com.jcorporate.expresso.core.servlet
Class DBServlet

java.lang.Object
  javax.servlet.GenericServlet
      javax.servlet.http.HttpServlet
          com.jcorporate.expresso.core.servlet.StdServlet
              com.jcorporate.expresso.core.servlet.DBServlet

All Implemented Interfaces:

Serializable, Servlet, ServletConfig

Direct Known Subclasses:

DBCreate, InitServlet, PathHandler, Test, ViewHandler

public abstract class DBServlet

extends StdServlet

A Servlet set up to have access to a relational database from the server side. This is a base class for all database maintenance and reporting servlets

Author:

Michael Nash

See Also:

Serialized Form

Field Summary

protected static String

thisClass

Fields inherited from class com.jcorporate.expresso.core.servlet.StdServlet

mySchema

Constructor Summary

DBServlet()

Method Summary

void	destroy() Implemented for when the context is unloaded.
void	doGet(HttpServletRequest request, HttpServletResponse response) Ancestor calls this function (with super.doGet) to handle making database connection, getting user login info and other common tasks
void	doPost(HttpServletRequest req, HttpServletResponse res) Ancestor calls this method via super.doPost to handle standard operations
protected String	getDBName(HttpServletRequest request) Return the "alternate" database name, if one is set.
void	init(ServletConfig sc) Standard Servlet init() function
boolean	requireLogin(HttpServletRequest req, HttpServletResponse res, String nextURL) Deprecated. does nothing but return false;
protected void	setDBName(String newDBName, HttpServletRequest req) Set the "alternate" database name
void	setSkipLogin(boolean newSkip)
void	setupChannels(HttpServletRequest req) Set up the logging channels for all DBServlets

Methods inherited from class com.jcorporate.expresso.core.servlet.StdServlet

getSchema, getServerName, getServerPort, getServletPrefix, getServletPrefix, getString, getString, getTitle, handleParam, setSchema, showError, showError

Methods inherited from class javax.servlet.http.HttpServlet

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

Methods inherited from class javax.servlet.GenericServlet

getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class java.lang.Object

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

Field Detail

thisClass

protected static final String thisClass

Constructor Detail

DBServlet

public DBServlet()

Method Detail

init

public void init(ServletConfig sc)
          throws ServletException

Standard Servlet init() function

Specified by:

init in interface Servlet

Overrides:

init in class StdServlet

Parameters:

sc - The servlet Configuration passed by the web.xml file

Throws:

ServletException

destroy

public void destroy()

Implemented for when the context is unloaded.

Specified by:

destroy in interface Servlet

Overrides:

destroy in class StdServlet

doGet

public void doGet(HttpServletRequest request,
                  HttpServletResponse response)
           throws ServletException,
                  IOException

Ancestor calls this function (with super.doGet) to handle making database connection, getting user login info and other common tasks

Overrides:

doGet in class StdServlet

Parameters:

request - Standard request object

response - Standard response object

Throws:

ServletException - If an uncaught exception occurs

IOException - If an I/O error communicating with the client occurs

doPost

public void doPost(HttpServletRequest req,
                   HttpServletResponse res)
            throws ServletException,
                   IOException

Ancestor calls this method via super.doPost to handle standard operations

Overrides:

doPost in class StdServlet

Parameters:

req - Standard request object

res - Standard response object

Throws:

ServletException - If an uncaught exception occurs

IOException - If an I/O error occurs communicating with the client

getDBName

protected String getDBName(HttpServletRequest request)

Return the "alternate" database name, if one is set. Else return an empty string

Parameters:

request - The servlet request

Returns:

The name of the specified alternate database

requireLogin

public boolean requireLogin(HttpServletRequest req,
                            HttpServletResponse res,
                            String nextURL)
                     throws IOException,
                            ServletException,
                            DBException,
                            LogException,
                            HtmlException

Deprecated. does nothing but return false;

Verify that the current user is logged in. If not, try to log in via the stored cookie. If that's not possible, log in as Anonymous

Parameters:

req - Standard request object

res - Standard response object

nextURL - to proceed with when login completed successfully

Returns:

true if login is required

Throws:

IOException - If an I/O error occurs communicating with the client

ServletException - If an uncaught exception occurs

DBException - If a problem occurs accessing login information in the database

LogException

HtmlException

setDBName

protected void setDBName(String newDBName,
                         HttpServletRequest req)
                  throws ServletException

Set the "alternate" database name

Parameters:

newDBName - The new data context to set the session for

req - the servlet request object

Throws:

ServletException

setSkipLogin

public void setSkipLogin(boolean newSkip)

Parameters:

newSkip - set to true if you want login processing skipped

setupChannels

public void setupChannels(HttpServletRequest req)
                   throws ServletException

Set up the logging channels for all DBServlets

Parameters:

req - The servlet request object

Throws:

ServletException