org.eclipse.emf.edit.command
Class DragAndDropCommand

java.lang.Object
  org.eclipse.emf.common.command.AbstractCommand
      org.eclipse.emf.edit.command.DragAndDropCommand

All Implemented Interfaces:

Command, DragAndDropFeedback

Direct Known Subclasses:

DragAndDropOverrideCommand

public class DragAndDropCommand
extends AbstractCommand
implements DragAndDropFeedback

The drag and drop command logically acts upon an owner object onto which a collection of things is being dragged. The static create method delegates command creation to EditingDomain.createCommand, which may or may not result in the actual creation of an instance of this class.

The implementation of this class is high-level and generic; it ultimately delegates all behaviour to other types of command, and is typically undoable as a result.

Nested Class Summary

static class

DragAndDropCommand.Detail This class is used to encode the drag and drop arguments into an object that will be passed as the feature of a CommandParameter.

Nested classes/interfaces inherited from class org.eclipse.emf.common.command.AbstractCommand

AbstractCommand.NonDirtying

Field Summary

protected java.util.Collection<?>	collection This keeps track of the collection of dragged sources.
protected static java.lang.String	DESCRIPTION This caches the description.
protected EditingDomain	domain This keeps track of the domain in which this command is created.
protected Command	dragCommand This keeps track of the command that implements the drag side of the operation.
protected Command	dropCommand This keeps track of the command that implements the drop side of the operation.
protected int	feedback This keeps track of the feedback that will be returned by getFeedback().
protected boolean	isDragCommandExecuted This keeps track of whether execute has been called on the dragCommand.
protected static java.lang.String	LABEL This caches the label.
protected float	location This keeps track of the location of the drag and drop.
protected float	lowerLocationBound This keeps track of the lower range of locations in which the effect of this command remains unchanged.
protected int	operation This keeps track of the current operation that will be returned by getOperation().
protected int	operations This keeps track of the permitted operations.
protected boolean	optimize This controls whether or not to optimize the prepare().
protected java.lang.Object	optimizedDropCommandOwner This is to remember which owner to use for the drop command in the optimized mode.
protected java.lang.Object	owner This keeps track of the owner that is the target of the drag and drop.
protected float	upperLocationBound This keeps track of the upper range of locations in which the effect of this command remains unchanged.

Fields inherited from class org.eclipse.emf.common.command.AbstractCommand

description, isExecutable, isPrepared, label

Fields inherited from interface org.eclipse.emf.edit.command.DragAndDropFeedback

DROP_COPY, DROP_LINK, DROP_MOVE, DROP_NONE, FEEDBACK_INSERT_AFTER, FEEDBACK_INSERT_BEFORE, FEEDBACK_NONE, FEEDBACK_SELECT

Constructor Summary

DragAndDropCommand(EditingDomain domain, java.lang.Object owner, float location, int operations, int operation, java.util.Collection<?> collection)
This creates and instance in the given domain and for the given information.

DragAndDropCommand(EditingDomain domain, java.lang.Object owner, float location, int operations, int operation, java.util.Collection<?> collection, boolean optimize)

