org.eclipse.jface.bindings

Class BindingManager

java.lang.Object

org.eclipse.core.commands.common.EventManager

org.eclipse.core.commands.common.HandleObjectManager

org.eclipse.jface.bindings.BindingManager

All Implemented Interfaces:

IContextManagerListener, ISchemeListener

public final class BindingManager
extends HandleObjectManager
implements IContextManagerListener, ISchemeListener

A central repository for bindings -- both in the defined and undefined states. Schemes and bindings can be created and retrieved using this manager. It is possible to listen to changes in the collection of schemes and bindings by adding a listener to the manager.

The binding manager is very sensitive to performance. Misusing the manager can render an application unenjoyable to use. As such, each of the public methods states the current run-time performance. In future releases, it is guaranteed that the method will run in at least the stated time constraint -- though it might get faster. Where possible, we have also tried to be memory efficient.

Since:

3.1

Field Summary

Fields

Modifier and Type	Field and Description
static boolean	DEBUG This flag can be set to true if the binding manager should print information to System.out when certain boundary conditions occur.

Fields inherited from class org.eclipse.core.commands.common.HandleObjectManager

definedHandleObjects, handleObjectsById

Constructor Summary

Constructors

Constructor and Description
BindingManager(ContextManager contextManager, CommandManager commandManager) Constructs a new instance of BindingManager.

Method Summary

Modifier and Type	Method and Description
void	addBinding(Binding binding) Adds a single new binding to the existing array of bindings.
void	addBindingManagerListener(IBindingManagerListener listener) Adds a listener to this binding manager.
void	contextManagerChanged(ContextManagerEvent contextManagerEvent) Notifies this manager that the context manager has changed.
Map	getActiveBindingsDisregardingContext() Computes the bindings for the current state of the application, but disregarding the current contexts.
Collection	getActiveBindingsDisregardingContextFlat() Computes the bindings for the current state of the application, but disregarding the current contexts.
TriggerSequence[]	getActiveBindingsDisregardingContextFor(ParameterizedCommand parameterizedCommand) Returns the active bindings for a particular command identifier, but discounting the current contexts.
TriggerSequence[]	getActiveBindingsFor(ParameterizedCommand parameterizedCommand) Returns the active bindings for a particular command identifier.
TriggerSequence[]	getActiveBindingsFor(String commandId) Returns the active bindings for a particular command identifier.
Scheme	getActiveScheme() Gets the currently active scheme.
TriggerSequence	getBestActiveBindingFor(ParameterizedCommand command)
TriggerSequence	getBestActiveBindingFor(String commandId) Gets the best active binding for a command.
String	getBestActiveBindingFormattedFor(String commandId) Gets the formatted string representing the best active binding for a command.
Binding[]	getBindings() Returns the set of all bindings managed by this class.
Collection	getConflictsFor(TriggerSequence sequence) Provides the current conflicts in the keybindings for the given TriggerSequence as a Collection of Binding
Map	getCurrentConflicts() Provides the current conflicts in the bindings as a Map The key will be TriggerSequence and the value will be the Collection of Binding
Scheme[]	getDefinedSchemes() Returns the array of schemes that are defined.
String	getLocale() Returns the active locale for this binding manager.
Map	getPartialMatches(TriggerSequence trigger) Returns all of the possible bindings that start with the given trigger (but are not equal to the given trigger).
Binding	getPerfectMatch(TriggerSequence trigger) Returns the command identifier for the active binding matching this trigger, if any.
String	getPlatform() Returns the active platform for this binding manager.
Scheme	getScheme(String schemeId) Gets the scheme with the given identifier.
boolean	isPartialMatch(TriggerSequence trigger) Returns whether the given trigger sequence is a partial match for the given sequence.
boolean	isPerfectMatch(TriggerSequence trigger) Returns whether the given trigger sequence is a perfect match for the given sequence.
void	removeBinding(Binding binding) Remove the specific binding by identity.
void	removeBindingManagerListener(IBindingManagerListener listener) Removes a listener from this binding manager.
void	removeBindings(TriggerSequence sequence, String schemeId, String contextId, String locale, String platform, String windowManager, int type) Removes any binding that matches the given values -- regardless of command identifier.
void	schemeChanged(SchemeEvent schemeEvent) Notifies this manager that a scheme has changed.
void	setActiveScheme(Scheme scheme) Selects one of the schemes as the active scheme.
void	setBindings(Binding[] bindings) Changes the set of bindings for this binding manager.
void	setLocale(String locale) Changes the locale for this binding manager.
void	setPlatform(String platform) Changes the platform for this binding manager.

