org.apache.wicket
Class Page

java.lang.Object
  org.apache.wicket.Component
      org.apache.wicket.MarkupContainer
          org.apache.wicket.Page

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<Component>, IEventSink, IEventSource, IClusterable, IConverterLocator, IRedirectListener, IRequestListener, IHeaderContributor, IManageablePage, IRequestableComponent, IRequestablePage, IHierarchical<Component>

Direct Known Subclasses:

WebPage

public abstract class Page
extends MarkupContainer
implements IRedirectListener, IRequestablePage

Abstract base class for pages. As a MarkupContainer subclass, a Page can contain a component hierarchy and markup in some markup language such as HTML. Users of the framework should not attempt to subclass Page directly. Instead they should subclass a subclass of Page that is appropriate to the markup type they are using, such as WebPage (for HTML markup).

• Construction - When a page is constructed, it is automatically added to the current PageMap in the Session. When a Page is added to the Session's PageMap, the PageMap assigns the Page an id. A PageMap is roughly equivalent to a browser window and encapsulates a set of pages accessible through that window. When a popup window is created, a new PageMap is created for the popup.
• Identity - The Session that a Page is contained in can be retrieved by calling Page.getSession(). Page identifiers start at 0 for each PageMap in the Session and increment as new pages are added to the map. The PageMap-(and Session)-unique identifier assigned to a given Page can be retrieved by calling getId(). So, the first Page added to a new user Session will always be named "0".
• LifeCycle - Subclasses of Page which are interested in lifecycle events can override onBeginRequest, onEndRequest() and onModelChanged(). The onBeginRequest() method is inherited from Component. A call to onBeginRequest() is made for every Component on a Page before page rendering begins. At the end of a request (when rendering has completed) to a Page, the onEndRequest() method is called for every Component on the Page.
• Nested Component Hierarchy - The Page class is a subclass of MarkupContainer. All MarkupContainers can have "associated markup", which resides alongside the Java code by default. All MarkupContainers are also Component containers. Through nesting, of containers, a Page can contain any arbitrary tree of Components. For more details on MarkupContainers, see MarkupContainer.
• Bookmarkable Pages - Pages can be constructed with any constructor when they are being used in a Wicket session, but if you wish to link to a Page using a URL that is "bookmarkable" (which implies that the URL will not have any session information encoded in it, and that you can call this page directly without having a session first directly from your browser), you need to implement your Page with a no-arg constructor or with a constructor that accepts a PageParameters argument (which wraps any query string parameters for a request). In case the page has both constructors, the constructor with PageParameters will be used.
• Models - Pages, like other Components, can have models (see IModel). A Page can be assigned a model by passing one to the Page's constructor, by overriding initModel() or with an explicit invocation of setModel(). If the model is a CompoundPropertyModel, Components on the Page can use the Page's model implicitly via container inheritance. If a Component is not assigned a model, the initModel() override in Component will cause that Component to use the nearest CompoundModel in the parent chain, in this case, the Page's model. For basic CompoundModels, the name of the Component determines which property of the implicit page model the component is bound to. If more control is desired over the binding of Components to the page model (for example, if you want to specify some property expression other than the component's name for retrieving the model object), BoundCompoundPropertyModel can be used.
• Back Button - Pages can support the back button by enabling versioning with a call to setVersioned(boolean). If a Page is versioned and changes occur to it which need to be tracked, a version manager will be installed using the ISessionStore's factory method newVersionManager().
• Security - See IAuthorizationStrategy, SimplePageAuthorizationStrategy

  Author:

  Jonathan Locke, Chris Turner, Eelco Hillenius, Johan Compagner

  See Also:

  WebPage, MarkupContainer, CompoundPropertyModel, Component, Serialized Form

  Field Summary

  Fields inherited from class org.apache.wicket.Component

  ENABLE, FLAG_INITIALIZED, FLAG_REMOVING_FROM_HIERARCHY, FLAG_RESERVED1, FLAG_RESERVED2, FLAG_RESERVED3, FLAG_RESERVED4, FLAG_RESERVED5, FLAG_RESERVED8, PARENT_PATH, PATH_SEPARATOR, RENDER

  Fields inherited from interface org.apache.wicket.IRedirectListener

  INTERFACE

  Constructor Summary

  protected	Page() Constructor.
  protected	Page(IModel<?> model) Constructor.
  protected	Page(PageParameters parameters) The PageParameters parameter will be stored in this page and then those parameters will be used to create stateless links to this bookmarkable page.

