org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/texteditor/IncrementalFindTarget.java - platform/eclipse.platform.text - Git at Google

 /*******************************************************************************
  * 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
  *     Felix Pahl (fpahl@web.de) - fixed https://bugs.eclipse.org/bugs/show_bug.cgi?id=51820
  *******************************************************************************/

 package org.eclipse.ui.texteditor;

 import java.util.Stack;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.custom.VerifyKeyListener;
 import org.eclipse.swt.events.FocusEvent;
 import org.eclipse.swt.events.FocusListener;
 import org.eclipse.swt.events.MouseEvent;
 import org.eclipse.swt.events.MouseListener;
 import org.eclipse.swt.events.VerifyEvent;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.Point;

 import org.eclipse.core.commands.ExecutionEvent;
 import org.eclipse.core.commands.ExecutionException;
 import org.eclipse.core.commands.IExecutionListener;
 import org.eclipse.core.commands.NotHandledException;

 import org.eclipse.core.runtime.Assert;

 import org.eclipse.jface.action.IStatusLineManager;
 import org.eclipse.jface.util.Util;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.ISelectionChangedListener;
 import org.eclipse.jface.viewers.ISelectionProvider;
 import org.eclipse.jface.viewers.SelectionChangedEvent;

 import org.eclipse.jface.text.IFindReplaceTarget;
 import org.eclipse.jface.text.IFindReplaceTargetExtension;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.ITextListener;
 import org.eclipse.jface.text.ITextSelection;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.ITextViewerExtension;
 import org.eclipse.jface.text.ITextViewerExtension5;
 import org.eclipse.jface.text.TextEvent;

 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.commands.ICommandService;
 import org.eclipse.ui.internal.texteditor.NLSUtility;

 /**
  * An incremental find target. Replace is always disabled.
  * @since 2.0
  */
 class IncrementalFindTarget implements IFindReplaceTarget, IFindReplaceTargetExtension, VerifyKeyListener, MouseListener, FocusListener, ISelectionChangedListener, ITextListener, IExecutionListener {

 	/** The string representing rendered tab */
 	private final static String TAB= EditorMessages.Editor_FindIncremental_render_tab;
 	/**
 	 * The string representing "Reverse Incremental Find"
 	 * @since 3.0
 	 */
 	private final static String FIELD_NAME= EditorMessages.Editor_FindIncremental_name;
 	/**
 	 * The string representing "Incremental Find"
 	 * @since 3.0
 	 */
 	private final static String REVERSE_FIELD_NAME= EditorMessages.Editor_FindIncremental_reverse_name;
 	/**
 	 * The string representing reverse
 	 * @since 2.1
 	 */
 	private final static String REVERSE= EditorMessages.Editor_FindIncremental_reverse;
 	/**
 	 * The string representing wrapped
 	 * @since 2.1
 	 */
 	private final static String WRAPPED= EditorMessages.Editor_FindIncremental_wrapped;
 	/** The text viewer to operate on */
 	private final ITextViewer fTextViewer;
 	/** The status line manager for output */
 	private final IStatusLineManager fStatusLine;
 	/** The find replace target to delegate find requests */
 	private final IFindReplaceTarget fTarget;
 	/** The current find string */
 	private StringBuffer fFindString= new StringBuffer();
 	/** The position of the first upper case character, -1 if none */
 	private int fCasePosition;
 	/**
 	 * The position in the stack of the first wrap search, -1 if none
 	 * @since 2.1
 	 */
 	private int fWrapPosition;
 	/** The position of the last successful find */
 	private int fCurrentIndex;
 	/** A flag indicating if last find was successful */
 	private boolean fFound;
 	/**
 	 * A flag indicating if the last search was forward
 	 * @since 2.1
 	 */
 	private boolean fForward= true;
 	/** A flag indicating listeners are installed. */
 	private boolean fInstalled;
 	/**
 	 * A flag indicating that a search is currently active.
 	 * Used to ignore selection callbacks generated by the incremental search itself.
 	 * @since 2.1
 	 */
 	private boolean fSearching;
 	/** The current find stack */
 	private Stack<SearchResult> fSessionStack;
 	/**
 	 * The previous search string
 	 * @since 2.1
 	 */
 	private String fPrevFindString= ""; //$NON-NLS-1$
 	/**
 	 * The previous position of the first upper case character, -1 if none
 	 * @since 3.0
 	 */
 	private int fPrevCasePosition= -1;
 	/**
 	 * The find status field.
 	 * @since 3.0
 	 */
 	private IStatusField fStatusField;
 	/**
 	 * Tells whether the status field implements
 	 * <code>IStatusFieldExtension</code>.
 	 * @see IStatusFieldExtension
 	 * @since 3.0
 	 */
 	private boolean fIsStatusFieldExtension;

