Package org.eclipse.ui.editors.text

## Class ForwardingDocumentProvider

- java.lang.Object
- - org.eclipse.ui.editors.text.ForwardingDocumentProvider

All Implemented Interfaces:
  `IStorageDocumentProvider`, `IDocumentProvider`, `IDocumentProviderExtension`, `IDocumentProviderExtension2`, `IDocumentProviderExtension3`, `IDocumentProviderExtension4`, `IDocumentProviderExtension5`

    public class ForwardingDocumentProvider
    extends Object
    implements IDocumentProvider, IDocumentProviderExtension, IDocumentProviderExtension2, IDocumentProviderExtension3, IDocumentProviderExtension4, IDocumentProviderExtension5, IStorageDocumentProvider

A forwarding document provider is a document provider that forwards all requests to a known parent document provider. The only functional addition of the forwarding document provider is that it ensures that all documents provided to clients are appropriately set up.

This document provider should be used by editors that directly or indirectly work with a `TextFileDocumentProvider` and do not accept that they may be provided with documents which do not contain the partitioning they work on. This can happen either because of a plug-in configuration error or when a user associates a file name or file extension with an existing text editor and the file buffer infrastructure does not recognize that file name or file extension to be of the same file type the editor works on. Thus, the document provided for the files with that name or extension may not be set up in the way the editor expects it. The `ForwardingDocumentProvider` compensates for that situation.

Editors that directly work with a `TextFileDocumentProvider` can now use a `ForwardingDocumentProvider` instead and configure a `TextFileDocumentProvider` as its parent provider. Editors that indirectly work with a `TextFileDocumentProvider`, e.g. never set a document provider explicitly, should explicitly set a `ForwardingDocumentProvider` as document provider. In this case the forwarding document provider may not be shared between editors.

Since:
  3.0

### Constructor Summary

Constructors
`ForwardingDocumentProvider​(String partitioning, IDocumentSetupParticipant documentSetupParticipant)` Creates a new forwarding document provider with a dynamically changeable parent provider.
`ForwardingDocumentProvider​(String partitioning, IDocumentSetupParticipant documentSetupParticipant, IDocumentProvider parentProvider)` Creates a new forwarding document provider with a fixed parent document provider.

### Method Summary

All Methods Instance Methods Concrete Methods
`void` `aboutToChange​(Object element)` Informs this document provider about upcoming changes of the given element.
`void` `addElementStateListener​(IElementStateListener listener)` Adds the given element state listener to this document provider.
`boolean` `canSaveDocument​(Object element)` Returns whether the document provided for the given element differs from its original state which would required that it be saved.
`void` `changed​(Object element)` Informs this document provider that the given element has been changed.
`void` `connect​(Object element)` Connects the given element to this document provider.
`void` `disconnect​(Object element)` Disconnects the given element from this document provider.
`IAnnotationModel` `getAnnotationModel​(Object element)` Returns the annotation model for the given element.
`IContentType` `getContentType​(Object element)` Returns the content type of for the given element or `null` if none could be determined.
`String` `getDefaultEncoding()` Returns the default character encoding used by this provider.
`IDocument` `getDocument​(Object element)` Returns the document for the given element.
`String` `getEncoding​(Object element)` Returns the character encoding for the given element, or `null` if the element is not managed by this provider.
`long` `getModificationStamp​(Object element)` Returns the modification stamp of the given element.
`IProgressMonitor` `getProgressMonitor()` Returns this providers progress monitor.
`IStatus` `getStatus​(Object element)` Returns the status of the given element.
`long` `getSynchronizationStamp​(Object element)` Returns the time stamp of the last synchronization of the given element and its provided document.
`boolean` `isDeleted​(Object element)` Returns whether the given element has been deleted.
`boolean` `isModifiable​(Object element)` Returns whether the document provider thinks that the given element can persistently be modified.
`boolean` `isNotSynchronizedException​(Object element, CoreException ex)` Tells whether the given core exception is exactly the exception which is thrown for a non-synchronized element.
`boolean` `isReadOnly​(Object element)` Returns whether the document provider thinks that the given element is read-only.
`boolean` `isStateValidated​(Object element)` Returns whether the state of the given element has been validated.
`boolean` `isSynchronized​(Object element)` Returns whether the information provided for the given element is in sync with the element.
`boolean` `mustSaveDocument​(Object element)` Returns whether the document provided for the given element must be saved.
`void` `removeElementStateListener​(IElementStateListener listener)` Removes the given element state listener from this document provider.
`void` `resetDocument​(Object element)` Resets the given element's document to its last saved state.
`void` `saveDocument​(IProgressMonitor monitor, Object element, IDocument document, boolean overwrite)` Saves the given document provided for the given element.
`void` `setCanSaveDocument​(Object element)` Marks the document managed for the given element as savable.
`void` `setEncoding​(Object element, String encoding)` Sets the encoding for the given element.
`void` `setParentProvider​(IDocumentProvider parentProvider)` Sets the parent document provider.
`void` `setProgressMonitor​(IProgressMonitor progressMonitor)` Sets this providers progress monitor.
`void` `synchronize​(Object element)` Synchronizes the document provided for the given element with the given element.
`void` `updateStateCache​(Object element)` Updates the state cache for the given element.
`void` `validateState​(Object element, Object computationContext)` Validates the state of the given element.

