GenericServlet

log

public void log(java.lang.Throwable t)

initLogFile

private void initLogFile()

rollOver

private void rollOver(java.lang.String filename,
                      int maxBackupIndex)

Implements the usual roll over behaviour of log files.

findHandler

private java.lang.Object findHandler(java.util.List handlers,
                                     java.lang.String name)

Searches the handler by the specified name.

Parameters:

handlers - container with the handler

name - name of the handler which is searched

Returns:

instance of the handler which name starts with the specified name; null if no handler is found.

getInstance

private java.lang.Object getInstance(java.lang.Class handlerClass)
                              throws java.lang.Exception,
                                     java.lang.Error

Builds a new instance of the specified handler class

Parameters:

handlerClass - class of the handler

java.lang.Exception

java.lang.Error