Package org.eclipse.compare.contentmergeviewer

Class ContentMergeViewer

java.lang.Object
org.eclipse.jface.viewers.Viewer
org.eclipse.jface.viewers.ContentViewer
org.eclipse.compare.contentmergeviewer.ContentMergeViewer
All Implemented Interfaces:
IFlushable, IFlushable2, IPropertyChangeNotifier, IInputProvider, IInputSelectionProvider, ISelectionProvider
Direct Known Subclasses:
ImageMergeViewer, TextMergeViewer
public abstract class ContentMergeViewer extends ContentViewer implements IPropertyChangeNotifier, IFlushable, IFlushable2
An abstract compare and merge viewer with two side-by-side content areas and an optional content area for the ancestor. The implementation makes no assumptions about the content type.

ContentMergeViewer

  • implements the overall layout and defines hooks so that subclasses can easily provide an implementation for a specific content type,
  • implements the UI for making the areas resizable,
  • has an action for controlling whether the ancestor area is visible or not,
  • has actions for copying one side of the input to the other side,
  • tracks the dirty state of the left and right sides and send out notification on state changes.

A ContentMergeViewer accesses its model by means of a content provider which must implement the IMergeViewerContentProvider interface.

Clients may wish to use the standard concrete subclass TextMergeViewer, or define their own subclass.

See Also:

  • Constructor Details

    • ContentMergeViewer

      protected ContentMergeViewer(int style, ResourceBundle bundle, CompareConfiguration cc)
      Creates a new content merge viewer and initializes with a resource bundle and a configuration.
      Parameters:
      style - SWT style bits
      bundle - the resource bundle
      cc - the configuration object

  • Method Details

    • getTitle

      public String getTitle()
      Returns the viewer's name.
      Returns:
      the viewer's name

    • createControls

      protected abstract void createControls(Composite composite)
      Creates the SWT controls for the ancestor, left, and right content areas of this compare viewer. Implementations typically hold onto the controls so that they can be initialized with the input objects in method updateContent.
      Parameters:
      composite - the container for the three areas

    • handleResizeAncestor

      protected abstract void handleResizeAncestor(int x, int y, int width, int height)
      Lays out the ancestor area of the compare viewer. It is called whenever the viewer is resized or when the sashes between the areas are moved to adjust the size of the areas.
      Parameters:
      x - the horizontal position of the ancestor area within its container
      y - the vertical position of the ancestor area within its container
      width - the width of the ancestor area
      height - the height of the ancestor area

    • handleResizeLeftRight

      protected abstract void handleResizeLeftRight(int x, int y, int leftWidth, int centerWidth, int rightWidth, int height)
      Lays out the left and right areas of the compare viewer. It is called whenever the viewer is resized or when the sashes between the areas are moved to adjust the size of the areas.
      Parameters:
      x - the horizontal position of the left area within its container
      y - the vertical position of the left and right area within its container
      leftWidth - the width of the left area
      centerWidth - the width of the gap between the left and right areas
      rightWidth - the width of the right area
      height - the height of the left and right areas

    • createToolItems

      protected void createToolItems(ToolBarManager toolBarManager)
      Contributes items to the given ToolBarManager. It is called when this viewer is installed in its container and if the container has a ToolBarManager. The ContentMergeViewer implementation of this method does nothing. Subclasses may reimplement.
      Parameters:
      toolBarManager - the toolbar manager to contribute to

    • updateContent

      protected abstract void updateContent(Object ancestor, Object left, Object right)
      Initializes the controls of the three content areas with the given input objects.
      Parameters:
      ancestor - the input for the ancestor area
      left - the input for the left area
      right - the input for the right area

    • copy

      protected abstract void copy(boolean leftToRight)
      Copies the content of one side to the other side. Called from the (internal) actions for copying the sides of the viewer's input object.
      Parameters:
      leftToRight - if true, the left side is copied to the right side; if false, the right side is copied to the left side

    • getContents

      protected abstract byte[] getContents(boolean left)
      Returns the byte contents of the left or right side. If the viewer has no editable content null can be returned.
      Parameters:
      left - if true, the byte contents of the left area is returned; if false, the byte contents of the right area
      Returns:
      the content as an array of bytes, or null

    • getResourceBundle

      protected ResourceBundle getResourceBundle()
      Returns the resource bundle of this viewer.
      Returns:
      the resource bundle

    • getCompareConfiguration

      protected CompareConfiguration getCompareConfiguration()
      Returns the compare configuration of this viewer.
      Returns:
      the compare configuration, never null

    • setContentProvider

      public void setContentProvider(IContentProvider contentProvider)
      The ContentMergeViewer implementation of this ContentViewer method checks to ensure that the content provider is an IMergeViewerContentProvider.
      Overrides:
      setContentProvider in class ContentViewer
      Parameters:
      contentProvider - the content provider to set. Must implement IMergeViewerContentProvider.
      See Also:

    • getSelection

      public ISelection getSelection()
      The ContentMergeViewer implementation of this Viewer method returns the empty selection. Subclasses may override.
      Specified by:
      getSelection in interface ISelectionProvider
      Specified by:
      getSelection in class Viewer
      Returns:
      empty selection.

