uk.co.weft.htform
Class Page

java.lang.Object
  javax.servlet.GenericServlet
      javax.servlet.http.HttpServlet
          uk.co.weft.maybeupload.MaybeUploadServlet
              uk.co.weft.htform.Servlet
                  uk.co.weft.htform.WithExceptionHandlerServlet
                      uk.co.weft.htform.Page

All Implemented Interfaces:

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

Direct Known Subclasses:

CompositeStylesheetSample, Form

public abstract class Page

extends WithExceptionHandlerServlet

An HTML page, generated by a servlet. This class (and consequently all servlets which are subclasses of this class) know about the following configuration parameters, in addition to those handled by Servlet:

doctype

String: The SGML doctypt to declare for this page. Optional. Defaults to HTML 4 Transitional.

dynamic_foot_include

Boolean: whether or not the foot_include_url should be pulled at each service. May be used in conjunction with specialisation of getHeadIncludeURL, in which case the URL pulled may be computed from the context. Optional. Defaults to false. Since Jacquard 1.9.

dynamic_head_include

Boolean: whether or not the head_include_url should be pulled at each service. May be used in conjunction with specialisation of getHeadIncludeURL, in which case the URL pulled may be computed from the context. Optional. Defaults to false.

foot_include_url

URL: a URL pointing to an HTML fragment to be spliced in to the end of the BODY of the page - you must include a valid URL here. If you're using dynamic head includes and specialising getHeadIncludeURL() you may not actually use the URL you supply here but you must nevertheless supply a valid one. Optional. No default. Since Jacquard 1.9.

head_include_url

URL: a URL pointing to an HTML fragment to be spliced in to the start of the BODY of the page - you must include a valid URL here. If you're using dynamic head includes and specialising getHeadIncludeURL() you may not actually use the URL you supply here but you must nevertheless supply a valid one. Optional. No default.

image_url_base

URL (may be relative): the URL of a directory from which utility images can be fetched. Optional. Defaults to ../images/

print_stylesheet

URL (may be relative): The URL of the CSS stylesheet to use for media="print". Optional. No default.

stylesheet

URL (may be relative): The URL of the CSS stylesheet to be used to format this page. Optional.

title

String: The title of this page. Optional. No default.

Version:

$Revision: 1.47.4.4 $ This revision: $Author: simon $

Author:

Simon Brooke

See Also:

Servlet, Serialized Form

Field Summary

static java.lang.String	DOCTYPECONFIGTOKEN a magic token on which we will seek the value of the document type declaration in the configuration
protected java.lang.Boolean	dynamicFootInclude whether the fragment should be refetched at each request (we really don't want to have to do this
protected java.lang.Boolean	dynamicHeadInclude whether the fragment should be refetched at each request (we really don't want to have to do this
protected java.lang.String	footInclude an HTML fragment to include at the beginning of the body of each page
protected java.lang.String	footIncludeURL the URL from which that fragment should be fetched
protected java.lang.String	headInclude an HTML fragment to include at the beginning of the body of each page
protected java.lang.String	headIncludeURL the URL from which that fragment should be fetched
protected java.lang.String	imageUrlBase the base URL for utility images I may need
protected Layout	layout My layout engine.
protected java.lang.String	printStylesheet The URL of my print stylsheet
static java.lang.String	PRINTSTYLESHEETCONFIGTOKEN a magic token on which we will seek in the configuration for the URL of the stylesheet for media="print"
protected java.lang.String	stylesheet The URI of my stylesheet
static java.lang.String	STYLESHEETCONFIGTOKEN a magic token on which we will seek in the configuration for the URL of the stylesheet for media="screen"
protected java.lang.String	title my title.
protected java.lang.String	titleMagicToken Deprecated. use TITLEMAGICTOKEN
static java.lang.String	TITLEMAGICTOKEN a magic token to allow my title to be extracted from the context