 	/**
 	 * Data structure for a search result.
 	 * @since 2.1
 	 */
 	private class SearchResult {
 		int selection, length, index, findLength;
 		boolean found, forward;

 		/**
 		 * Creates a new search result data object and fills
 		 * it with the current values of this target.
 		 */
 		public SearchResult() {
 			Point p= fTarget.getSelection();
 			selection= p.x;
 			length= p.y;
 			index= fCurrentIndex;
 			findLength= fFindString.length();
 			found= fFound;
 			forward= fForward;
 		}

 	}

 	/**
 	 * Stores the search result.
 	 */
 	private void saveState() {
 		fSessionStack.push(new SearchResult());
 	}

 	/**
 	 * Restores the search result.
 	 *
 	 * @since 2.1
 	 */
 	private void restoreState() {

 		StyledText text= fTextViewer.getTextWidget();
 		if (text == null || text.isDisposed())
 			return;

 		SearchResult searchResult= null;
 		if (!fSessionStack.empty())
 			searchResult= fSessionStack.pop();

 		if (searchResult == null) {
 			text.getDisplay().beep();
 			return;
 		}

 		text.setSelectionRange(searchResult.selection, searchResult.length);
 		text.showSelection();

 		// relies on the contents of the StringBuffer
 		fFindString.setLength(searchResult.findLength);
 		fCurrentIndex= searchResult.index;
 		fFound= searchResult.found;
 		fForward= searchResult.forward;

 		// Recalculate the indices
 		if (fFindString.length() <= fCasePosition)
 			fCasePosition= -1;
 		if (fSessionStack.size() < fWrapPosition)
 			fWrapPosition= -1;
 	}

 	/**
 	 * Sets the direction for the next search.
 	 * This can be called before <code>beginSession</code> to set the initial search direction.
 	 * @param forward <code>true</code> if the next search should be forward
 	 * @see #beginSession()
 	 * @since 2.1
 	 */
 	public void setDirection(boolean forward) {
 		fForward= forward;
 	}

 	/**
 	 * Creates an instance of an incremental find target.
 	 * @param viewer the text viewer to operate on
 	 * @param manager the status line manager for output
 	 */
 	public IncrementalFindTarget(ITextViewer viewer, IStatusLineManager manager) {
 		Assert.isNotNull(viewer);
 		Assert.isNotNull(manager);
 		fTextViewer= viewer;
 		fStatusLine= manager;
 		fTarget= viewer.getFindReplaceTarget();
 	}

 	@Override
 	public boolean canPerformFind() {
 		return fTarget.canPerformFind();
 	}

 	@Override
 	public int findAndSelect(int offset, String findString, boolean searchForward, boolean caseSensitive, boolean wholeWord) {
 		return fTarget.findAndSelect(offset, findString, searchForward, caseSensitive, wholeWord);
 	}

 	@Override
 	public Point getSelection() {
 		return fTarget.getSelection();
 	}

 	@Override
 	public String getSelectionText() {
 		return fTarget.getSelectionText();
 	}

 	@Override
 	public boolean isEditable() {
 		return false;
 	}

 	@Override
 	public void replaceSelection(String text) {
 	}

 	@Override
 	public void beginSession() {
 		fSearching= true;

 		// Workaround since some accelerators get handled directly by the OS
 		if (fInstalled) {
 			saveState();
 			repeatSearch(fForward);
 			updateStatus();
 			fSearching= false;
 			return;
 		}

 		fFindString.setLength(0);
 		fSessionStack= new Stack<>();
 		fCasePosition= -1;
 		fWrapPosition= -1;
 		fFound= true;

 		// clear initial selection
 		StyledText text= fTextViewer.getTextWidget();
 		if (text != null && !text.isDisposed()) {
 			fCurrentIndex= text.getCaretOffset();
 			text.setSelection(fCurrentIndex);
 		} else {
 			fCurrentIndex= 0;
 		}

 		install();

 		// Set the mark
 		if (fTextViewer instanceof ITextViewerExtension) {
 			int modelOffset;
 			if (fTextViewer instanceof ITextViewerExtension5)
 				modelOffset= fCurrentIndex == -1 ? -1 : ((ITextViewerExtension5)fTextViewer).widgetOffset2ModelOffset(fCurrentIndex);
 			else
 				modelOffset= fCurrentIndex;
 			((ITextViewerExtension)fTextViewer).setMark(modelOffset);
 		}

 		updateStatus();

 		if (fTarget instanceof IFindReplaceTargetExtension)
 			((IFindReplaceTargetExtension) fTarget).beginSession();

 		fSearching= false;
 	}

 	@Override
 	public void endSession() {
 		if (fTarget instanceof IFindReplaceTargetExtension)
 			((IFindReplaceTargetExtension) fTarget).endSession();

