de.must.markup

Class JspButler

java.lang.Object

de.must.middle.ExemptibleManagerImplementation

de.must.markup.JspButler

All Implemented Interfaces:

Exemptible, ExemptibleManager

Direct Known Subclasses:

LoginJspButlerStd

public abstract class JspButler
extends ExemptibleManagerImplementation

Butler for JavaServerPages. Try to put as much as you can outside the JSP and into a butler class. In simple cases, you don't need more. Anyhow, it's good to use butler classes via JspSession classes. Why is it called butler? Just bean may be everything! This butler bean is a kind of server of the JSP which makes its live easy - just like a butler of a real person.

See Also:

JspSessionStd

Field Summary

Fields

Modifier and Type	Field and Description
BackButton	backButton An object that provides to represent a button with go back functionality.
static java.lang.String	FURTHER_PARAMETER_DELIMITER
static java.lang.String	HIDDEN_PANEL_FIELD
protected SessionData	sessionData

Constructor Summary

Constructors

Constructor and Description
JspButler(SessionData sessionData) Constructs a new JSP butler with the session's public data as specified.

Method Summary

Modifier and Type	Method and Description
HalfDataComboBox	createComboBox(SessionData sessionData, java.lang.String name, DataObject contentDataObject, java.lang.String visibleColumn, java.lang.String orderByColumn, java.lang.String nameForNoChoice) Creates a combo box.
MustPasswordField	createPasswordField(int length)
MustTextField	createTextField(int length)
boolean	didUserChangeSomethingSinceLastOkOrCancel() Returns true if user changed something since last OK or Cancel.
java.lang.String	encode(java.lang.String url)
java.lang.String	encodeRedirectURL(java.lang.String url) Encodes the specified URL for use in the sendRedirect method or, if encoding is not needed, returns the URL unchanged.
protected void	finalize()
java.lang.String	getAlertableString(java.lang.String stringToBeAlerted) Returns a string which may be used in a JavaScript alert function.
protected java.lang.Class<?>[]	getButlerFriends() Returns an array of chummy butlers - used to exclude them from reducing butler cache.
int	getComeInDialogNbr() Returns the dialog number identified by hidden field in JSP.
int	getCurrentDialogNbr()
int	getDialogNbr() Returns the nbr of the session's current dialog sequence.
java.lang.String	getDialogNumberHiddenFieldTag()
java.lang.String	getDialogNumberUrlFragment()
java.lang.String	getFieldNameToReceiveFocus() Returns the name of the field to receive the focus.
protected java.lang.String	getHrefTag(java.lang.String target)
protected java.lang.String	getHrefTag(java.lang.String target, boolean openInNewWindow)
long	getLastUse() Returns the last usage of the butler as current time in milliseconds.
java.lang.String	getPreviousURI() Returns the URI of the previous served page.
java.lang.String	getScriptToExecute() Returns the JavaScript to be executed.
protected java.lang.Object	getSychronizationObject()
java.lang.String	getTranslationByFramework(java.lang.String key)
java.lang.String	getURI() Returns the URI of the current served page.
int	getWindowNbr() Returns the window number
protected void	goBack() Causes the butler to return to the previous page.
protected void	handle(GeneralizedRequest request) React on user input and prepare objects to be visualized in the JSP via this method.
boolean	handlingCausesReturn(HttpServletRequest request, HttpServletResponse response) To be called by the JSP before any output was created.
protected void	informUserAbout(java.lang.Exception exc) Informs the user about an exception.
void	init() Called by SessionStd if the previous butler class was different.
protected void	invalidate() Invalidates the butler to remove it from cache.
boolean	isCloseWindowIfNoPreviousURIisAvailable() Returns the closeWindowIfNoPreviousURIisAvailable.
protected boolean	isExactDialogSequence() Returns true if the request comes from exactly the last preparation of this butler.
boolean	isInvalidated() Return true if the butler has been invalidated.
boolean	isPreviousURIAvailable()
boolean	isToRun() Returns the toRun flag.
void	jspDestroyConsequences() Consequences when JSP has been destroyed by Tomcat.
void	setCloseWindowIfNoPreviousURIisAvailable(boolean closeWindowIfNoPreviousURIisAvailable) Sets the closeWindowIfNoPreviousURIisAvailable.
protected void	setFocusOn(MustInputField field) Sets the focus on the input field - needs client JavaScript to set the focus.
void	setForeignPreparationFlag() Indicates that the butler has been prepared from outside, e.g. by another butler.
void	setMessageToKeep(java.lang.String message) Sets the message to be read by the user.
void	setToRun(boolean newToRun) Set's the toRun flag.
protected void	setUriToGo(java.lang.String newUriToGo) Set's the URI to go next.
void	setUserChangesSinceLastOkOrCancel(boolean userChanges) Sets the flag indicating that user changed something since last OK or Cancel.
void	setWindowNbr(int windowNbr) Sets the windowNbr.