    • setSelection

      public void setSelection(ISelection selection, boolean reveal)
      The ContentMergeViewer implementation of this Viewer method does nothing. Subclasses may reimplement.
      Specified by:
      setSelection in class Viewer
      Parameters:
      selection - the new selection
      reveal - true if the selection is to be made visible, and false otherwise
      See Also:

    • handlePropertyChangeEvent

      protected void handlePropertyChangeEvent(PropertyChangeEvent event)
      Callback that is invoked when a property in the compare configuration (getCompareConfiguration() changes.
      Parameters:
      event - the property change event
      Since:
      3.3

    • isThreeWay

      protected boolean isThreeWay()
      Return whether the input is a three-way comparison.
      Returns:
      whether the input is a three-way comparison
      Since:
      3.3

    • inputChanged

      protected final void inputChanged(Object input, Object oldInput)
      Internal hook method called when the input to this viewer is initially set or subsequently changed.

      The ContentMergeViewer implementation of this Viewer method tries to save the old input by calling doSave(...) and then calls internalRefresh(...).

      Overrides:
      inputChanged in class Viewer
      Parameters:
      input - the new input of this viewer, or null if there is no new input
      oldInput - the old input element, or null if there was previously no input

    • doSave

      protected boolean doSave(Object newInput, Object oldInput)
      This method is called from the Viewer method inputChanged to save any unsaved changes of the old input.

      The ContentMergeViewer implementation of this method calls saveContent(...). If confirmation has been turned on with setConfirmSave(true), a confirmation alert is posted before saving.

      Clients can override this method and are free to decide whether they want to call the inherited method.
      Parameters:
      newInput - the new input of this viewer, or null if there is no new input
      oldInput - the old input element, or null if there was previously no input
      Returns:
      true if saving was successful, or if the user didn't want to save (by pressing 'NO' in the confirmation dialog).
      Since:
      2.0

    • setConfirmSave

      public void setConfirmSave(boolean enable)
      Controls whether doSave(Object, Object) asks for confirmation before saving the old input with saveContent(Object).
      Parameters:
      enable - a value of true enables confirmation
      Since:
      2.0

    • refresh

      public void refresh()
      Description copied from class: Viewer
      Refreshes this viewer completely with information freshly obtained from this viewer's model.
      Specified by:
      refresh in class Viewer

    • hookControl

      protected void hookControl(Control control)
      Description copied from class: ContentViewer
      Adds event listener hooks to the given control.

      All subclasses must call this method when their control is first established.

      The ContentViewer implementation of this method hooks dispose events for the given control. Subclasses may override if they need to add other control hooks; however, super.hookControl must be invoked.

      Overrides:
      hookControl in class ContentViewer
      Parameters:
      control - the control

    • buildControl

      protected final Control buildControl(Composite parent)
      Builds the SWT controls for the three areas of a compare/merge viewer.

      Calls the hooks createControls and createToolItems to let subclasses build the specific content areas and to add items to an enclosing toolbar.

      This method must only be called in the constructor of subclasses.

      Parameters:
      parent - the parent control
      Returns:
      the new control

    • getToolBarManager

      protected IToolBarManager getToolBarManager(Composite parent)
      Returns the toolbar manager for this viewer. Subclasses may extend this method and use either the toolbar manager provided by the inherited method by calling super.getToolBarManager(parent) or provide an alternate toolbar manager.
      Parameters:
      parent - a Composite or null
      Returns:
      a IToolBarManager
      Since:
      3.4

    • handleSetFocus

      protected boolean handleSetFocus()
      Callback that is invoked when the control of this merge viewer is given focus. This method should return true if a particular widget was given focus and false otherwise. By default, false is returned. Subclasses may override.
      Returns:
      whether particular widget was given focus
      Since:
      3.3

    • getCenterWidth

      protected int getCenterWidth()
      Return the desired width of the center control. This width is used to calculate the values used to layout the ancestor, left and right sides.
      Returns:
      the desired width of the center control
      Since:
      3.3
      See Also:

    • isAncestorVisible

      protected boolean isAncestorVisible()
      Return whether the ancestor pane is visible or not.
      Returns:
      whether the ancestor pane is visible or not
      Since:
      3.3

    • createCenterControl

      protected Control createCenterControl(Composite parent)
      Create the control that divides the left and right sides of the merge viewer.
      Parameters:
      parent - the parent composite
      Returns:
      the center control
      Since:
      3.3

    • getCenterControl

      protected Control getCenterControl()
      Return the center control that divides the left and right sides of the merge viewer. This method returns the control that was created by calling createCenterControl(Composite).
      Returns:
      the center control
      Since:
      3.3
      See Also:

    • getControl

      public Control getControl()
      Description copied from class: Viewer
      Returns the primary control associated with this viewer.
      Specified by:
      getControl in class Viewer
      Returns:
      the SWT control which displays this viewer's content

    • handleDispose

      protected void handleDispose(DisposeEvent event)
      Called on the viewer disposal. Unregisters from the compare configuration. Clients may extend if they have to do additional cleanup.
      Overrides:
      handleDispose in class ContentViewer
      Parameters:
      event - a dispose event
      See Also:

    • updateToolItems

      protected void updateToolItems()
      Updates the enabled state of the toolbar items.