### Methods inherited from class java.lang.Object

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

### Constructor Detail

#### ForwardingDocumentProvider

    public ForwardingDocumentProvider​(String partitioning,
                                      IDocumentSetupParticipant documentSetupParticipant,
                                      IDocumentProvider parentProvider)

Creates a new forwarding document provider with a fixed parent document provider. Calling `setParentProvider(IDocumentProvider)` does not have any effect on this object.

Parameters:
  `partitioning` - the partitioning
  `documentSetupParticipant` - the document setup participant
  `parentProvider` - the parent document provider

#### ForwardingDocumentProvider

    public ForwardingDocumentProvider​(String partitioning,
                                      IDocumentSetupParticipant documentSetupParticipant)

Creates a new forwarding document provider with a dynamically changeable parent provider. Forwarding document providers created with that method are not allowed to be shared by multiple editors.

Parameters:
  `partitioning` - the partitioning
  `documentSetupParticipant` - the document setup participant

### Method Detail

#### setParentProvider

    public void setParentProvider​(IDocumentProvider parentProvider)

Sets the parent document provider. This method has only an effect if the forwarding document provider has accordingly be created.

Parameters:
  `parentProvider` - the new parent document provider

#### connect

    public void connect​(Object element)
                 throws CoreException

Description copied from interface: `IDocumentProvider`
Connects the given element to this document provider. This tells the provider that caller of this method is interested to work with the document provided for the given domain model element. By counting the invocations of this method and `disconnect(Object)` this provider can assume to know the correct number of clients working with the document provided for that domain model element.

The given element must not be `null`.

Specified by:
  `connect` in interface `IDocumentProvider`
Parameters:
  `element` - the element
Throws:
  `CoreException` - if the textual representation or the annotation model of the element could not be created

#### disconnect

    public void disconnect​(Object element)

Description copied from interface: `IDocumentProvider`
Disconnects the given element from this document provider. This tells the provider that the caller of this method is no longer interested in working with the document provided for the given domain model element. By counting the invocations of `connect(Object)` and of this method this provider can assume to know the correct number of clients working with the document provided for that domain model element.

The given element must not be `null`.

Specified by:
  `disconnect` in interface `IDocumentProvider`
Parameters:
  `element` - the element

#### getDocument

    public IDocument getDocument​(Object element)

Description copied from interface: `IDocumentProvider`
Returns the document for the given element. Usually the document contains a textual presentation of the content of the element, or is the element itself.

Specified by:
  `getDocument` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`
Returns:
  the document, or `null` if none

#### resetDocument

    public void resetDocument​(Object element)
                       throws CoreException

Description copied from interface: `IDocumentProvider`
Resets the given element's document to its last saved state. Element state listeners are notified both before (`elementContentAboutToBeReplaced`) and after (`elementContentReplaced`) the content is changed.

Specified by:
  `resetDocument` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`
Throws:
  `CoreException` - if document could not be reset for the given element

#### saveDocument

    public void saveDocument​(IProgressMonitor monitor,
                             Object element,
                             IDocument document,
                             boolean overwrite)
                      throws CoreException

Description copied from interface: `IDocumentProvider`
Saves the given document provided for the given element.

Specified by:
  `saveDocument` in interface `IDocumentProvider`
Parameters:
  `monitor` - a progress monitor to report progress and request cancelation
  `element` - the element, or `null`
  `document` - the document
  `overwrite` - indicates whether overwrite should be performed while saving the given element if necessary
Throws:
  `CoreException` - if document could not be stored to the given element

#### getModificationStamp

    public long getModificationStamp​(Object element)

Description copied from interface: `IDocumentProvider`
Returns the modification stamp of the given element.

Specified by:
  `getModificationStamp` in interface `IDocumentProvider`
Parameters:
  `element` - the element
Returns:
  the modification stamp of the given element

#### getSynchronizationStamp

    public long getSynchronizationStamp​(Object element)

Description copied from interface: `IDocumentProvider`
Returns the time stamp of the last synchronization of the given element and its provided document.