Methods inherited from class de.must.middle.ExemptibleManagerImplementation

free, register

Methods inherited from class java.lang.Object

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

Field Detail

HIDDEN_PANEL_FIELD

public static final java.lang.String HIDDEN_PANEL_FIELD

See Also:

TabButtonGroup.fetchYourValueFromRequest(de.must.markup.GeneralizedRequest), Constant Field Values

FURTHER_PARAMETER_DELIMITER

public static final java.lang.String FURTHER_PARAMETER_DELIMITER

See Also:

Constant Field Values

backButton

public BackButton backButton

An object that provides to represent a button with go back functionality. This is not the same thing as history back function. Instead the button supports to go back to the page that called the current page the first time. Use it like that:

 <%=butler.backButton%>
 

sessionData

protected SessionData sessionData

Constructor Detail

JspButler

public JspButler(SessionData sessionData)

Constructs a new JSP butler with the session's public data as specified.

Parameters:

sessionData - the session's public data

Method Detail

isCloseWindowIfNoPreviousURIisAvailable

public boolean isCloseWindowIfNoPreviousURIisAvailable()

Returns the closeWindowIfNoPreviousURIisAvailable.

Returns:

boolean

setCloseWindowIfNoPreviousURIisAvailable

public void setCloseWindowIfNoPreviousURIisAvailable(boolean closeWindowIfNoPreviousURIisAvailable)

Sets the closeWindowIfNoPreviousURIisAvailable.

Parameters:

closeWindowIfNoPreviousURIisAvailable - The closeWindowIfNoPreviousURIisAvailable to set

getWindowNbr

public int getWindowNbr()

Returns the window number

Returns:

the window number

setWindowNbr

public void setWindowNbr(int windowNbr)

Sets the windowNbr.

Parameters:

windowNbr - The windowNbr to set

setForeignPreparationFlag

public void setForeignPreparationFlag()

Indicates that the butler has been prepared from outside, e.g. by another butler. Avoids the handle method to be called. Useful e.g. for continued load from a calling butler. Sample: if the calling butler did already cause the called butler to refresh all objects, there's no need to do it again. Also, there are no values to be fetched from the request.

init

public void init()

Called by SessionStd if the previous butler class was different.

See Also:

JspSessionStd.getButler(java.lang.Class<? extends de.must.markup.JspButler>)

getSychronizationObject

protected java.lang.Object getSychronizationObject()

createTextField

public MustTextField createTextField(int length)

createPasswordField

public MustPasswordField createPasswordField(int length)

createComboBox

public HalfDataComboBox createComboBox(SessionData sessionData,
                                       java.lang.String name,
                                       DataObject contentDataObject,
                                       java.lang.String visibleColumn,
                                       java.lang.String orderByColumn,
                                       java.lang.String nameForNoChoice)

Creates a combo box.

Parameters:

sessionData - the session's public data

name - the name of the combo box

contentDataObject - the source data object that shall fill the content of the combo box

visibleColumn - the column to be used to fill the combo box from the source data object

orderByColumnName - the column name to determine for the list order

nameForNoChoice - the expression that indicates "no choice"

Returns:

the created combo box

handlingCausesReturn

public boolean handlingCausesReturn(HttpServletRequest request,
                                    HttpServletResponse response)
                             throws java.io.IOException,
                                    ServletException

To be called by the JSP before any output was created. It's recommended to do it via include afterbf.jspf, which means after butler fetch.

 <% if (butler.handlingCausesReturn(request, response)) return;%>
 

Returns:

true if there is no need to build the page - e.g. because a redirect was caused.

Throws:

java.io.IOException

ServletException

getTranslationByFramework

public java.lang.String getTranslationByFramework(java.lang.String key)

getCurrentDialogNbr

public int getCurrentDialogNbr()

getButlerFriends

protected java.lang.Class<?>[] getButlerFriends()

Returns an array of chummy butlers - used to exclude them from reducing butler cache. E.g. you may declare these butlers as friends: - the sequence of all butlers in stack calling you - all butlers you are calling to avoid unwanted initialization

Returns:

an array of chummy butlers

handle

protected void handle(GeneralizedRequest request)

React on user input and prepare objects to be visualized in the JSP via this method. E.g you may ask an OK button, if it's pressed. Or you may load data into a group of storables.

Parameters:

request - the request to be handled

getDialogNbr

public int getDialogNbr()

Returns the nbr of the session's current dialog sequence. This nbr may be stored in a hidden field named "dialogNbr" to verify whether the incoming request parameters belong to the butler or not.

Returns:

the nbr of the session's current dialog sequence

See Also:

isExactDialogSequence()

isExactDialogSequence

protected boolean isExactDialogSequence()

Returns true if the request comes from exactly the last preparation of this butler. Tastes like "do you feel responsible to deal incoming data?". Needs a hidden field in JSP as follows:

Returns:

true if the request comes from exactly the last preparation of this butler

See Also:

getDialogNumberHiddenFieldTag()

getComeInDialogNbr

public int getComeInDialogNbr()

Returns the dialog number identified by hidden field in JSP.