Methods inherited from class org.eclipse.core.commands.common.HandleObjectManager

checkId, getDefinedHandleObjectIds

Methods inherited from class org.eclipse.core.commands.common.EventManager

addListenerObject, clearListeners, getListeners, isListenerAttached, removeListenerObject

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

public static boolean DEBUG

This flag can be set to true if the binding manager should print information to System.out when certain boundary conditions occur.

Constructor Detail

BindingManager

public BindingManager(ContextManager contextManager,
                      CommandManager commandManager)

Constructs a new instance of BindingManager.

This method completes in amortized constant time (O(1)).

Parameters:

contextManager - The context manager that will support this binding manager. This value must not be null.

commandManager - The command manager that will support this binding manager. This value must not be null.

Method Detail

addBinding

public void addBinding(Binding binding)

Adds a single new binding to the existing array of bindings. If the array is currently null, then a new array is created and this binding is added to it. This method does not detect duplicates.

This method completes in amortized O(1).

Parameters:

binding - The binding to be added; must not be null.

addBindingManagerListener

public void addBindingManagerListener(IBindingManagerListener listener)

Adds a listener to this binding manager. The listener will be notified when the set of defined schemes or bindings changes. This can be used to track the global appearance and disappearance of bindings.

This method completes in amortized constant time (O(1)).

Parameters:

listener - The listener to attach; must not be null.

contextManagerChanged

public void contextManagerChanged(ContextManagerEvent contextManagerEvent)

Notifies this manager that the context manager has changed. This method is intended for internal use only.

This method completes in O(1).

Specified by:

contextManagerChanged in interface IContextManagerListener

Parameters:

contextManagerEvent - the context manager event. Guaranteed not to be null.

getActiveBindingsDisregardingContext

public Map getActiveBindingsDisregardingContext()

Computes the bindings for the current state of the application, but disregarding the current contexts. This can be useful when trying to display all the possible bindings.

This method completes in O(n), where n is the number of bindings.

Returns:

A map of trigger (TriggerSequence) to bindings ( Collection containing Binding). This map may be empty, but it is never null.

getActiveBindingsDisregardingContextFlat

public Collection getActiveBindingsDisregardingContextFlat()

Computes the bindings for the current state of the application, but disregarding the current contexts. This can be useful when trying to display all the possible bindings.

This method completes in O(n), where n is the number of bindings.

Returns:

All of the active bindings (Binding), not sorted in any fashion. This collection may be empty, but it is never null.

getActiveBindingsDisregardingContextFor

public TriggerSequence[] getActiveBindingsDisregardingContextFor(ParameterizedCommand parameterizedCommand)

Returns the active bindings for a particular command identifier, but discounting the current contexts. This method operates in O(n) time over the number of bindings.

This method completes in O(1). If the active bindings are not yet computed, then this completes in O(nn), where n is the number of bindings.

Parameters:

parameterizedCommand - The fully-parameterized command whose bindings are requested. This argument may be null.

Returns:

The array of active triggers (TriggerSequence) for a particular command identifier. This value is guaranteed to never be null, but it may be empty.

Since:

3.2

getActiveBindingsFor

public TriggerSequence[] getActiveBindingsFor(ParameterizedCommand parameterizedCommand)

Returns the active bindings for a particular command identifier. This method operates in O(n) time over the number of bindings.

This method completes in O(1). If the active bindings are not yet computed, then this completes in O(nn), where n is the number of bindings.

Parameters:

parameterizedCommand - The fully-parameterized command whose bindings are requested. This argument may be null.

Returns:

The array of active triggers (TriggerSequence) for a particular command identifier. This value is guaranteed to never be null, but it may be empty.

getActiveBindingsFor

public TriggerSequence[] getActiveBindingsFor(String commandId)

Returns the active bindings for a particular command identifier. This method operates in O(n) time over the number of bindings.