 		// will uninstall itself
 	}

 	@Override
 	public IRegion getScope() {
 		return null;
 	}

 	@Override
 	public void setScope(IRegion scope) {
 	}

 	@Override
 	public void setReplaceAllMode(boolean replaceAll) {
 	}

 	/**
 	 * Installs this target. I.e. adds all required listeners.
 	 */
 	private void install() {

 		if (fInstalled)
 			return;

 		StyledText text= fTextViewer.getTextWidget();
 		if (text == null)
 			return;

 		text.addMouseListener(this);
 		text.addFocusListener(this);
 		fTextViewer.addTextListener(this);

 		ISelectionProvider selectionProvider= fTextViewer.getSelectionProvider();
 		if (selectionProvider != null)
 			selectionProvider.addSelectionChangedListener(this);

 		if (fTextViewer instanceof ITextViewerExtension)
 			((ITextViewerExtension) fTextViewer).prependVerifyKeyListener(this);
 		else
 			text.addVerifyKeyListener(this);

 		ICommandService commandService= PlatformUI.getWorkbench().getAdapter(ICommandService.class);
 		if (commandService != null)
 			commandService.addExecutionListener(this);

 		fInstalled= true;
 	}

 	/**
 	 * Uninstalls itself. I.e. removes all listeners installed in <code>install</code>.
 	 */
 	private void uninstall() {

 		fTextViewer.removeTextListener(this);

 		ISelectionProvider selectionProvider= fTextViewer.getSelectionProvider();
 		if (selectionProvider != null)
 			selectionProvider.removeSelectionChangedListener(this);

 		StyledText text= fTextViewer.getTextWidget();
 		if (text != null) {
 			text.removeMouseListener(this);
 			text.removeFocusListener(this);
 		}

 		if (fTextViewer instanceof ITextViewerExtension) {
 			((ITextViewerExtension) fTextViewer).removeVerifyKeyListener(this);

 		} else {
 			if (text != null)
 				text.removeVerifyKeyListener(this);
 		}

 		ICommandService commandService= PlatformUI.getWorkbench().getAdapter(ICommandService.class);
 		if (commandService != null)
 			commandService.removeExecutionListener(this);

 		fInstalled= false;
 	}

 	/**
 	 * Updates the status line.
 	 * @since 2.1
 	 */
 	private void updateStatus() {

 		if (!fInstalled)
 			return;

 		String string= fFindString.toString();
 		String wrapPrefix= fWrapPosition == -1 ? "" : WRAPPED; //$NON-NLS-1$
 		String reversePrefix= fForward ? "" : REVERSE; //$NON-NLS-1$

 		if (!fFound) {
 			String pattern= EditorMessages.Editor_FindIncremental_not_found_pattern;
 			statusError(NLSUtility.format(pattern, new Object[] { reversePrefix, wrapPrefix, string }));

 		} else if (string.length() == 0) {
 			if (fForward)
 				statusMessage(FIELD_NAME);
 			else
 				statusMessage(REVERSE_FIELD_NAME);
 		} else if (!fForward || fWrapPosition > -1) {
 			String pattern= EditorMessages.Editor_FindIncremental_found_pattern;
 			statusMessage(NLSUtility.format(pattern, new Object[] { reversePrefix, wrapPrefix, string }));
 		} else {
 			statusMessage(string);
 		}
 	}

 	@Override
 	public void verifyKey(VerifyEvent event) {

 		if (!event.doit)
 			return;

 		fSearching= true;
 		if (event.character == 0) {

 			switch (event.keyCode) {

 			// ALT, CTRL, ARROW_LEFT, ARROW_RIGHT == leave
 			case SWT.ARROW_LEFT:
 			case SWT.ARROW_RIGHT:
 			case SWT.HOME:
 			case SWT.END:
 			case SWT.PAGE_DOWN:
 			case SWT.PAGE_UP:
 				leave();
 				break;

 			case SWT.ARROW_DOWN:
 				saveState();
 				setDirection(true);
 				repeatSearch(fForward);
 				event.doit= false;
 				break;

 			case SWT.ARROW_UP:
 				saveState();
 				setDirection(false);
 				repeatSearch(fForward);
 				event.doit= false;
 				break;
 			}

 		// event.character != 0
 		} else {

 			switch (event.character) {

 			// ESC, CR = quit
 			case 0x1B:
 			case 0x0D:
 				leave();
 				event.doit= false;
 				break;