  Method Summary

  protected void	componentChanged(Component component, MarkupContainer parent) This method will be called for all components that are changed on the page So also auto components or components that are not versioned.
  void	componentRendered(Component component) Adds a component to the set of rendered components.
  void	detachModels() Detaches any attached models referenced by this page.
  void	dirty()
  void	dirty(boolean isInitialization) Mark this page as modified in the session.
  void	endComponentRender(Component component) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  int	getAutoIndex() THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  java.lang.String	getId() Gets the id of this component.
  MarkupType	getMarkupType() Get the type of associated markup for this component.
  java.lang.Class<? extends Page>	getPageClass()
  int	getPageId()
  PageParameters	getPageParameters() The PageParameters object that was used to construct this page.
  PageReference	getPageReference() Gets page instance's unique identifier
  int	getRenderCount() Returns the number of times this page has been rendered.
  long	getSizeInBytes()
  boolean	getStatelessHint() Returns whether the page should try to be stateless.
  java.lang.String	hierarchyAsString()
  protected void	internalOnModelChanged() THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  void	internalPrepareForRender(boolean setRenderingFlag) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  boolean	isBookmarkable() Bookmarkable page can be instantiated using a bookmarkable URL.
  boolean	isErrorPage() Override this method and return true if your page is used to display Wicket errors.
  boolean	isPageStateless() Gets whether the page is stateless.
  protected void	onAfterRender() Called just after a component is rendered.
  protected void	onBeforeRender() Called just before a component is rendered.
  protected void	onDetach() Called to allow a component to detach resources after use.
  void	onRedirect() Redirect to this page.
  protected void	onRender() Implementation that renders this component.
  void	renderPage() Renders the page
  boolean	setFreezePageId(boolean freeze) Sets whether or not the page is allowed to change its page id.
  void	setNumericId(int id) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  void	setStatelessHint(boolean value) Sets whether the page should try to be stateless.
  void	setWasCreatedBookmarkable(boolean wasCreatedBookmarkable) TODO WICKET-NG javadoc
  void	startComponentRender(Component component) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  java.lang.String	toString() Get the string representation of this container.
  boolean	wasCreatedBookmarkable() TODO WICKET-NG javadoc
  boolean	wasRendered(Component component) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.

  Methods inherited from class org.apache.wicket.MarkupContainer

  add, addOrReplace, autoAdd, contains, get, get, getAssociatedMarkup, getAssociatedMarkupStream, getMarkup, hasAssociatedMarkup, internalAdd, internalInitialize, iterator, iterator, onAfterRenderChildren, onComponentTagBody, onMarkupAttached, remove, remove, removeAll, renderAll, renderAssociatedMarkup, renderNext, replace, setDefaultModel, size, swap, toString, visitChildren, visitChildren, visitChildren, visitChildren