      This method is called whenever the state of the items needs updating.

      Subclasses may extend this method, although this is generally not required.

    • updateHeader

      protected void updateHeader()
      Updates the headers of the three areas by querying the content provider for a name and image for the three sides of the input object.

      This method is called whenever the header must be updated.

      Subclasses may extend this method, although this is generally not required.

    • addPropertyChangeListener

      public void addPropertyChangeListener(IPropertyChangeListener listener)
      Description copied from interface: IPropertyChangeNotifier
      Adds a listener for property changes to this notifier. Has no effect if an identical listener is already registered.
      Specified by:
      addPropertyChangeListener in interface IPropertyChangeNotifier
      Parameters:
      listener - a property change listener

    • removePropertyChangeListener

      public void removePropertyChangeListener(IPropertyChangeListener listener)
      Description copied from interface: IPropertyChangeNotifier
      Removes the given content change listener from this notifier. Has no effect if the identical listener is not registered.
      Specified by:
      removePropertyChangeListener in interface IPropertyChangeNotifier
      Parameters:
      listener - a property change listener

    • setLeftDirty

      protected void setLeftDirty(boolean dirty)
      Sets the dirty state of the left side of this viewer. If the new value differs from the old all registered listener are notified with a PropertyChangeEvent with the property name CompareEditorInput.DIRTY_STATE.
      Parameters:
      dirty - the state of the left side dirty flag

    • setRightDirty

      protected void setRightDirty(boolean dirty)
      Sets the dirty state of the right side of this viewer. If the new value differs from the old all registered listener are notified with a PropertyChangeEvent with the property name CompareEditorInput.DIRTY_STATE.
      Parameters:
      dirty - the state of the right side dirty flag

    • save

      @Deprecated public void save(IProgressMonitor monitor) throws CoreException
      Deprecated.
      use IFlushable.flush(IProgressMonitor).
      Method from the old internal ISavable interface Save the viewers's content. Note: this method is for internal use only. Clients should not call this method.
      Parameters:
      monitor - a progress monitor
      Throws:
      CoreException - not thrown anymore

    • flush

      public final void flush(IProgressMonitor monitor)
      Flush any modifications made in the viewer into the compare input. This method calls flushContent(Object, IProgressMonitor) with the compare input of the viewer as the first parameter.
      Specified by:
      flush in interface IFlushable
      Parameters:
      monitor - a progress monitor
      Since:
      3.3
      See Also:

    • flushContent

      protected void flushContent(Object input, IProgressMonitor monitor)
      Flushes the modified content back to input elements via the content provider. The provided input may be the current input of the viewer or it may be the previous input (i.e. this method may be called to flush modified content during an input change).
      Parameters:
      input - the compare input
      monitor - a progress monitor or null if the method was call from a place where a progress monitor was not available.
      Since:
      3.3

    • flushLeft

      public void flushLeft(IProgressMonitor monitor)
      Specified by:
      flushLeft in interface IFlushable2
      Parameters:
      monitor - The progress monitor to report progress.
      Restriction:
      This method is not intended to be referenced by clients.

    • flushRight

      public void flushRight(IProgressMonitor monitor)
      Specified by:
      flushRight in interface IFlushable2
      Parameters:
      monitor - The progress monitor to report progress.
      Restriction:
      This method is not intended to be referenced by clients.

    • isRightDirty

      protected boolean isRightDirty()
      Return the dirty state of the right side of this viewer.
      Returns:
      the dirty state of the right side of this viewer
      Since:
      3.3

    • internalIsRightDirty

      public boolean internalIsRightDirty()
      Returns:
      the dirty state of the right side of this viewer
      Since:
      3.7
      Restriction:
      This method is not intended to be referenced by clients.

    • isLeftDirty

      protected boolean isLeftDirty()
      Return the dirty state of the left side of this viewer.
      Returns:
      the dirty state of the left side of this viewer
      Since:
      3.3

    • internalIsLeftDirty

      public boolean internalIsLeftDirty()
      Returns:
      the dirty state of the left side of this viewer
      Since:
      3.7
      Restriction:
      This method is not intended to be referenced by clients.

    • handleCompareInputChange

      protected void handleCompareInputChange()
      Handle a change to the given input reported from an ICompareInputChangeListener. This class registers a listener with its input and reports any change events through this method. By default, this method prompts for any unsaved changes and then refreshes the viewer. Subclasses may override.
      Since:
      3.3

    • isLeftEditable

      protected boolean isLeftEditable()
      If the inputs are mirrored, this asks the right model value.
      Returns:
      true if the left viewer is editable
      Since:
      3.7

    • isRightEditable

      protected boolean isRightEditable()
      If the inputs are mirrored, this asks the left model value.
      Returns:
      true if the right viewer is editable
      Since:
      3.7