Specified by:
  `getSynchronizationStamp` in interface `IDocumentProvider`
Parameters:
  `element` - the element
Returns:
  the synchronization stamp of the given element

#### isDeleted

    public boolean isDeleted​(Object element)

Description copied from interface: `IDocumentProvider`
Returns whether the given element has been deleted.

Specified by:
  `isDeleted` in interface `IDocumentProvider`
Parameters:
  `element` - the element
Returns:
  `true` if the element has been deleted

#### mustSaveDocument

    public boolean mustSaveDocument​(Object element)

Description copied from interface: `IDocumentProvider`
Returns whether the document provided for the given element must be saved.

Specified by:
  `mustSaveDocument` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`
Returns:
  `true` if the document must be saved, and `false` otherwise (including the element is `null`)

#### canSaveDocument

    public boolean canSaveDocument​(Object element)

Description copied from interface: `IDocumentProvider`
Returns whether the document provided for the given element differs from its original state which would required that it be saved.

Specified by:
  `canSaveDocument` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`
Returns:
  `true` if the document can be saved, and `false` otherwise (including the element is `null`)

#### getAnnotationModel

    public IAnnotationModel getAnnotationModel​(Object element)

Description copied from interface: `IDocumentProvider`
Returns the annotation model for the given element.

Specified by:
  `getAnnotationModel` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`
Returns:
  the annotation model, or `null` if none

#### aboutToChange

    public void aboutToChange​(Object element)

Description copied from interface: `IDocumentProvider`
Informs this document provider about upcoming changes of the given element. The changes might cause change notifications specific for the type of the given element. If this provider manages a document for the given element, the document provider must not change the document because of the notifications received after `aboutToChange` has been and before `changed` is called. In this case, it is assumed that the document is already up to date, e.g., a save operation is a typical case.

The concrete nature of the change notification depends on the concrete type of the given element. If the element is, e.g., an `IResource` the notification is a resource delta.

Specified by:
  `aboutToChange` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`

#### changed

    public void changed​(Object element)

Description copied from interface: `IDocumentProvider`
Informs this document provider that the given element has been changed. All notifications have been sent out. If this provider manages a document for the given element, the document provider must from now on change the document on the receipt of change notifications. The concrete nature of the change notification depends on the concrete type of the given element. If the element is, e.g., an `IResource` the notification is a resource delta.

Specified by:
  `changed` in interface `IDocumentProvider`
Parameters:
  `element` - the element, or `null`

#### addElementStateListener

    public void addElementStateListener​(IElementStateListener listener)

Description copied from interface: `IDocumentProvider`
Adds the given element state listener to this document provider. Has no effect if an identical listener is already registered.

Specified by:
  `addElementStateListener` in interface `IDocumentProvider`
Parameters:
  `listener` - the listener

#### removeElementStateListener

    public void removeElementStateListener​(IElementStateListener listener)

Description copied from interface: `IDocumentProvider`
Removes the given element state listener from this document provider. Has no effect if an identical listener is not registered.

Specified by:
  `removeElementStateListener` in interface `IDocumentProvider`
Parameters:
  `listener` - the listener

#### isReadOnly

    public boolean isReadOnly​(Object element)

Description copied from interface: `IDocumentProviderExtension`
Returns whether the document provider thinks that the given element is read-only. If this method returns `true`, `saveDocument` could fail. This method does not say anything about the document constructed from the given element. If the given element is not connected to this document provider, the return value is undefined. Document providers are allowed to use a cache to answer this question, i.e. there can be a difference between the "real" state of the element and the return value.

Specified by:
  `isReadOnly` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
Returns:
  `true` if the given element is read-only, `false` otherwise

#### isModifiable

    public boolean isModifiable​(Object element)

Description copied from interface: `IDocumentProviderExtension`
Returns whether the document provider thinks that the given element can persistently be modified. This is orthogonal to `isReadOnly` as read-only elements may be modifiable and writable elements may not be modifiable. If the given element is not connected to this document provider, the result is undefined. Document providers are allowed to use a cache to answer this question, i.e. there can be a difference between the "real" state of the element and the return value.

Specified by:
  `isModifiable` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
Returns:
  `true` if the given element is modifiable, `false` otherwise

#### validateState

    public void validateState​(Object element,
                              Object computationContext)
                       throws CoreException

Description copied from interface: `IDocumentProviderExtension`
Validates the state of the given element. This method may change the "real" state of the element. If using, it also updates the internal caches, so that this method may also change the results returned by `isReadOnly` and `isModifiable`. If the given element is not connected to this document provider, the effect is undefined.

