/*******************************************************************************
* Copyright (c) 2000, 2015 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.ui.activities;
import java.util.Set;
import org.eclipse.core.expressions.Expression;
/**
* An instance of this interface is an activity as defined by the extension
* point <code>org.eclipse.ui.activities</code>.
*
* <p>
* An instance of this interface can be obtained from an instance of
* <code>IActivityManager</code> for any identifier, whether or not an activity
* with that identifier is defined in the extension registry.
* </p>
*
* <p>
* The handle-based nature of this API allows it to work well with runtime
* plugin activation and deactivation, which can cause dynamic changes to the
* extension registry. A client may get an <code>IActivity</code> handle that
* is currently undefined ({@link #isDefined()} equals <code>false</code>) and
* listen for it to become defined.
* </p>
*
* <p>
* This interface is not intended to be extended or implemented by clients.
* </p>
*
* @since 3.0
* @see IActivityManager
* @noimplement This interface is not intended to be implemented by clients.
*/
public interface IActivity extends Comparable {
/**
* Registers an instance of <code>IActivityListener</code> to listen for
* changes to properties of this instance.
*
* @param activityListener
* the instance to register. Must not be <code>null</code>.
* If an attempt is made to register an instance which is
* already registered with this instance, no operation is
* performed.
*/
void addActivityListener(IActivityListener activityListener);
/**
* Returns the set of activity requirement bindings for this instance.
* <p>
* This method will return all activity requirement bindings for this
* instance, whether or not this instance is defined.
* </p>
* <p>
* Notification is sent to all registered listeners if this property
* changes.
* </p>
*
* @return the set of activity requirement bindings. This set may be empty,
* but is guaranteed not to be <code>null</code>. If this set is
* not empty, it is guaranteed to only contain instances of
* <code>IActivityRequirementBinding</code>.
* @see IActivityRequirementBinding
*/
Set getActivityRequirementBindings();
/**
* Returns the set of activity pattern bindings for this instance.
* <p>
* This method will return all activity pattern bindings for this instance,
* whether or not this instance is defined.
* </p>
* <p>
* Notification is sent to all registered listeners if this property
* changes.
* </p>
*
* @return the set of activity pattern bindings. This set may be empty, but
* is guaranteed not to be <code>null</code>. If this set is not
* empty, it is guaranteed to only contain instances of <code>IActivityPatternBinding</code>.
* @see IActivityPatternBinding
*/
Set getActivityPatternBindings();
/**
* Returns the identifier of this instance.
*
* @return the identifier of this instance. Guaranteed not to be <code>null</code>.
*/
String getId();
/**
* Returns the name of this instance suitable for display to the user.
* <p>
* Notification is sent to all registered listeners if this property
* changes.
* </p>
*
* @return the name of this instance. Guaranteed not to be <code>null</code>.
* @throws NotDefinedException
* if this instance is not defined.
*/
String getName() throws NotDefinedException;
/**
* Returns the description of this instance suitable for display to the user.
* <p>
* Notification is sent to all registered listeners if this property
* changes.
* </p>
*
* @return the description of this instance. Guaranteed not to be <code>null</code>.
* @throws NotDefinedException
* if this instance is not defined.
*/
String getDescription() throws NotDefinedException;
/**
* Returns whether or not this instance is defined. A defined activity
* may have a name, description and bindings (both pattern and relational).
* <p>
* Notification is sent to all registered listeners if this property
* changes.
* </p>
*
* @return <code>true</code>, iff this instance is defined.
*/
boolean isDefined();
/**
* Returns whether or not this instance is enabled.
* <p>
* Notification is sent to all registered listeners if this property
* changes.
* </p>
*
* @return <code>true</code>, iff this instance is enabled.
*/
boolean isEnabled();
/**
* Returns whether or not this instance should be enabled by default.
*
* @return <code>true</code>, iff this instance should be enabled by default.
* @throws NotDefinedException
* if this instance is not defined.
* @since 3.1
*/
boolean isDefaultEnabled() throws NotDefinedException;
/**
* Removes an instance of <code>IActivityListener</code> listening
* for changes to properties of this instance.
*
* @param activityListener
* the instance to remove. Must not be <code>null</code>.
* If an attempt is made to remove an instance which is not
* already registered with this instance, no operation is
* performed.
*/
void removeActivityListener(IActivityListener activityListener);
/**
* Return an expression used to enable and disable this activity. If the
* expression is not <code>null</code>, this activity will be entirely
* controlled by the expression state.
*
* @return The core expression, or <code>null</code>
* @since 3.4
*/
Expression getExpression();
}