 			// backspace	and delete
 			case 0x08:
 			case 0x7F:
 				restoreState();
 				event.doit= false;
 				break;

 			default:
 				int stateMask= event.stateMask;
 				if (stateMask == 0
 						|| stateMask == SWT.SHIFT
 						|| !Util.isMac() && stateMask == (SWT.ALT | SWT.CTRL) // AltGr (see bug 43049)
 						|| Util.isMac() && (stateMask == (SWT.ALT | SWT.SHIFT) || stateMask == SWT.ALT) ) { // special chars on Mac (bug 272994)
 					saveState();
 					addCharSearch(event.character);
 					event.doit= false;
 				}
 				break;
 			}
 		}
 		updateStatus();
 		fSearching= false;
 	}

 	/**
 	 * Repeats the last search while possibly changing the direction.
 	 *
 	 * @param forward <code>true</code> iff the next search should be forward
 	 * @return if the search was successful
 	 * @since 2.1
 	 */
 	private boolean repeatSearch(boolean forward) {
 		if (fFindString.length() == 0) {
 			fFindString= new StringBuffer(fPrevFindString);
 			fCasePosition= fPrevCasePosition;
 		}

 		String string= fFindString.toString();
 		if (string.length() == 0) {
 			fFound= true;
 			return true;
 		}

 		StyledText text= fTextViewer.getTextWidget();
 		// Cannot use fTarget.getSelection since that does not return which side of the
 		// selection the caret is on.
 		int startIndex= text.getCaretOffset();
 		if (!forward)
 			startIndex -= 1;

 		// Check to see if a wrap is necessary
 		if (!fFound && (fForward == forward)) {
 			startIndex= -1;
 			if (fWrapPosition == -1)
 				fWrapPosition= fSessionStack.size();
 		}
 		fForward = forward;

 		// Find the string
 		text.setRedraw(false);
 		int index= fTarget.findAndSelect(startIndex, string, fForward, fCasePosition != -1, false);

 		// Set the caret on the left if the search is reversed
 		if (!forward) {
 			Point p= fTarget.getSelection();
 			text.setSelectionRange(p.x + p.y, -p.y);
 			p= null;
 		}
 		text.setRedraw(true);

 		// Take appropriate action
 		boolean found = (index != -1);
 		if (!found && fFound) {
 			text= fTextViewer.getTextWidget();
 			if (text != null && !text.isDisposed())
 				text.getDisplay().beep();
 		}

 		if (found)
 			fCurrentIndex= startIndex;

 		fFound= found;
 		return found;
 	}

 	/**
 	 * Adds the given character to the search string and repeats the search with the last parameters.
 	 *
 	 * @param c the character to append to the search pattern
 	 * @return <code>true</code> the search found a match
 	 * @since 2.1
 	 */
 	private boolean addCharSearch(char c) {
 		// Add char to pattern
 		if (fCasePosition == -1 && Character.isUpperCase(c) && Character.toLowerCase(c) != c)
 			fCasePosition= fFindString.length();

 		fFindString.append(c);
 		String string= fFindString.toString();
 		StyledText text= fTextViewer.getTextWidget();

 		text.setRedraw(false);
 		int index= fTarget.findAndSelect(fCurrentIndex, string, fForward, fCasePosition != -1, false);

 		// Set the caret on the left if the search is reversed
 		if (!fForward) {
 			Point p= fTarget.getSelection();
 			text.setSelectionRange(p.x + p.y, -p.y);
 		}
 		text.setRedraw(true);

 		// Take appropriate action
 		boolean found = (index != -1);
 		if (!found && fFound) {
 			text= fTextViewer.getTextWidget();
 			if (text != null && !text.isDisposed())
 				text.getDisplay().beep();
 		}

 		fFound= found;
 		return found;
 	}

 	/**
 	 * Leaves this incremental search session.
 	 */
 	private void leave() {
 		if (fFindString.length() != 0) {
 			fPrevFindString= fFindString.toString();
 			fPrevCasePosition= fCasePosition;
 		}
 		statusClear();
 		uninstall();
 		fSessionStack = null;
 	}

 	@Override
 	public void textChanged(TextEvent event) {
 		if (event.getDocumentEvent() != null)
 			leave();
 	}

 	/*
 	 * @see MouseListener##mouseDoubleClick(MouseEvent)
 	 */
 	@Override
 	public void mouseDoubleClick(MouseEvent e) {
 		leave();
 	}

