PageProvider (Wicket Core 8.0.0-M9 API)

java.lang.Object
- org.apache.wicket.core.request.handler.PageProvider

All Implemented Interfaces:

Serializable, IPageProvider, org.apache.wicket.util.io.IClusterable

Direct Known Subclasses:

PageAndComponentProvider
```
public class PageProvider
extends Object
implements IPageProvider, org.apache.wicket.util.io.IClusterable
```
Provides page instance for request handlers. Each of the constructors has just enough information to get existing or create new page instance. Requesting or creating page instance is deferred until getPageInstance() is called.
Purpose of this class is to reduce complexity of both IRequestMappers and IRequestHandlers. IRequestMapper examines the URL, gathers all relevant information about the page in the URL (combination of page id, page class, page parameters and render count), creates PageProvider object and creates a IRequestHandler instance that can use the PageProvider to access the page.
Apart from simplifying IRequestMappers and IRequestHandlers PageProvider also helps performance because creating or obtaining page from IPageManager is delayed until the IRequestHandler actually requires the page.

Author:

Matej Knopp

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description
`PageProvider(Class<? extends IRequestablePage> pageClass)` Creates a new page provider object.
`PageProvider(Class<? extends IRequestablePage> pageClass, org.apache.wicket.request.mapper.parameter.PageParameters pageParameters)` Creates a new page provider object.
`PageProvider(Integer pageId, Class<? extends IRequestablePage> pageClass, Integer renderCount)` Creates a new page provider object.
`PageProvider(Integer pageId, Class<? extends IRequestablePage> pageClass, org.apache.wicket.request.mapper.parameter.PageParameters pageParameters, Integer renderCount)` Creates a new page provider object.
`PageProvider(Integer pageId, Integer renderCount)` Creates a new page provider object.
`PageProvider(IRequestablePage page)` Creates a new page provider object.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`void`	`detach()` Detaches the page if it has been loaded (that means either `PageProvider(IRequestablePage)` constructor has been used or `getPageInstance()` has been called).
`boolean`	`doesProvideNewPage()` Returns whether or not the page instance held by this provider has been instantiated by the provider.
`Class<? extends IRequestablePage>`	`getPageClass()` Returns class of the page.
`Integer`	`getPageId()` Returns the page id.
`IRequestablePage`	`getPageInstance()` Returns page instance specified by the constructor.
`org.apache.wicket.request.mapper.parameter.PageParameters`	`getPageParameters()` Returns `PageParameters` of the page.
`protected IPageSource`	`getPageSource()`
`Integer`	`getRenderCount()` Returns the number of times this page has been rendered.
`boolean`	`hasPageInstance()` If this provider returns existing page, regardless if it was already created by PageProvider itself or is or can be found in the data store.
`boolean`	`isNewPageInstance()` Deprecated. use `hasPageInstance()` negation instead
`protected void`	`setPageParameters(org.apache.wicket.request.mapper.parameter.PageParameters pageParameters)`
`void`	`setPageSource(IPageSource pageSource)` If the `PageProvider` is used outside request thread (thread that does not have application instance assigned) it is necessary to specify a `IPageSource` instance so that `PageProvider` knows how to get a page instance.
`String`	`toString()`
`boolean`	`wasExpired()` Returns whether the provided page was expired prior to this access.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - PageProvider
```
public PageProvider(Integer pageId,
                    Integer renderCount)
```
    Creates a new page provider object. Upon calling of getPageInstance() this provider will return page instance with specified id.
    
    Parameters:
    
    pageId -
    
    renderCount - optional argument
  - PageProvider
```
public PageProvider(Integer pageId,
                    Class<? extends IRequestablePage> pageClass,
                    Integer renderCount)
```
    Creates a new page provider object. Upon calling of getPageInstance() this provider will return page instance with specified id if it exists and it's class matches pageClass. If none of these is true new page instance will be created.
    
    Parameters:
    
    pageId -
    
    pageClass -
    
    renderCount - optional argument
  - PageProvider
```
public PageProvider(Integer pageId,
                    Class<? extends IRequestablePage> pageClass,
                    org.apache.wicket.request.mapper.parameter.PageParameters pageParameters,
                    Integer renderCount)
```
    Creates a new page provider object. Upon calling of getPageInstance() this provider will return page instance with specified id if it exists and it's class matches pageClass. If none of these is true new page instance will be created.
    
    Parameters:
    
    pageId -
    
    pageClass -
    
    pageParameters -
    
    renderCount - optional argument
  - PageProvider
```
public PageProvider(Class<? extends IRequestablePage> pageClass,
                    org.apache.wicket.request.mapper.parameter.PageParameters pageParameters)
```
    Creates a new page provider object. Upon calling of getPageInstance() this provider will return new instance of page with specified class.
    
