IExpressionManager.java :  » IDE-Eclipse » debug » org » eclipse » debug » core » Java Open Source

/*******************************************************************************
 * Copyright (c) 2000, 2008 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.debug.core;


import org.eclipse.debug.core.model.IExpression;
import org.eclipse.debug.core.model.IWatchExpression;
import org.eclipse.debug.core.model.IWatchExpressionDelegate;

/**
 * The expression manager manages the collection of registered
 * expressions in the workspace. An expression is a snippet of code
 * that can be evaluated to produce a value. Expression creation
 * and evaluation are client responsibilities.
 * <p>
 * Clients interested in expression change notification may
 * register with the expression manager - see
 * <code>IExpressionListener</code> and <code>IExpressionsListener</code>.
 * </p>
 * @see org.eclipse.debug.core.model.IExpression
 * @see org.eclipse.debug.core.IExpressionListener
 * @see org.eclipse.debug.core.IExpressionsListener
 * @since 2.0
 * @noimplement This interface is not intended to be implemented by clients.
 * @noextend This interface is not intended to be extended by clients.
 */
public interface IExpressionManager {
  /**
   * Adds the given expression to the collection of registered expressions
   * in the workspace and notifies all registered listeners. This has no effect
   * if the given expression is already registered.
   *
   * @param expression the expression to add
   */
  public void addExpression(IExpression expression);
  
  /**
   * Adds the given expressions to the collection of registered expressions
   * in the workspace and notifies all registered listeners. Has no effect
   * on expressions already registered.
   *
   * @param expressions the expressions to add
   * @since 2.1
   */
  public void addExpressions(IExpression[] expressions);
  
  /**
   * Creates and returns a new watch expression with the
   * given text. The returned expression is <b>not</b> added to
   * this manager.
   * 
   * @return new watch expression
   * @param expressionText the text for the new expression
   * @since 3.0
   */
  public IWatchExpression newWatchExpression(String expressionText);
    
  /**
   * Returns a collection of all registered expressions, 
   * possibly empty.
   *
   * @return an array of expressions
   */
  public IExpression[] getExpressions();
  
  /**
   * Returns whether there are any registered expressions
   * 
   * @return whether there are any registered expressions
   */
  public boolean hasExpressions();
  
  /**
   * Returns a collection of all expressions registered for the
   * given debug model,possibly empty.
   *
   * @param modelIdentifier identifier of a debug model plug-in
   * @return an array of expressions
   */
  public IExpression[] getExpressions(String modelIdentifier);
    
  /**
   * Removes the given expression from the expression manager,
   * and notifies all registered listeners. Has no effect if the
   * given expression is not currently registered.
   *
   * @param expression the expression to remove
   */
  public void removeExpression(IExpression expression);
  
  /**
   * Removes the given expressions from the collection of registered expressions
   * in the workspace and notifies all registered listeners. Has no effect
   * on expressions not already registered.
   *
   * @param expressions the expressions to remove
   * @since 2.1
   */
  public void removeExpressions(IExpression[] expressions);    

  /**
   * Adds the given listener to the collection of registered expression listeners.
   * Has no effect if an identical listener is already registered.
   *
   * @param listener the listener to add
   */
  public void addExpressionListener(IExpressionListener listener);

  /**
   * Removes the given listener from the collection of registered expression listeners.
   * Has no effect if an identical listener is not already registered.
   *
   * @param listener the listener to remove  
   */
  public void removeExpressionListener(IExpressionListener listener);
  
  /**
   * Adds the given listener to the collection of registered expression listeners.
   * Has no effect if an identical listener is already registered.
   *
   * @param listener the listener to add
   * @since 2.1
   */
  public void addExpressionListener(IExpressionsListener listener);

  /**
   * Removes the given listener from the collection of registered expression listeners.
   * Has no effect if an identical listener is not already registered.
   *
   * @param listener the listener to remove  
   * @since 2.1
   */
  public void removeExpressionListener(IExpressionsListener listener);
  
  /**
   * Returns a new watch expression delegate for the given debug
   * model or <code>null</code> if no delegate is available.
   * 
   * @param id the unique identifier of a debug model for which a
   *  watch expression delegate has been contributed
   * @return a watch expression delegate associated with the given model
   *     or <code>null</code> if none
   * @since 3.0
   * @see IWatchExpressionDelegate
   */
  public IWatchExpressionDelegate newWatchExpressionDelegate(String id);
    
    /**
     * Returns whether a watch expression delegate has been contributed for
     * the given debug model.
     * 
     * @param id the unique identifier of a debug model
     * @return whether a watch expression delegate has been contributed for
     *    the given debug model
     * @since 3.1
     * @see IWatchExpressionDelegate
     */    
    public boolean hasWatchExpressionDelegate(String id);
}