This method completes in O(1). If the active bindings are not yet computed, then this completes in O(nn), where n is the number of bindings.

Parameters:

commandId - The identifier of the command whose bindings are requested. This argument may be null. It is assumed that the command has no parameters.

Returns:

The array of active triggers (TriggerSequence) for a particular command identifier. This value is guaranteed not to be null, but it may be empty.

getActiveScheme

public Scheme getActiveScheme()

Gets the currently active scheme.

This method completes in O(1).

Returns:

The active scheme; may be null if there is no active scheme. If a scheme is returned, it is guaranteed to be defined.

getBestActiveBindingFor

public TriggerSequence getBestActiveBindingFor(String commandId)

Gets the best active binding for a command. The best binding is the one that would be most appropriate to show in a menu. Bindings which belong to a child scheme are given preference over those in a parent scheme. Bindings which belong to a particular locale or platform are given preference over those that do not. The rest of the calculaton is based most on various concepts of "length", as well as giving some modifier keys preference (e.g., Alt is less likely to appear than Ctrl).

Parameters:

commandId - The identifier of the command for which the best active binding should be retrieved; must not be null.

Returns:

The trigger sequence for the best binding; may be null if no bindings are active for the given command.

Since:

3.2

getBestActiveBindingFor

public TriggerSequence getBestActiveBindingFor(ParameterizedCommand command)

Parameters:

command -

Returns:

a trigger sequence, or null

Since:

3.4

getBestActiveBindingFormattedFor

public String getBestActiveBindingFormattedFor(String commandId)

Gets the formatted string representing the best active binding for a command. The best binding is the one that would be most appropriate to show in a menu. Bindings which belong to a child scheme are given preference over those in a parent scheme. The rest of the calculaton is based most on various concepts of "length", as well as giving some modifier keys preference (e.g., Alt is less likely to appear than Ctrl).

Parameters:

commandId - The identifier of the command for which the best active binding should be retrieved; must not be null.

Returns:

The formatted string for the best binding; may be null if no bindings are active for the given command.

Since:

3.2

getBindings

public Binding[] getBindings()

Returns the set of all bindings managed by this class.

This method completes in O(1).

Returns:

The array of all bindings. This value may be null and it may be empty.

getDefinedSchemes

public Scheme[] getDefinedSchemes()

Returns the array of schemes that are defined.

This method completes in O(1).

Returns:

The array of defined schemes; this value may be empty or null.

getLocale

public String getLocale()

Returns the active locale for this binding manager. The locale is in the same format as Locale.getDefault().toString().

This method completes in O(1).

Returns:

The active locale; never null.

getPartialMatches

public Map getPartialMatches(TriggerSequence trigger)

Returns all of the possible bindings that start with the given trigger (but are not equal to the given trigger).

This method completes in O(1). If the bindings aren't currently computed, then this completes in O(n), where n is the number of bindings.

Parameters:

trigger - The prefix to look for; must not be null.

Returns:

A map of triggers (TriggerSequence) to bindings (Binding). This map may be empty, but it is never null.

getPerfectMatch

public Binding getPerfectMatch(TriggerSequence trigger)

Returns the command identifier for the active binding matching this trigger, if any.

This method completes in O(1). If the bindings aren't currently computed, then this completes in O(n), where n is the number of bindings.

Parameters:

trigger - The trigger to match; may be null.

Returns:

The binding that matches, if any; null otherwise.

getPlatform

public String getPlatform()

Returns the active platform for this binding manager. The platform is in the same format as SWT.getPlatform().

This method completes in O(1).

Returns:

The active platform; never null.

getScheme

public Scheme getScheme(String schemeId)

Gets the scheme with the given identifier. If the scheme does not already exist, then a new (undefined) scheme is created with that identifier. This guarantees that schemes will remain unique.

This method completes in amortized O(1).

Parameters:

schemeId - The identifier for the scheme to retrieve; must not be null.

Returns:

A scheme with the given identifier.

isPartialMatch

public boolean isPartialMatch(TriggerSequence trigger)

Returns whether the given trigger sequence is a partial match for the given sequence.