Method Summary

protected boolean	analyzeForNonContainment(Command command)
static Command	create(EditingDomain domain, java.lang.Object owner, float location, int operations, int operation, java.util.Collection<?> collection) This creates a command to perform a drag and drop operation upon the owner.
void	dispose() Called to indicate that the command will never be used again.
void	execute() Performs the command activity required for the effect.
java.util.Collection<?>	getAffectedObjects() Returns an empty list.
protected java.util.Collection<?>	getChildren(java.lang.Object object) This can be overridden to determine the children of an object; this implementation uses EditingDomain.getChildren(java.lang.Object).
java.util.Collection<?>	getCollection()
int	getFeedback() This returns one of the FEEDBACK_* values.
float	getLocation()
int	getOperation() This returns one of the DROP_* values.
int	getOperations()
java.lang.Object	getOwner()
protected java.lang.Object	getParent(java.lang.Object object) This can be overridden to determine the parent of an object; this implementation uses EditingDomain.getParent(java.lang.Object).
java.util.Collection<?>	getResult() Returns an empty list.
protected boolean	isCrossDomain()
protected boolean	isNonContainment(EStructuralFeature feature)
protected boolean	optimizedCanExecute()
protected boolean	prepare() This implementation of prepare is called again to implement validate.
protected boolean	prepareDropCopyInsert(java.lang.Object parent, java.util.Collection<?> children, int index) This attempts to prepare a drop copy insert operation.
protected boolean	prepareDropCopyOn() This attempts to prepare a drop copy on operation.
protected boolean	prepareDropInsert() This attempts to prepare a drop insert operation.
protected boolean	prepareDropLinkInsert(java.lang.Object parent, java.util.Collection<?> children, int index) This attempts to prepare a drop link insert operation.
protected boolean	prepareDropLinkOn() This attempts to prepare a drop link on operation.
protected boolean	prepareDropMoveInsert(java.lang.Object parent, java.util.Collection<?> children, int index) This attempts to prepare a drop move insert operation.
protected boolean	prepareDropMoveOn() This attempts to prepare a drop move on operation.
protected boolean	prepareDropOn() This attempts to prepare a drop on operation.
void	redo() Performs the command activity required to redo the effect after undoing the effect.
protected void	reset() This restores the command to its default initialized state, disposing an command that may have been contained.
java.lang.String	toString() This gives an abbreviated name using this object's own class' name, without package qualification, followed by a space separated list of field:value pairs.
void	undo() Throws a runtime exception.
boolean	validate(java.lang.Object owner, float location, int operations, int operation, java.util.Collection<?> collection) This is called by EditingDomainViewerDropAdapter to determine if the drag and drop operation is still enabled.

Methods inherited from class org.eclipse.emf.common.command.AbstractCommand

canExecute, canUndo, chain, getDescription, getLabel, setDescription, setLabel

Methods inherited from class java.lang.Object

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

Field Detail

LABEL

protected static final java.lang.String LABEL

This caches the label.

DESCRIPTION

protected static final java.lang.String DESCRIPTION

This caches the description.

domain

protected EditingDomain domain

This keeps track of the domain in which this command is created.

owner

protected java.lang.Object owner

This keeps track of the owner that is the target of the drag and drop.

location

protected float location

This keeps track of the location of the drag and drop.

lowerLocationBound

protected float lowerLocationBound

This keeps track of the lower range of locations in which the effect of this command remains unchanged.

upperLocationBound

protected float upperLocationBound

This keeps track of the upper range of locations in which the effect of this command remains unchanged.

operations

protected int operations

This keeps track of the permitted operations.

operation

protected int operation

This keeps track of the current operation that will be returned by getOperation().

feedback

protected int feedback

This keeps track of the feedback that will be returned by getFeedback().

collection

protected java.util.Collection<?> collection

This keeps track of the collection of dragged sources.

dragCommand

protected Command dragCommand

This keeps track of the command that implements the drag side of the operation.

isDragCommandExecuted

protected boolean isDragCommandExecuted

This keeps track of whether execute has been called on the dragCommand.

dropCommand

protected Command dropCommand

This keeps track of the command that implements the drop side of the operation.

optimize

protected boolean optimize

This controls whether or not to optimize the prepare().

optimizedDropCommandOwner

protected java.lang.Object optimizedDropCommandOwner

This is to remember which owner to use for the drop command in the optimized mode.

Constructor Detail

DragAndDropCommand

public DragAndDropCommand(EditingDomain domain,
                          java.lang.Object owner,
                          float location,
                          int operations,
                          int operation,
                          java.util.Collection<?> collection)

This creates and instance in the given domain and for the given information. The location should be in the range of 0.0 to 1.0, indicating the relative vertical location of the drag operation, where 0.0 is at the top and 1.0 is at the bottom. The operations is a bitwise mask of the DROP_* values. The operation is the desired operation as specified by a DROP_* value. And the collection contains the source objects being dragged.

DragAndDropCommand

public DragAndDropCommand(EditingDomain domain,
                          java.lang.Object owner,
                          float location,
                          int operations,
                          int operation,
                          java.util.Collection<?> collection,
                          boolean optimize)

Method Detail

create

public static Command create(EditingDomain domain,
                             java.lang.Object owner,
                             float location,
                             int operations,
                             int operation,
                             java.util.Collection<?> collection)

This creates a command to perform a drag and drop operation upon the owner. See DragAndDropCommand for a description of the arguments.

analyzeForNonContainment

protected boolean analyzeForNonContainment(Command command)

isNonContainment

protected boolean isNonContainment(EStructuralFeature feature)

getOwner

public java.lang.Object getOwner()

getLocation

public float getLocation()

getOperations

public int getOperations()

getCollection

public java.util.Collection<?> getCollection()

prepare

protected boolean prepare()

This implementation of prepare is called again to implement validate. The method reset() will have been called before doing so.