  Methods inherited from class org.apache.wicket.Component

  add, addStateChange, afterRender, beforeRender, canCallListenerInterface, checkComponentTag, checkComponentTagAttribute, checkHierarchyChange, configure, continueToOriginalDestination, debug, detach, detachModel, determineVisibility, error, exceptionMessage, fatal, findMarkupStream, findPage, findParent, findParentWithAssociatedMarkup, getAjaxRegionMarkupId, getApplication, getBehaviorById, getBehaviorId, getBehaviors, getBehaviors, getClassRelativePath, getConverter, getDefaultModel, getDefaultModelObject, getDefaultModelObjectAsString, getDefaultModelObjectAsString, getEscapeModelStrings, getFeedbackMessage, getFeedbackMessages, getFlag, getInnermostModel, getInnermostModel, getLocale, getLocalizer, getMarkup, getMarkupAttributes, getMarkupId, getMarkupId, getMarkupIdFromMarkup, getMarkupIdImpl, getMarkupSourcingStrategy, getMetaData, getModelComparator, getOutputMarkupId, getOutputMarkupPlaceholderTag, getPage, getPageRelativePath, getParent, getPath, getRenderBodyOnly, getRequest, getRequestCycle, getRequestFlag, getResponse, getSession, getString, getString, getString, getStyle, getVariation, hasBeenRendered, hasErrorMessage, hasFeedbackMessage, info, initModel, internalRenderComponent, isActionAuthorized, isAuto, isBehaviorAccepted, isEnableAllowed, isEnabled, isEnabledInHierarchy, isIgnoreAttributeModifier, isRenderAllowed, isStateless, isVersioned, isVisibilityAllowed, isVisible, isVisibleInHierarchy, locateMarkupStream, markRendering, modelChanged, modelChanging, newMarkupSourcingStrategy, onComponentTag, onConfigure, onEvent, onInitialize, onModelChanged, onModelChanging, onRemove, prepareForRender, redirectToInterceptPage, remove, remove, render, renderComponentTag, rendered, renderHead, renderHead, renderHead, renderPlaceholderTag, replaceComponentTagBody, replaceWith, sameInnermostModel, sameInnermostModel, send, setAuto, setDefaultModelObject, setEnabled, setEscapeModelStrings, setFlag, setIgnoreAttributeModifier, setMarkup, setMarkupId, setMarkupIdImpl, setMetaData, setOutputMarkupId, setOutputMarkupPlaceholderTag, setParent, setRenderBodyOnly, setRequestFlag, setResponsePage, setResponsePage, setResponsePage, setVersioned, setVisibilityAllowed, setVisible, success, urlFor, urlFor, urlFor, urlFor, urlFor, visitParents, warn, wrap

  Methods inherited from class java.lang.Object

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

  Methods inherited from interface org.apache.wicket.request.component.IRequestableComponent

  canCallListenerInterface, detach, get, getBehaviorById, getBehaviorId, getPage, getPageRelativePath

  Methods inherited from interface org.apache.wicket.page.IManageablePage

  detach

  Constructor Detail

  Page

  protected Page()

  Constructor.

  Page

  protected Page(IModel<?> model)

  Constructor.

  Parameters:

  model - See Component

  See Also:

  Component.Component(String, IModel)

  Page

  protected Page(PageParameters parameters)

  The PageParameters parameter will be stored in this page and then those parameters will be used to create stateless links to this bookmarkable page.

  Parameters:

  parameters - externally passed parameters

  See Also:

  PageParameters

  Method Detail

  getPageParameters

  public PageParameters getPageParameters()

  The PageParameters object that was used to construct this page. This will be used in creating stateless/bookmarkable links to this page

  Specified by:

  getPageParameters in interface IRequestablePage

  Returns:

  PageParameters The construction page parameter

  componentRendered

  public final void componentRendered(Component component)

  Adds a component to the set of rendered components.

  Parameters:

  component - The component that was rendered

  detachModels

  public void detachModels()

  Detaches any attached models referenced by this page.

  Overrides:

  detachModels in class Component

  internalPrepareForRender

  public void internalPrepareForRender(boolean setRenderingFlag)

  Description copied from class: Component

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT USE IT!

  Prepares the component and it's children for rendering. On whole page render this method must be called on the page. On AJAX request, this method must be called on updated component.