 	@Override
 	public void mouseDown(MouseEvent e) {
 		leave();
 	}

 	@Override
 	public void mouseUp(MouseEvent e) {
 		leave();
 	}

 	@Override
 	public void focusGained(FocusEvent e) {
 		leave();
 	}

 	@Override
 	public void focusLost(FocusEvent e) {
 		leave();
 	}

 	/**
 	 * Sets the given string as status message, clears the status error message.
 	 * @param string the status message
 	 */
 	private void statusMessage(String string) {
 		if (fStatusField != null) {
 			if (fIsStatusFieldExtension) {
 				((IStatusFieldExtension)fStatusField).setErrorText(null);
 				fStatusField.setText(escapeTabs(string));
 				((IStatusFieldExtension)fStatusField).setVisible(true);
 				fStatusLine.update(true);
 			} else {
 				fStatusLine.setErrorMessage(null);
 				fStatusField.setText(escapeTabs(string));
 			}
 		} else {
 			fStatusLine.setErrorMessage(null);
 			fStatusLine.setMessage(escapeTabs(string));
 		}
 	}

 	/**
 	 * Sets the status error message, clears the status message.
 	 * @param string the status error message
 	 */
 	private void statusError(String string) {
 		if (fStatusField != null) {
 			if (fIsStatusFieldExtension) {
 				((IStatusFieldExtension)fStatusField).setErrorText(escapeTabs(string));
 				fStatusField.setText(""); //$NON-NLS-1$
 				((IStatusFieldExtension)fStatusField).setVisible(true);
 				fStatusLine.update(true);
 			} else {
 				fStatusLine.setErrorMessage(escapeTabs(string));
 				fStatusField.setText(""); //$NON-NLS-1$
 			}
 		} else {
 			fStatusLine.setErrorMessage(escapeTabs(string));
 			fStatusLine.setMessage(null);
 		}
 	}

 	/**
 	 * Clears the status message and the status error message.
 	 */
 	private void statusClear() {
 		if (fStatusField != null) {
 			if (fIsStatusFieldExtension) {
 				fStatusField.setText(""); //$NON-NLS-1$
 				((IStatusFieldExtension)fStatusField).setErrorText(null);
 				((IStatusFieldExtension)fStatusField).setVisible(false);
 				fStatusLine.update(true);
 			} else {
 				fStatusField.setText(""); //$NON-NLS-1$
 				fStatusLine.setErrorMessage(null);
 			}
 		} else {
 			fStatusLine.setErrorMessage(null);
 			fStatusLine.setMessage(null);
 		}
 	}

 	/**
 	 * Translates all tab characters into a proper status line presentation.
 	 * @param string the string in which to translate the tabs
 	 * @return the given string with all tab characters replace with a proper status line presentation
 	 */
 	private String escapeTabs(String string) {
 		StringBuffer buffer= new StringBuffer();

 		int begin= 0;
 		int end= string.indexOf('\t', begin);

 		while (end >= 0) {
 			buffer.append(string.substring(begin, end));
 			buffer.append(TAB);
 			begin= end + 1;
 			end= string.indexOf('\t', begin);
 		}
 		buffer.append(string.substring(begin));

 		return buffer.toString();
 	}

 	@Override
 	public Point getLineSelection() {
 		if (fTarget instanceof IFindReplaceTargetExtension)
 			return ((IFindReplaceTargetExtension) fTarget).getLineSelection();

 		return null; // XXX: should not return null
 	}

 	@Override
 	public void setSelection(int offset, int length) {
 		if (fTarget instanceof IFindReplaceTargetExtension)
 			((IFindReplaceTargetExtension) fTarget).setSelection(offset, length);
 	}

 	@Override
 	public void setScopeHighlightColor(Color color) {
 	}

 	@Override
 	public void selectionChanged(SelectionChangedEvent e) {
 		boolean ignore= false;
 		ISelection selection= e.getSelection();
 		if (selection instanceof ITextSelection) {
 			ITextSelection textSelection= (ITextSelection)selection;
 			Point range= getSelection();
 			ignore= textSelection.getOffset() + textSelection.getLength() == range.x + range.y;
 		}
 		if (!fSearching && !ignore)
 			leave();
 	}

 	/**
 	 * Sets the find status field for this incremental find target.
 	 *
 	 * @param statusField the status field
 	 * @since 3.0
 	 */
 	void setStatusField(IStatusField statusField) {
 		fStatusField= statusField;
 		fIsStatusFieldExtension= fStatusField instanceof IStatusFieldExtension;
 	}

 	@Override
 	public void notHandled(String commandId, NotHandledException exception) {
 	}

 	@Override
 	public void postExecuteFailure(String commandId, ExecutionException exception) {
 	}

 	@Override
 	public void postExecuteSuccess(String commandId, Object returnValue) {
 	}