Overrides:

prepare in class AbstractCommand

Returns:

whether the command is executable.

getParent

protected java.lang.Object getParent(java.lang.Object object)

This can be overridden to determine the parent of an object; this implementation uses EditingDomain.getParent(java.lang.Object).

getChildren

protected java.util.Collection<?> getChildren(java.lang.Object object)

This can be overridden to determine the children of an object; this implementation uses EditingDomain.getChildren(java.lang.Object).

prepareDropInsert

protected boolean prepareDropInsert()

This attempts to prepare a drop insert operation.

prepareDropMoveInsert

protected boolean prepareDropMoveInsert(java.lang.Object parent,
                                        java.util.Collection<?> children,
                                        int index)

This attempts to prepare a drop move insert operation.

isCrossDomain

protected boolean isCrossDomain()

prepareDropCopyInsert

protected boolean prepareDropCopyInsert(java.lang.Object parent,
                                        java.util.Collection<?> children,
                                        int index)

This attempts to prepare a drop copy insert operation.

prepareDropLinkInsert

protected boolean prepareDropLinkInsert(java.lang.Object parent,
                                        java.util.Collection<?> children,
                                        int index)

This attempts to prepare a drop link insert operation.

prepareDropOn

protected boolean prepareDropOn()

This attempts to prepare a drop on operation.

prepareDropMoveOn

protected boolean prepareDropMoveOn()

This attempts to prepare a drop move on operation.

prepareDropCopyOn

protected boolean prepareDropCopyOn()

This attempts to prepare a drop copy on operation.

prepareDropLinkOn

protected boolean prepareDropLinkOn()

This attempts to prepare a drop link on operation.

optimizedCanExecute

protected boolean optimizedCanExecute()

reset

protected void reset()

This restores the command to its default initialized state, disposing an command that may have been contained.

validate

public boolean validate(java.lang.Object owner,
                        float location,
                        int operations,
                        int operation,
                        java.util.Collection<?> collection)

This is called by EditingDomainViewerDropAdapter to determine if the drag and drop operation is still enabled.

Specified by:

validate in interface DragAndDropFeedback

getFeedback

public int getFeedback()

Description copied from interface: DragAndDropFeedback

This returns one of the FEEDBACK_* values.

Specified by:

getFeedback in interface DragAndDropFeedback

getOperation

public int getOperation()

Description copied from interface: DragAndDropFeedback

This returns one of the DROP_* values.

Specified by:

getOperation in interface DragAndDropFeedback

execute

public void execute()

Description copied from interface: Command

Performs the command activity required for the effect. The effect of calling execute when canExecute returns false, or when canExecute hasn't been called, is undefined.

Specified by:

execute in interface Command

undo

public void undo()

Description copied from class: AbstractCommand

Throws a runtime exception.

Specified by:

undo in interface Command

Overrides:

undo in class AbstractCommand

redo

public void redo()

Description copied from interface: Command

Performs the command activity required to redo the effect after undoing the effect. The effect, if any, of calling redo before undo is called is undefined. Note that if you implement redo to call execute then any derived class will be restricted by that decision also.

Specified by:

redo in interface Command

dispose

public void dispose()

Description copied from interface: Command

Called to indicate that the command will never be used again. Calling any other method after this one has undefined results.

Specified by:

dispose in interface Command

Overrides:

dispose in class AbstractCommand

getResult

public java.util.Collection<?> getResult()

Description copied from class: AbstractCommand

Returns an empty list.

Specified by:

getResult in interface Command

Overrides:

getResult in class AbstractCommand

Returns:

an empty list.

getAffectedObjects

public java.util.Collection<?> getAffectedObjects()

Description copied from class: AbstractCommand

Returns an empty list.

Specified by:

getAffectedObjects in interface Command

Overrides:

getAffectedObjects in class AbstractCommand

Returns:

an empty list.

toString

public java.lang.String toString()

This gives an abbreviated name using this object's own class' name, without package qualification, followed by a space separated list of field:value pairs.

Overrides:

toString in class AbstractCommand

Returns:

string representation.