This method completes in O(1). If the bindings aren't currently computed, then this completes in O(n), where n is the number of bindings.

Parameters:

trigger - The sequence which should be the prefix for some binding; should not be null.

Returns:

true if the trigger can be found in the active bindings; false otherwise.

isPerfectMatch

public boolean isPerfectMatch(TriggerSequence trigger)

Returns whether the given trigger sequence is a perfect match for the given sequence.

This method completes in O(1). If the bindings aren't currently computed, then this completes in O(n), where n is the number of bindings.

Parameters:

trigger - The sequence which should match exactly; should not be null.

Returns:

true if the trigger can be found in the active bindings; false otherwise.

removeBinding

public void removeBinding(Binding binding)

Remove the specific binding by identity. Does nothing if the binding is not in the manager.

This method completes in O(n), where n is the number of bindings.

Parameters:

binding - The binding to be removed; must not be null.

Since:

3.2

removeBindingManagerListener

public void removeBindingManagerListener(IBindingManagerListener listener)

Removes a listener from this binding manager.

This method completes in amortized O(1).

Parameters:

listener - The listener to be removed; must not be null.

removeBindings

public void removeBindings(TriggerSequence sequence,
                           String schemeId,
                           String contextId,
                           String locale,
                           String platform,
                           String windowManager,
                           int type)

Removes any binding that matches the given values -- regardless of command identifier.

This method completes in O(n), where n is the number of bindings.

Parameters:

sequence - The sequence to match; may be null.

schemeId - The scheme id to match; may be null.

contextId - The context id to match; may be null.

locale - The locale to match; may be null.

platform - The platform to match; may be null.

windowManager - The window manager to match; may be null. TODO Currently ignored.

type - The type to look for.

schemeChanged

public void schemeChanged(SchemeEvent schemeEvent)

Notifies this manager that a scheme has changed. This method is intended for internal use only.

This method calls out to listeners, and so the time it takes to complete is dependent on third-party code.

Specified by:

schemeChanged in interface ISchemeListener

Parameters:

schemeEvent - An event describing the change in the scheme.

getCurrentConflicts

public Map getCurrentConflicts()

Provides the current conflicts in the bindings as a Map The key will be TriggerSequence and the value will be the Collection of Binding

Returns:

Read-only Map of the current conflicts. If no conflicts, then return an empty map. Never null

Since:

3.5

getConflictsFor

public Collection getConflictsFor(TriggerSequence sequence)

Provides the current conflicts in the keybindings for the given TriggerSequence as a Collection of Binding

Parameters:

sequence - The sequence for which conflict info is required

Returns:

Collection of KeyBinding. If no conflicts, then returns a null

Since:

3.5

setActiveScheme

public void setActiveScheme(Scheme scheme)
                     throws NotDefinedException

Selects one of the schemes as the active scheme. This scheme must be defined.

This method completes in O(n), where n is the height of the context tree.

Parameters:

scheme - The scheme to become active; must not be null.

Throws:

NotDefinedException - If the given scheme is currently undefined.

setBindings

public void setBindings(Binding[] bindings)

Changes the set of bindings for this binding manager. Changing the set of bindings all at once ensures that: (1) duplicates are removed; and (2) avoids unnecessary intermediate computations. This method clears the existing bindings, but does not trigger a recomputation (other method calls are required to do that).

This method completes in O(n), where n is the number of bindings.

Parameters:

bindings - The new array of bindings; may be null. This set is copied into a local data structure.

setLocale

public void setLocale(String locale)

Changes the locale for this binding manager. The locale can be used to provide locale-specific bindings. If the locale is different than the current locale, this will force a recomputation of the bindings. The locale is in the same format as Locale.getDefault().toString().

This method completes in O(1).

Parameters:

locale - The new locale; must not be null.

See Also:

Locale.getDefault()

setPlatform

public void setPlatform(String platform)

Changes the platform for this binding manager. The platform can be used to provide platform-specific bindings. If the platform is different than the current platform, then this will force a recomputation of the bindings. The locale is in the same format as SWT.getPlatform().

This method completes in O(1).

Parameters:

platform - The new platform; must not be null.

See Also:

SWT.getPlatform(), Util.getWS()