 	@Override
 	public void preExecute(String commandId, ExecutionEvent event) {
 		if (IWorkbenchActionDefinitionIds.FIND_INCREMENTAL.equals(commandId)
 				|| IWorkbenchActionDefinitionIds.FIND_INCREMENTAL_REVERSE.equals(commandId))
 			return;
 		leave();
 	}
 }
	/*******************************************************************************
	* 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
	* Felix Pahl (fpahl@web.de) - fixed https://bugs.eclipse.org/bugs/show_bug.cgi?id=51820
	*******************************************************************************/

	package org.eclipse.ui.texteditor;

	import java.util.Stack;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.StyledText;
	import org.eclipse.swt.custom.VerifyKeyListener;
	import org.eclipse.swt.events.FocusEvent;
	import org.eclipse.swt.events.FocusListener;
	import org.eclipse.swt.events.MouseEvent;
	import org.eclipse.swt.events.MouseListener;
	import org.eclipse.swt.events.VerifyEvent;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.Point;

	import org.eclipse.core.commands.ExecutionEvent;
	import org.eclipse.core.commands.ExecutionException;
	import org.eclipse.core.commands.IExecutionListener;
	import org.eclipse.core.commands.NotHandledException;

	import org.eclipse.core.runtime.Assert;

	import org.eclipse.jface.action.IStatusLineManager;
	import org.eclipse.jface.util.Util;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.ISelectionChangedListener;
	import org.eclipse.jface.viewers.ISelectionProvider;
	import org.eclipse.jface.viewers.SelectionChangedEvent;

	import org.eclipse.jface.text.IFindReplaceTarget;
	import org.eclipse.jface.text.IFindReplaceTargetExtension;
	import org.eclipse.jface.text.IRegion;
	import org.eclipse.jface.text.ITextListener;
	import org.eclipse.jface.text.ITextSelection;
	import org.eclipse.jface.text.ITextViewer;
	import org.eclipse.jface.text.ITextViewerExtension;
	import org.eclipse.jface.text.ITextViewerExtension5;
	import org.eclipse.jface.text.TextEvent;

	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.commands.ICommandService;
	import org.eclipse.ui.internal.texteditor.NLSUtility;

	/**
	* An incremental find target. Replace is always disabled.
	* @since 2.0
	*/
	class IncrementalFindTarget implements IFindReplaceTarget, IFindReplaceTargetExtension, VerifyKeyListener, MouseListener, FocusListener, ISelectionChangedListener, ITextListener, IExecutionListener {

	/** The string representing rendered tab */
	private final static String TAB= EditorMessages.Editor_FindIncremental_render_tab;
	/**
	* The string representing "Reverse Incremental Find"
	* @since 3.0
	*/
	private final static String FIELD_NAME= EditorMessages.Editor_FindIncremental_name;
	/**
	* The string representing "Incremental Find"
	* @since 3.0
	*/
	private final static String REVERSE_FIELD_NAME= EditorMessages.Editor_FindIncremental_reverse_name;
	/**
	* The string representing reverse
	* @since 2.1
	*/
	private final static String REVERSE= EditorMessages.Editor_FindIncremental_reverse;
	/**
	* The string representing wrapped
	* @since 2.1
	*/
	private final static String WRAPPED= EditorMessages.Editor_FindIncremental_wrapped;
	/** The text viewer to operate on */
	private final ITextViewer fTextViewer;
	/** The status line manager for output */
	private final IStatusLineManager fStatusLine;
	/** The find replace target to delegate find requests */
	private final IFindReplaceTarget fTarget;
	/** The current find string */
	private StringBuffer fFindString= new StringBuffer();
	/** The position of the first upper case character, -1 if none */
	private int fCasePosition;
	/**
	* The position in the stack of the first wrap search, -1 if none
	* @since 2.1
	*/
	private int fWrapPosition;
	/** The position of the last successful find */
	private int fCurrentIndex;
	/** A flag indicating if last find was successful */
	private boolean fFound;
	/**
	* A flag indicating if the last search was forward
	* @since 2.1
	*/
	private boolean fForward= true;
	/** A flag indicating listeners are installed. */
	private boolean fInstalled;
	/**
	* A flag indicating that a search is currently active.
	* Used to ignore selection callbacks generated by the incremental search itself.
	* @since 2.1
	*/
	private boolean fSearching;
	/** The current find stack */
	private Stack<SearchResult> fSessionStack;
	/**
	* The previous search string
	* @since 2.1
	*/
	private String fPrevFindString= ""; //$NON-NLS-1$
	/**
	* The previous position of the first upper case character, -1 if none
	* @since 3.0
	*/
	private int fPrevCasePosition= -1;
	/**
	* The find status field.
	* @since 3.0
	*/
	private IStatusField fStatusField;
	/**
	* Tells whether the status field implements
	* <code>IStatusFieldExtension</code>.
	* @see IStatusFieldExtension
	* @since 3.0
	*/
	private boolean fIsStatusFieldExtension;

	/**
	* Data structure for a search result.
	* @since 2.1
	*/
	private class SearchResult {
	int selection, length, index, findLength;
	boolean found, forward;

