content: /*******************************************************************************
   * 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.wst.jsdt.ui.actions;
  
  import org.eclipse.core.runtime.CoreException;
  import org.eclipse.jface.text.ITextSelection;
  import org.eclipse.ui.PlatformUI;
  import org.eclipse.wst.jsdt.internal.corext.refactoring.RefactoringAvailabilityTester;
  import org.eclipse.wst.jsdt.internal.corext.refactoring.code.ExtractMethodRefactoring;
  import org.eclipse.wst.jsdt.internal.ui.IJavaHelpContextIds;
  import org.eclipse.wst.jsdt.internal.ui.actions.ActionUtil;
  import org.eclipse.wst.jsdt.internal.ui.actions.SelectionConverter;
  import org.eclipse.wst.jsdt.internal.ui.javaeditor.JavaEditor;
  import org.eclipse.wst.jsdt.internal.ui.javaeditor.JavaTextSelection;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.RefactoringMessages;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.RefactoringSaveHelper;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.actions.RefactoringStarter;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.code.ExtractMethodWizard;
  import org.eclipse.wst.jsdt.internal.ui.util.ExceptionHandler;
  
  /**
   * Extracts the code selected inside a compilation unit editor into a new method.
   * Necessary arguments, exceptions and returns values are computed and an
   * appropriate method signature is generated.
   * 
   * <p>
   * This class may be instantiated; it is not intended to be subclassed.
   * </p>
   * 
   *
   * Provisional API: This class/interface is part of an interim API that is still under development and expected to
   * change significantly before reaching stability. It is being made available at this early stage to solicit feedback
   * from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken
   * (repeatedly) as the API evolves.
   */ 
  public class ExtractMethodAction extends SelectionDispatchAction {
  
  	private final JavaEditor fEditor;
  
  	/**
  	 * Note: This constructor is for internal use only. Clients should not call this constructor.
  	 * 
  	 * @param editor the JavaScript editor
  	 */
  	public ExtractMethodAction(JavaEditor editor) {
  		super(editor.getEditorSite());
  		setText(RefactoringMessages.ExtractMethodAction_label);
  		fEditor= editor;
  		setEnabled(SelectionConverter.getInputAsCompilationUnit(fEditor) != null);
  		PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.EXTRACT_METHOD_ACTION);
  	}
  
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction
  	 */		
  	public void selectionChanged(ITextSelection selection) {
  		setEnabled(selection.getLength() == 0 ? false : fEditor != null && SelectionConverter.getInputAsCompilationUnit(fEditor) != null);
  	}
  
  	/**
  	 * Note: This method is for internal use only. Clients should not call this method.
  	 */
  	public void selectionChanged(JavaTextSelection selection) {
  		setEnabled(RefactoringAvailabilityTester.isExtractMethodAvailable(selection));
  	}
  	
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction
  	 */		
  	public void run(ITextSelection selection) {
  		if (!ActionUtil.isEditable(fEditor))
  			return;
  		try{
  			final ExtractMethodRefactoring refactoring= new ExtractMethodRefactoring(SelectionConverter.getInputAsCompilationUnit(fEditor), selection.getOffset(), selection.getLength());
  			new RefactoringStarter().activate(refactoring, new ExtractMethodWizard(refactoring), getShell(), RefactoringMessages.ExtractMethodAction_dialog_title, RefactoringSaveHelper.SAVE_NOTHING);
  		} catch (CoreException e){
  			ExceptionHandler.handle(e, RefactoringMessages.ExtractMethodAction_dialog_title, RefactoringMessages.NewTextRefactoringAction_exception); 
  		}
  	}
  }
  