Specified by:
  `validateState` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
  `computationContext` - the context in which the computation is performed, e.g., a SWT shell
Throws:
  `CoreException` - if validating fails

#### isStateValidated

    public boolean isStateValidated​(Object element)

Description copied from interface: `IDocumentProviderExtension`
Returns whether the state of the given element has been validated.

Specified by:
  `isStateValidated` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
Returns:
  `true` if the state has been validated

#### updateStateCache

    public void updateStateCache​(Object element)
                          throws CoreException

Description copied from interface: `IDocumentProviderExtension`
Updates the state cache for the given element. This method may change the result returned by `isReadOnly` and `isModifiable`. If the given element is not connected to this document provider, the effect is undefined.

Specified by:
  `updateStateCache` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
Throws:
  `CoreException` - if validating fails

#### setCanSaveDocument

    public void setCanSaveDocument​(Object element)

Description copied from interface: `IDocumentProviderExtension`
Marks the document managed for the given element as savable. I.e. `canBeSaved(element)` will return `true` afterwards.

Specified by:
  `setCanSaveDocument` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element

#### getStatus

    public IStatus getStatus​(Object element)

Description copied from interface: `IDocumentProviderExtension`
Returns the status of the given element.

Specified by:
  `getStatus` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
Returns:
  the status of the given element

#### synchronize

    public void synchronize​(Object element)
                     throws CoreException

Description copied from interface: `IDocumentProviderExtension`
Synchronizes the document provided for the given element with the given element. After that call `getSynchronizationTimeStamp` and `getModificationTimeStamp` return the same value.

Specified by:
  `synchronize` in interface `IDocumentProviderExtension`
Parameters:
  `element` - the element
Throws:
  `CoreException` - if the synchronization could not be performed

#### setProgressMonitor

    public void setProgressMonitor​(IProgressMonitor progressMonitor)

Description copied from interface: `IDocumentProviderExtension2`
Sets this providers progress monitor.

Specified by:
  `setProgressMonitor` in interface `IDocumentProviderExtension2`
Parameters:
  `progressMonitor` - the progress monitor

#### getProgressMonitor

    public IProgressMonitor getProgressMonitor()

Description copied from interface: `IDocumentProviderExtension2`
Returns this providers progress monitor.

Specified by:
  `getProgressMonitor` in interface `IDocumentProviderExtension2`
Returns:
  IProgressMonitor

#### isSynchronized

    public boolean isSynchronized​(Object element)

Description copied from interface: `IDocumentProviderExtension3`
Returns whether the information provided for the given element is in sync with the element.

Specified by:
  `isSynchronized` in interface `IDocumentProviderExtension3`
Parameters:
  `element` - the element
Returns:
  `true` if the information is in sync with the element, `false` otherwise

#### isNotSynchronizedException

    public boolean isNotSynchronizedException​(Object element,
                                              CoreException ex)

Description copied from interface: `IDocumentProviderExtension5`
Tells whether the given core exception is exactly the exception which is thrown for a non-synchronized element.

Specified by:
  `isNotSynchronizedException` in interface `IDocumentProviderExtension5`
Parameters:
  `element` - the element
  `ex` - the core exception
Returns:
  `true` iff the given core exception is exactly the exception which is thrown for a non-synchronized element

#### getContentType

    public IContentType getContentType​(Object element)
                                throws CoreException

Description copied from interface: `IDocumentProviderExtension4`
Returns the content type of for the given element or `null` if none could be determined. If the element's document can be saved, the returned content type is determined by the document's current content.

Specified by:
  `getContentType` in interface `IDocumentProviderExtension4`
Parameters:
  `element` - the element
Returns:
  the content type or `null`
Throws:
  `CoreException` - if reading or accessing the underlying store fails

#### getDefaultEncoding

    public String getDefaultEncoding()

Description copied from interface: `IStorageDocumentProvider`
Returns the default character encoding used by this provider.

Specified by:
  `getDefaultEncoding` in interface `IStorageDocumentProvider`
Returns:
  the default character encoding used by this provider

#### getEncoding

    public String getEncoding​(Object element)

Description copied from interface: `IStorageDocumentProvider`
Returns the character encoding for the given element, or `null` if the element is not managed by this provider.

Specified by:
  `getEncoding` in interface `IStorageDocumentProvider`
Parameters:
  `element` - the element
Returns:
  the encoding for the given element

#### setEncoding

    public void setEncoding​(Object element,
                            String encoding)

Description copied from interface: `IStorageDocumentProvider`
Sets the encoding for the given element. If `encoding` is `null` the workbench's character encoding should be used.

Specified by:
  `setEncoding` in interface `IStorageDocumentProvider`
Parameters:
  `element` - the element
  `encoding` - the encoding to be used