	/**
	* Creates a new search result data object and fills
	* it with the current values of this target.
	*/
	public SearchResult() {
	Point p= fTarget.getSelection();
	selection= p.x;
	length= p.y;
	index= fCurrentIndex;
	findLength= fFindString.length();
	found= fFound;
	forward= fForward;
	}

	}

	/**
	* Stores the search result.
	*/
	private void saveState() {
	fSessionStack.push(new SearchResult());
	}

	/**
	* Restores the search result.
	*
	* @since 2.1
	*/
	private void restoreState() {

	StyledText text= fTextViewer.getTextWidget();
	if (text == null \|\| text.isDisposed())
	return;

	SearchResult searchResult= null;
	if (!fSessionStack.empty())
	searchResult= fSessionStack.pop();

	if (searchResult == null) {
	text.getDisplay().beep();
	return;
	}

	text.setSelectionRange(searchResult.selection, searchResult.length);
	text.showSelection();

	// relies on the contents of the StringBuffer
	fFindString.setLength(searchResult.findLength);
	fCurrentIndex= searchResult.index;
	fFound= searchResult.found;
	fForward= searchResult.forward;

	// Recalculate the indices
	if (fFindString.length() <= fCasePosition)
	fCasePosition= -1;
	if (fSessionStack.size() < fWrapPosition)
	fWrapPosition= -1;
	}

	/**
	* Sets the direction for the next search.
	* This can be called before <code>beginSession</code> to set the initial search direction.
	* @param forward <code>true</code> if the next search should be forward
	* @see #beginSession()
	* @since 2.1
	*/
	public void setDirection(boolean forward) {
	fForward= forward;
	}

	/**
	* Creates an instance of an incremental find target.
	* @param viewer the text viewer to operate on
	* @param manager the status line manager for output
	*/
	public IncrementalFindTarget(ITextViewer viewer, IStatusLineManager manager) {
	Assert.isNotNull(viewer);
	Assert.isNotNull(manager);
	fTextViewer= viewer;
	fStatusLine= manager;
	fTarget= viewer.getFindReplaceTarget();
	}

	@Override
	public boolean canPerformFind() {
	return fTarget.canPerformFind();
	}

	@Override
	public int findAndSelect(int offset, String findString, boolean searchForward, boolean caseSensitive, boolean wholeWord) {
	return fTarget.findAndSelect(offset, findString, searchForward, caseSensitive, wholeWord);
	}

	@Override
	public Point getSelection() {
	return fTarget.getSelection();
	}

	@Override
	public String getSelectionText() {
	return fTarget.getSelectionText();
	}

	@Override
	public boolean isEditable() {
	return false;
	}

	@Override
	public void replaceSelection(String text) {
	}

	@Override
	public void beginSession() {
	fSearching= true;

	// Workaround since some accelerators get handled directly by the OS
	if (fInstalled) {
	saveState();
	repeatSearch(fForward);
	updateStatus();
	fSearching= false;
	return;
	}

	fFindString.setLength(0);
	fSessionStack= new Stack<>();
	fCasePosition= -1;
	fWrapPosition= -1;
	fFound= true;

	// clear initial selection
	StyledText text= fTextViewer.getTextWidget();
	if (text != null && !text.isDisposed()) {
	fCurrentIndex= text.getCaretOffset();
	text.setSelection(fCurrentIndex);
	} else {
	fCurrentIndex= 0;
	}

	install();

	// Set the mark
	if (fTextViewer instanceof ITextViewerExtension) {
	int modelOffset;
	if (fTextViewer instanceof ITextViewerExtension5)
	modelOffset= fCurrentIndex == -1 ? -1 : ((ITextViewerExtension5)fTextViewer).widgetOffset2ModelOffset(fCurrentIndex);
	else
	modelOffset= fCurrentIndex;
	((ITextViewerExtension)fTextViewer).setMark(modelOffset);
	}

	updateStatus();

	if (fTarget instanceof IFindReplaceTargetExtension)
	((IFindReplaceTargetExtension) fTarget).beginSession();

	fSearching= false;
	}

	@Override
	public void endSession() {
	if (fTarget instanceof IFindReplaceTargetExtension)
	((IFindReplaceTargetExtension) fTarget).endSession();

	// will uninstall itself
	}

	@Override
	public IRegion getScope() {
	return null;
	}

	@Override
	public void setScope(IRegion scope) {
	}

	@Override
	public void setReplaceAllMode(boolean replaceAll) {
	}

	/**
	* Installs this target. I.e. adds all required listeners.
	*/
	private void install() {

	if (fInstalled)
	return;

	StyledText text= fTextViewer.getTextWidget();
	if (text == null)
	return;

	text.addMouseListener(this);
	text.addFocusListener(this);
	fTextViewer.addTextListener(this);