Fields inherited from class uk.co.weft.htform.WithExceptionHandlerServlet

EXCEPTIONHANDLERCLASSCONFIGTOKEN

Fields inherited from class uk.co.weft.htform.Servlet

calendar, conf, contentType, CONTENTTYPECONFIGTOKEN, cookieDomain, cookiePath, COOKIESCONFIGTOKEN, cookieTTL, dbPassword, dbUrl, dbUsername, debug, DEBUGCONFIGTOKEN, driverName, embedded, here, identity, localeMagicToken, LOCALEMAGICTOKEN, outputStreamMagicToken, OUTPUTSTREAMMAGICTOKEN, parsePathInfo, PATHINFOMAGICTOKEN, ready, redirectMagicToken, REDIRECTMAGICTOKEN, requestMagicToken, REQUESTMAGICTOKEN, resourceBundleName, responseMagicToken, RESPONSEMAGICTOKEN, servletMagicToken, SERVLETMAGICTOKEN, sessionMagicToken, SESSIONMAGICTOKEN, USEHTTPSCONFIGTOKEN, zone

Fields inherited from class uk.co.weft.maybeupload.MaybeUploadServlet

allowOverwrite, maxUpload, saveUploadedFilesToDisk, silentlyRename, uploadDir, uploadDirPath, uploadDirURL

Fields inherited from interface uk.co.weft.htform.ResourceConsumer

RESOURCEBUNDLEMAGICTOKEN

Constructor Summary

Page()

Method Summary

protected abstract void	doBody(Context context) Specialise! Do not use! Output what is to appear on your page between (but not including) the BODY tags.
protected void	doFoot(Context context) Output standardised footer.
protected void	doFoot(Context context, java.lang.String message) output a footer onto my output stream, incorporating a supplied message.
protected void	doHead(Context context) Output an HTML HEAD section, up to but not including the closing /HEAD tag.
protected void	doHeadBodySep(Context context) Output the close of the head tag and the opening of the body tag.
protected void	generateContent(Context context) Generate the content of a normal page, by generating first the head, then the body tag, then the body content.
protected java.lang.String	getFootInclude(Context context) fetch the foot include (if any) for this context.
protected java.net.URL	getFootIncludeURL(java.lang.String dflt, Context context) If you're using dynamic foot includes, you probably want to specialise to generate a URL based on something in the context.
protected java.net.URL	getFootIncludeURL(java.net.URL dflt, Context context) If you're using dynamic foot includes, you probably want to specialise to generate a URL based on something in the context.
protected java.lang.String	getHeadInclude(Context context) fetch the head include (if any) for this context.
protected java.net.URL	getHeadIncludeURL(java.lang.String dflt, Context context) If you're using dynamic head includes, you probably want to specialise to generate a URL based on something in the context.
protected java.net.URL	getHeadIncludeURL(java.net.URL dflt, Context context) Deprecated. replaced with getHeadIncludeURL(String,Context) which is able to fix up relative URLs
Layout	getLayout(Context context) Return my layout engine for this context.
protected java.lang.String	getStylesheet(Context context) Deprecated. probably better to use getStylesheets(Context)
java.util.Vector	getStylesheets(Context context) get the URLs of multiple stylesheets to use in this context.
protected boolean	getTables() return the value of my tables iv
protected java.lang.String	getTitle() Deprecated. use getTitle( Context) in preference
protected java.lang.String	getTitle(Context context) construct and return a suitable title for this page in this context.
void	init(Context config) Initialisation: Set up my variables from my configuration.
protected void	outputRedirectBlock(Context context) Output a stub HTML page with a 'refresh' meta.
protected java.lang.String	readStringFromURL(java.net.URL source) read the value at this URL and return it as a string

Methods inherited from class uk.co.weft.htform.WithExceptionHandlerServlet

whinge, whinge, whinge

Methods inherited from class uk.co.weft.htform.Servlet

addCookie, addCookie, coerceCookiesToContext, coerceToContext, coerceToContext, coerceToContext, coerceToContext, coerceToUrl, createContext, doGet, doPost, fixupMagicValues, getCalendar, getContentType, getDebug, getLocale, getOutputStream, getResource, getResourceString, getServletInfo, grs, grs, handleAction, handleCookies, handleRedirect, init, makeReady, setCookieValues, storeOnSession

Methods inherited from class uk.co.weft.maybeupload.MaybeUploadServlet

doDelete, doHead, doOptions, doPut, doTrace, getUploadDir, getUploadURL, service

Methods inherited from class javax.servlet.http.HttpServlet

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

Methods inherited from class javax.servlet.GenericServlet

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

Methods inherited from class java.lang.Object

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

Field Detail

TITLEMAGICTOKEN

public static final java.lang.String TITLEMAGICTOKEN

a magic token to allow my title to be extracted from the context

See Also:

Constant Field Values

STYLESHEETCONFIGTOKEN

public static final java.lang.String STYLESHEETCONFIGTOKEN

a magic token on which we will seek in the configuration for the URL of the stylesheet for media="screen"

See Also:

Constant Field Values

PRINTSTYLESHEETCONFIGTOKEN

public static final java.lang.String PRINTSTYLESHEETCONFIGTOKEN

a magic token on which we will seek in the configuration for the URL of the stylesheet for media="print"

See Also:

Constant Field Values

DOCTYPECONFIGTOKEN

public static final java.lang.String DOCTYPECONFIGTOKEN

a magic token on which we will seek the value of the document type declaration in the configuration

See Also:

Constant Field Values

dynamicFootInclude

protected java.lang.Boolean dynamicFootInclude

whether the fragment should be refetched at each request (we really don't want to have to do this

Since:

Jacquard 1.9

dynamicHeadInclude

protected java.lang.Boolean dynamicHeadInclude

whether the fragment should be refetched at each request (we really don't want to have to do this

footInclude

protected java.lang.String footInclude

an HTML fragment to include at the beginning of the body of each page

Since:

Jacquard 1.9

headInclude

protected java.lang.String headInclude

an HTML fragment to include at the beginning of the body of each page

imageUrlBase

protected java.lang.String imageUrlBase

the base URL for utility images I may need

Since:

Jacquard 1.10

title

protected java.lang.String title

my title.

See Also:

getTitle()

titleMagicToken

protected final java.lang.String titleMagicToken

Deprecated. use TITLEMAGICTOKEN

a magic token to allow my title to be extracted from the context

See Also:

Constant Field Values

layout

protected Layout layout

My layout engine.

See Also:

Layout

footIncludeURL

protected java.lang.String footIncludeURL

the URL from which that fragment should be fetched

Since:

Jacquard 1.9

headIncludeURL

protected java.lang.String headIncludeURL

the URL from which that fragment should be fetched

printStylesheet

protected java.lang.String printStylesheet

The URL of my print stylsheet

stylesheet

protected java.lang.String stylesheet

The URI of my stylesheet

Constructor Detail

Page

public Page()

Method Detail

getLayout

public Layout getLayout(Context context)
                 throws javax.servlet.ServletException

Return my layout engine for this context. Currently only used by Form and it's subclasses, but defined here because later is may not be.

Parameters:

context - is passed because later we may want to use different layout engines for different browsers (or, conceivably, different levels of security clearance or whatever)

Throws:

javax.servlet.ServletException

See Also:

Layout

getStylesheets

public java.util.Vector getStylesheets(Context context)
                                throws java.lang.Exception

get the URLs of multiple stylesheets to use in this context. Default just returns a vector wrapped around the output of getStylesheet(Context).

Parameters:

context - the context of this service

Returns:

a vector all of whose members are URLs or string representations of URLs, all of which point to CSS stylesheets. Must return a vector (even if empty) rather than null.

Throws:

java.lang.Exception

Since:

Jacquard 1.9

init

public void init(Context config)
          throws InitialisationException

Initialisation: Set up my variables from my configuration.

Overrides:

init in class WithExceptionHandlerServlet

Throws:

InitialisationException

getFootInclude

protected java.lang.String getFootInclude(Context context)

fetch the foot include (if any) for this context. You probably don't want to specialise this; you probably want to specialise getFootIncludeURL.

Parameters:

context - the context for this service

Returns:

a string representing the HTML fragment to be spliced in

Since:

Jacquard 1.9

getFootIncludeURL

protected java.net.URL getFootIncludeURL(java.net.URL dflt,
                                         Context context)
                                  throws java.lang.Exception

If you're using dynamic foot includes, you probably want to specialise to generate a URL based on something in the context.

Parameters:

dflt - the default URL to return if you don't find anything interesting in the context

context - the context for this service.

Throws:

java.lang.Exception - not actually thrown, but things which specialise this may throw anything.

Since:

Jacquard 1.9

getFootIncludeURL

protected java.net.URL getFootIncludeURL(java.lang.String dflt,
                                         Context context)
                                  throws java.lang.Exception

If you're using dynamic foot includes, you probably want to specialise to generate a URL based on something in the context.

