Web Development with Java

private
Method methodDefault = 
null
;
protected
HttpServletRequest request;
protected
HttpServletResponse response;
protected
Logger logger;
public
HelperBaseCh4(HttpServletRequest request,
HttpServletResponse response) {
this
.request = request;
this
.response = response;
logger = Logger.getLogger(“bytesizebook.webdev”);
logger.setLevel(Level.DEBUG);
}
protected void
doGet()
throws
ServletException, IOException {
response.getWriter()
.print(“The doGet method must be overridden” +
“ in the 
class
that 
extends
HelperBase.”);
}
protected void
doPost()
throws
ServletException, IOException {
response.getWriter()
.print(“The doPost method must be overridden” +
“ in the 
class
that 
extends
HelperBase.”);
}
protected abstract void
copyFromSession(Object helper);
public void
addHelperToSession(String name, 
SessionData state) {
if
(SessionData.READ == state) {
Object sessionObj = 
request.getSession().getAttribute(name);
if
(sessionObj != 
null
) {
copyFromSession(sessionObj);
}
}
request.getSession().setAttribute(name, 
this
);
}
public void
addHelperToSession(String name, 
boolean
checkSession) {
if
(checkSession) {
Object sessionObj = 
request.getSession().getAttribute(name);
if
(sessionObj != 
null
) {
copyFromSession(sessionObj);
}
}
request.getSession().setAttribute(name, 
this
);
}

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Appendix