Returns:

the dialog number identified by hidden field in JSP

setToRun

public void setToRun(boolean newToRun)

Set's the toRun flag. This is an opportunity to exit loops if the JSP response isn't needed any more.

Parameters:

newToRun - whether the butler's activity is to continue or not.

isToRun

public boolean isToRun()

Returns the toRun flag. This is an opportunity to exit loops if the JSP response isn't needed any more.

Returns:

toRun whether the butler's activity is to continue or not.

setUriToGo

protected void setUriToGo(java.lang.String newUriToGo)

Set's the URI to go next.

Parameters:

newUriToGo - the URI to go next.

isPreviousURIAvailable

public boolean isPreviousURIAvailable()

goBack

protected void goBack()

Causes the butler to return to the previous page. This is not identical with the previous page in document history! It's the page which called the current page for the first time. Sample: If you have been searching for records, you found more than one matching records, you might view details repeatedly. Nevertheless, the list's back button will lead you to the search criteria input page.

getURI

public java.lang.String getURI()

Returns the URI of the current served page.

Returns:

the URI of the current served page

getPreviousURI

public java.lang.String getPreviousURI()

Returns the URI of the previous served page.

Returns:

the URI of the previous served page

getHrefTag

protected java.lang.String getHrefTag(java.lang.String target)

getHrefTag

protected java.lang.String getHrefTag(java.lang.String target,
                                      boolean openInNewWindow)

encode

public java.lang.String encode(java.lang.String url)

encodeRedirectURL

public java.lang.String encodeRedirectURL(java.lang.String url)

Encodes the specified URL for use in the sendRedirect method or, if encoding is not needed, returns the URL unchanged. The implementation of this method includes the logic to determine whether the session ID needs to be encoded in the URL. Because the rules for making this determination can differ from those used to decide whether to encode a normal link, this method is separate from the encodeURL method.

Parameters:

the - URL to be encoded

Returns:

the encoded URL if encoding is needed; the unchanged URL otherwise

informUserAbout

protected void informUserAbout(java.lang.Exception exc)

Informs the user about an exception.

Parameters:

exc - exception the user should be informed about

setFocusOn

protected void setFocusOn(MustInputField field)

Sets the focus on the input field - needs client JavaScript to set the focus. Sample:

function shallIsetFocus() {
<% if (butler.getFieldNameToReceiveFocus() != null) { %>
 for (var i = 0; i < window.document.forms[0].elements.length; i++) {
  var e = window.document.forms[0].elements[i];
  if (e.name == "<%=butler.getFieldNameToReceiveFocus()%>") {
   e.focus();
   break;
  }
 }
<% } %>
}
...

 

Parameters:

field - Sets the focus on the input field

See Also:

getFieldNameToReceiveFocus()

getFieldNameToReceiveFocus

public java.lang.String getFieldNameToReceiveFocus()

Returns the name of the field to receive the focus.

Returns:

the name of the field to receive the focus

getDialogNumberHiddenFieldTag

public java.lang.String getDialogNumberHiddenFieldTag()

getDialogNumberUrlFragment

public java.lang.String getDialogNumberUrlFragment()

setMessageToKeep

public void setMessageToKeep(java.lang.String message)

Sets the message to be read by the user.

Parameters:

messageToKeep - the message for the user

getScriptToExecute

public java.lang.String getScriptToExecute()

Returns the JavaScript to be executed.

Returns:

the JavaScript to be executed

getAlertableString

public java.lang.String getAlertableString(java.lang.String stringToBeAlerted)

Returns a string which may be used in a JavaScript alert function.

Parameters:

stringToBeAlerted - the string to be alerted

Returns:

a string which may be used in a JavaScript alert function

setUserChangesSinceLastOkOrCancel

public void setUserChangesSinceLastOkOrCancel(boolean userChanges)

Sets the flag indicating that user changed something since last OK or Cancel.

Parameters:

whether - or not user changed something since last OK or Cancel.

didUserChangeSomethingSinceLastOkOrCancel

public boolean didUserChangeSomethingSinceLastOkOrCancel()

Returns true if user changed something since last OK or Cancel.

Returns:

true if user changed something since last OK or Cancel

getLastUse

public long getLastUse()

Returns the last usage of the butler as current time in milliseconds.

Returns:

the last usage of the butler as current time in milliseconds

invalidate

protected void invalidate()

Invalidates the butler to remove it from cache. Since multiple windows per session may be provided by separate butlers, database cursors may be opened numerously. To avoid cursor exception, override this method and call free() for each used data object. Although the garbage collector does this job too, it may be not deterministic enough.

isInvalidated

public boolean isInvalidated()

Return true if the butler has been invalidated. Used to remove it from cache.

Returns:

rue if the butler has been invalidated

jspDestroyConsequences

public void jspDestroyConsequences()

Consequences when JSP has been destroyed by Tomcat. jspDestroy() seems to be called by Tomcat only when application is stopped.

finalize

protected void finalize()
                 throws java.lang.Throwable

Overrides:

finalize in class java.lang.Object

Throws:

java.lang.Throwable