Parameters:

dflt - the default URL to return if you don't find anything interesting in the context

context - the context for this service.

Throws:

java.lang.Exception - not actually thrown, but things which specialise this may throw anything.

Since:

Jacquard 1.9

getHeadInclude

protected java.lang.String getHeadInclude(Context context)

fetch the head include (if any) for this context. You probably don't want to specialise this; you probably want to specialise getHeadIncludeURL.

Parameters:

context - the context for this service

Returns:

a string representing the HTML fragment to be spliced in

getHeadIncludeURL

protected java.net.URL getHeadIncludeURL(java.net.URL dflt,
                                         Context context)
                                  throws java.lang.Exception

Deprecated. replaced with getHeadIncludeURL(String,Context) which is able to fix up relative URLs

If you're using dynamic head includes, you probably want to specialise to generate a URL based on something in the context.

Parameters:

dflt - the default URL to return if you don't find anything interesting in the context

context - the context for this service.

Throws:

java.lang.Exception - not actually thrown, but things which specialise this may throw anything.

getHeadIncludeURL

protected java.net.URL getHeadIncludeURL(java.lang.String dflt,
                                         Context context)
                                  throws java.lang.Exception

If you're using dynamic head includes, you probably want to specialise to generate a URL based on something in the context.

Parameters:

dflt - the default URL to return if you don't find anything interesting in the context

context - the context for this service.

Throws:

java.lang.Exception - not actually thrown, but things which specialise this may throw anything.

getStylesheet

protected java.lang.String getStylesheet(Context context)
                                  throws java.lang.Exception

Deprecated. probably better to use getStylesheets(Context)

get the style sheet to use in this context; a hack, needs rethought in the light of separate layout engines. Default just returns the value of the stylesheet iv

Throws:

java.lang.Exception

getTables

protected boolean getTables()

return the value of my tables iv

getTitle

protected java.lang.String getTitle()

Deprecated. use getTitle( Context) in preference

construct and return a suitable title for this form.

getTitle

protected java.lang.String getTitle(Context context)

construct and return a suitable title for this page in this context.

Parameters:

context - the context for this service

Returns:

a suitable title string for this page for this service

doBody

protected abstract void doBody(Context context)
                        throws java.lang.Exception

Specialise! Do not use! Output what is to appear on your page between (but not including) the BODY tags.

Throws:

java.lang.Exception

doFoot

protected void doFoot(Context context)
               throws java.lang.Exception

Output standardised footer.

Throws:

java.lang.Exception

doFoot

protected void doFoot(Context context,
                      java.lang.String message)
               throws java.lang.Exception

output a footer onto my output stream, incorporating a supplied message.

Throws:

java.lang.Exception

doHead

protected void doHead(Context context)
               throws java.lang.Exception

Output an HTML HEAD section, up to but not including the closing /HEAD tag. The reason for not including it is to allow specialisations to start with super.doHead(), before emitting whatever head content they themselves need to emit.

Throws:

java.lang.Exception

doHeadBodySep

protected void doHeadBodySep(Context context)
                      throws java.lang.Exception

Output the close of the head tag and the opening of the body tag.

Throws:

java.lang.Exception

generateContent

protected void generateContent(Context context)
                        throws java.lang.Exception

Generate the content of a normal page, by generating first the head, then the body tag, then the body content. This is old code and the API is not very clean - I wouldn't do it this way now.

Specified by:

generateContent in class Servlet

Parameters:

context - the context for this service

Throws:

java.lang.Exception - actually does not throw any exception, but conforms to an API which may

outputRedirectBlock

protected void outputRedirectBlock(Context context)
                            throws java.io.IOException

Output a stub HTML page with a 'refresh' meta. Should be redundent, because only output it a type 302 response has already been sent, so should never be seen... but does no harm

Overrides:

outputRedirectBlock in class Servlet

Parameters:

context - the context for this service

Throws:

java.io.IOException - if output barfs.

readStringFromURL

protected java.lang.String readStringFromURL(java.net.URL source)
                                      throws java.io.IOException

read the value at this URL and return it as a string

Parameters:

source - where to read from

Returns:

a string representation of the data fetched from the URL

Throws:

java.io.IOException

Since:

Jacquard 1.9