  Overrides:

  internalPrepareForRender in class Component

  Parameters:

  setRenderingFlag - Whether to set the rendering flag. This must be true if the page is about to be rendered. However, there are usecases to call this method without an immediate render (e.g. on stateless listner request target to build the component hierarchy), in that case setRenderingFlag should be false

  See Also:

  Component.internalPrepareForRender(boolean)

  dirty

  public final void dirty()

  See Also:

  dirty(boolean)

  setFreezePageId

  public boolean setFreezePageId(boolean freeze)

  Sets whether or not the page is allowed to change its page id. Implementations of this interface usually change their page id once a change to the data structure is made and historical record of the current state needs to be kept (usually to be accessible via the back button). Keeping a historical record is usually achieved by simply incrementing the page id to the next unique number, so when the implementation is stored it is done so in a new slot. This method is useful when for some reason we do not want the implementation to change its page id under any circumstances. One concrete example is an AJAX request. Suppose the page with id 10 was written out with callbacks pointing to id 10. Suppose that the user executed some AJAX callbacks which have changed the page id to 15. Now, the user clicks a non-AJAX link that was never updated by an AJAX update and still points to id 10 - which causes the state of the page to be rolled back - which is usually undesirable as all changes made to the page by AJAX requests are lost. So, instead, whatever is invoking the execution of the AJAX request on the page can use this method to tell the page to not update its page id thereby solving the problem.

  Specified by:

  setFreezePageId in interface IManageablePage

  Returns:

  previous state

  dirty

  public void dirty(boolean isInitialization)

  Mark this page as modified in the session. If versioning is supported then a new version of the page will be stored in page store

  Parameters:

  isInitialization - a flag whether this is a page instantiation

  endComponentRender

  public final void endComponentRender(Component component)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL. This method is called when a component was rendered standalone. If it is a MarkupContainer then the rendering for that container is checked.

  Parameters:

  component -

  getAutoIndex

  public final int getAutoIndex()

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL IT. Get a page unique number, which will be increased with each call.

  Returns:

  A page unique number

  getId

  public final java.lang.String getId()

  Description copied from class: Component

  Gets the id of this component.

  Specified by:

  getId in interface IRequestableComponent

  Overrides:

  getId in class Component

  Returns:

  The id of this component

  See Also:

  Component.getId()

  getPageClass

  public final java.lang.Class<? extends Page> getPageClass()

  Returns:

  page class

  getSizeInBytes

  public final long getSizeInBytes()

  Overrides:

  getSizeInBytes in class Component

  Returns:

  Size of this page in bytes

  getStatelessHint

  public final boolean getStatelessHint()

  Returns whether the page should try to be stateless. To be stateless, getStatelessHint() of every component on page (and it's behavior) must return true and the page must be bookmarkable.

  Overrides:

  getStatelessHint in class Component

  Returns:

  whether the component can be stateless

  See Also:

  Component.getStatelessHint()

  hierarchyAsString

  public final java.lang.String hierarchyAsString()

  Returns:

  This page's component hierarchy as a string

  isBookmarkable

  public boolean isBookmarkable()

  Bookmarkable page can be instantiated using a bookmarkable URL.

  Specified by:

  isBookmarkable in interface IRequestablePage

  Returns:

  Returns true if the page is bookmarkable.

  isErrorPage

  public boolean isErrorPage()

  Override this method and return true if your page is used to display Wicket errors. This can help the framework prevent infinite failure loops.

  Returns:

  True if this page is intended to display an error to the end user.

  isPageStateless

  public final boolean isPageStateless()

  Gets whether the page is stateless. Components on stateless page must not render any stateful urls, and components on stateful page must not render any stateless urls. Stateful urls are urls, which refer to a certain (current) page instance.

  Specified by:

  isPageStateless in interface IManageablePage

  Returns:

  Whether this page is stateless

  onRedirect

  public final void onRedirect()

  Redirect to this page.

  Specified by:

  onRedirect in interface IRedirectListener

  See Also:

  IRedirectListener.onRedirect()

  setNumericId

  public final void setNumericId(int id)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL. Set the id for this Page. This method is called by PageMap when a Page is added because the id, which is assigned by PageMap, is not known until this time.

  Parameters:

  id - The id

  setStatelessHint

  public final void setStatelessHint(boolean value)

  Sets whether the page should try to be stateless. To be stateless, getStatelessHint() of every component on page (and it's behavior) must return true and the page must be bookmarkable.

  Parameters:

  value - whether the page should try to be stateless

  startComponentRender

  public final void startComponentRender(Component component)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL. This method is called when a component will be rendered standalone.