    Parameters:
    
    pageClass -
    
    pageParameters -
  - PageProvider
```
public PageProvider(Class<? extends IRequestablePage> pageClass)
```
    Creates a new page provider object. Upon calling of getPageInstance() this provider will return new instance of page with specified class.
    
    Parameters:
    
    pageClass -
  - PageProvider
```
public PageProvider(IRequestablePage page)
```
    Creates a new page provider object. Upon calling of getPageInstance() this provider will return the given page instance.
    
    Parameters:
    
    page -
- Method Detail
  - getPageInstance
```
public IRequestablePage getPageInstance()
                                 throws PageExpiredException
```
    Description copied from interface: IPageProvider
    
    Returns page instance specified by the constructor.
    
    Specified by:
    
    getPageInstance in interface IPageProvider
    
    Returns:
    
    page instance
    
    Throws:
    
    PageExpiredException - if the specified page could not have been found and the constructor used did not provide enough information to create new page instance
  - getPageParameters
```
public org.apache.wicket.request.mapper.parameter.PageParameters getPageParameters()
                                                                            throws PageExpiredException
```
    Description copied from interface: IPageProvider
    
    Returns PageParameters of the page.
    
    Specified by:
    
    getPageParameters in interface IPageProvider
    
    Returns:
    
    page parameters
    
    Throws:
    
    PageExpiredException - if the specified page could not have been found and the constructor used did not provide enough information to create new page instance
  - isNewPageInstance
```
public boolean isNewPageInstance()
```
    Deprecated. use hasPageInstance() negation instead
    
    Specified by:
    
    isNewPageInstance in interface IPageProvider
    
    Returns:
    
    negates hasPageInstance()
  - hasPageInstance
```
public final boolean hasPageInstance()
```
    If this provider returns existing page, regardless if it was already created by PageProvider itself or is or can be found in the data store. The only guarantee is that by calling getPageInstance() this provider will return an existing instance and no page will be created.
    
    Specified by:
    
    hasPageInstance in interface IPageProvider
    
    Returns:
    
    if provides an existing page
  - doesProvideNewPage
```
public final boolean doesProvideNewPage()
```
    Returns whether or not the page instance held by this provider has been instantiated by the provider.
    
    Specified by:
    
    doesProvideNewPage in interface IPageProvider
    
    Returns:
    
    true iff the page instance held by this provider was instantiated by the provider
  - wasExpired
```
public boolean wasExpired()
```
    Description copied from interface: IPageProvider
    
    Returns whether the provided page was expired prior to this access.
    
    Specified by:
    
    wasExpired in interface IPageProvider
    
    Returns:
    
    true> if the page was created after its original instance expired.
  - getPageClass
```
public Class<? extends IRequestablePage> getPageClass()
                                               throws PageExpiredException
```
    Description copied from interface: IPageProvider
    
    Returns class of the page.
    
    Specified by:
    
    getPageClass in interface IPageProvider
    
    Returns:
    
    page class
    
    Throws:
    
    PageExpiredException - if the specified page could not have been found and the constructor used did not provide enough information to create new page instance
  - getPageSource
```
protected IPageSource getPageSource()
```
  - detach
```
public void detach()
```
    Detaches the page if it has been loaded (that means either PageProvider(IRequestablePage) constructor has been used or getPageInstance() has been called).
    
    Specified by:
    
    detach in interface IPageProvider
  - setPageSource
```
public void setPageSource(IPageSource pageSource)
```
    If the PageProvider is used outside request thread (thread that does not have application instance assigned) it is necessary to specify a IPageSource instance so that PageProvider knows how to get a page instance.
    
    Parameters:
    
    pageSource -
  - setPageParameters
```
protected void setPageParameters(org.apache.wicket.request.mapper.parameter.PageParameters pageParameters)
```
    Parameters:
    
    pageParameters -
  - getPageId
```
public Integer getPageId()
```
    Description copied from interface: IPageProvider
    
    Returns the page id.
    
    Specified by:
    
    getPageId in interface IPageProvider
    
    Returns:
    
    page id
  - getRenderCount
```
public Integer getRenderCount()
```
    Description copied from interface: IPageProvider
    
    Returns the number of times this page has been rendered.
    
    Specified by:
    
    getRenderCount in interface IPageProvider
    
    Returns:
    
    the number of times this page has been rendered.
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class PageProvider

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

PageProvider

PageProvider

PageProvider

PageProvider

PageProvider

PageProvider

Method Detail

getPageInstance

getPageParameters

isNewPageInstance

hasPageInstance

doesProvideNewPage

wasExpired

getPageClass

getPageSource

detach

setPageSource

setPageParameters

getPageId

getRenderCount

toString