  Parameters:

  component -

  toString

  public java.lang.String toString()

  Get the string representation of this container.

  Overrides:

  toString in class MarkupContainer

  Returns:

  String representation of this container

  See Also:

  Component.toString()

  componentChanged

  protected void componentChanged(Component component,
                                  MarkupContainer parent)

  This method will be called for all components that are changed on the page So also auto components or components that are not versioned. If the parent is given that it was a remove or add from that parent of the given component. else it was just a internal property change of that component.

  Parameters:

  component -

  parent -

  internalOnModelChanged

  protected final void internalOnModelChanged()

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL OR OVERRIDE.

  Overrides:

  internalOnModelChanged in class Component

  See Also:

  Component.internalOnModelChanged()

  onBeforeRender

  protected void onBeforeRender()

  Description copied from class: Component

  Called just before a component is rendered.

  NOTE: If you override this, you *must* call super.onBeforeRender() within your implementation. Because this method is responsible for cascading Component.onBeforeRender() call to its children it is strongly recommended that super call is made at the end of the override.

  Overrides:

  onBeforeRender in class Component

  See Also:

  Component.onBeforeRender()

  onAfterRender

  protected void onAfterRender()

  Description copied from class: Component

  Called just after a component is rendered.

  Overrides:

  onAfterRender in class Component

  See Also:

  Component.onAfterRender()

  onDetach

  protected void onDetach()

  Description copied from class: Component

  Called to allow a component to detach resources after use. Overrides of this method MUST call the super implementation, the most logical place to do this is the last line of the override method.

  Overrides:

  onDetach in class Component

  See Also:

  Component.onDetach()

  onRender

  protected void onRender()

  Description copied from class: Component

  Implementation that renders this component.

  Overrides:

  onRender in class MarkupContainer

  See Also:

  MarkupContainer.onRender()

  getMarkupType

  public MarkupType getMarkupType()

  Description copied from class: MarkupContainer

  Get the type of associated markup for this component.

  Overrides:

  getMarkupType in class MarkupContainer

  Returns:

  The type of associated markup for this component (for example, "html", "wml" or "vxml"). The markup type for a component is independent of whether or not the component actually has an associated markup resource file (which is determined at runtime). If there is no markup type for a component, null may be returned, but this means that no markup can be loaded for the class. Null is also returned if the component, or any of its parents, has not been added to a Page.

  See Also:

  MarkupContainer.getMarkupType()

  getPageReference

  public PageReference getPageReference()

  Gets page instance's unique identifier

  Returns:

  instance unique identifier

  getPageId

  public int getPageId()

  Specified by:

  getPageId in interface IManageablePage

  Returns:

  A unique identifier for this page map entry

  See Also:

  IManageablePage.getPageId()

  getRenderCount

  public int getRenderCount()

  Description copied from interface: IRequestablePage

  Returns the number of times this page has been rendered. The number will be appended to listener interface links in order to prevent invoking listeners from staled page version.

  For example a same page might have been rendered in two separate tabs. Page render doesn't change page id but it can modify component hierarchy. Listener interface links on such page should only work in tab where the page was rendered most recently.

  Specified by:

  getRenderCount in interface IRequestablePage

  Returns:

  render count

  See Also:

  IRequestablePage.getRenderCount()

  setWasCreatedBookmarkable

  public final void setWasCreatedBookmarkable(boolean wasCreatedBookmarkable)

  TODO WICKET-NG javadoc

  Parameters:

  wasCreatedBookmarkable -

  wasCreatedBookmarkable

  public final boolean wasCreatedBookmarkable()

  TODO WICKET-NG javadoc

  Specified by:

  wasCreatedBookmarkable in interface IRequestablePage

  Returns:

  true if this page has been created by a bookmarkable URL, false otherwise.

  renderPage

  public void renderPage()

  Description copied from interface: IRequestablePage

  Renders the page

  Specified by:

  renderPage in interface IRequestablePage

  See Also:

  IRequestablePage.renderPage()

  wasRendered

  public final boolean wasRendered(Component component)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL.

  Parameters:

  component -

  Returns:

  if this component was render in this page