	ISelectionProvider selectionProvider= fTextViewer.getSelectionProvider();
	if (selectionProvider != null)
	selectionProvider.addSelectionChangedListener(this);

	if (fTextViewer instanceof ITextViewerExtension)
	((ITextViewerExtension) fTextViewer).prependVerifyKeyListener(this);
	else
	text.addVerifyKeyListener(this);

	ICommandService commandService= PlatformUI.getWorkbench().getAdapter(ICommandService.class);
	if (commandService != null)
	commandService.addExecutionListener(this);

	fInstalled= true;
	}

	/**
	* Uninstalls itself. I.e. removes all listeners installed in <code>install</code>.
	*/
	private void uninstall() {

	fTextViewer.removeTextListener(this);

	ISelectionProvider selectionProvider= fTextViewer.getSelectionProvider();
	if (selectionProvider != null)
	selectionProvider.removeSelectionChangedListener(this);

	StyledText text= fTextViewer.getTextWidget();
	if (text != null) {
	text.removeMouseListener(this);
	text.removeFocusListener(this);
	}

	if (fTextViewer instanceof ITextViewerExtension) {
	((ITextViewerExtension) fTextViewer).removeVerifyKeyListener(this);

	} else {
	if (text != null)
	text.removeVerifyKeyListener(this);
	}

	ICommandService commandService= PlatformUI.getWorkbench().getAdapter(ICommandService.class);
	if (commandService != null)
	commandService.removeExecutionListener(this);

	fInstalled= false;
	}

	/**
	* Updates the status line.
	* @since 2.1
	*/
	private void updateStatus() {

	if (!fInstalled)
	return;

	String string= fFindString.toString();
	String wrapPrefix= fWrapPosition == -1 ? "" : WRAPPED; //$NON-NLS-1$
	String reversePrefix= fForward ? "" : REVERSE; //$NON-NLS-1$

	if (!fFound) {
	String pattern= EditorMessages.Editor_FindIncremental_not_found_pattern;
	statusError(NLSUtility.format(pattern, new Object[] { reversePrefix, wrapPrefix, string }));

	} else if (string.length() == 0) {
	if (fForward)
	statusMessage(FIELD_NAME);
	else
	statusMessage(REVERSE_FIELD_NAME);
	} else if (!fForward \|\| fWrapPosition > -1) {
	String pattern= EditorMessages.Editor_FindIncremental_found_pattern;
	statusMessage(NLSUtility.format(pattern, new Object[] { reversePrefix, wrapPrefix, string }));
	} else {
	statusMessage(string);
	}
	}

	@Override
	public void verifyKey(VerifyEvent event) {

	if (!event.doit)
	return;

	fSearching= true;
	if (event.character == 0) {

	switch (event.keyCode) {

	// ALT, CTRL, ARROW_LEFT, ARROW_RIGHT == leave
	case SWT.ARROW_LEFT:
	case SWT.ARROW_RIGHT:
	case SWT.HOME:
	case SWT.END:
	case SWT.PAGE_DOWN:
	case SWT.PAGE_UP:
	leave();
	break;

	case SWT.ARROW_DOWN:
	saveState();
	setDirection(true);
	repeatSearch(fForward);
	event.doit= false;
	break;

	case SWT.ARROW_UP:
	saveState();
	setDirection(false);
	repeatSearch(fForward);
	event.doit= false;
	break;
	}

	// event.character != 0
	} else {

	switch (event.character) {

	// ESC, CR = quit
	case 0x1B:
	case 0x0D:
	leave();
	event.doit= false;
	break;

	// backspace and delete
	case 0x08:
	case 0x7F:
	restoreState();
	event.doit= false;
	break;

	default:
	int stateMask= event.stateMask;
	if (stateMask == 0
	\|\| stateMask == SWT.SHIFT
	\|\| !Util.isMac() && stateMask == (SWT.ALT \| SWT.CTRL) // AltGr (see bug 43049)
	\|\| Util.isMac() && (stateMask == (SWT.ALT \| SWT.SHIFT) \|\| stateMask == SWT.ALT) ) { // special chars on Mac (bug 272994)
	saveState();
	addCharSearch(event.character);
	event.doit= false;
	}
	break;
	}
	}
	updateStatus();
	fSearching= false;
	}

	/**
	* Repeats the last search while possibly changing the direction.
	*
	* @param forward <code>true</code> iff the next search should be forward
	* @return if the search was successful
	* @since 2.1
	*/
	private boolean repeatSearch(boolean forward) {
	if (fFindString.length() == 0) {
	fFindString= new StringBuffer(fPrevFindString);
	fCasePosition= fPrevCasePosition;
	}

	String string= fFindString.toString();
	if (string.length() == 0) {
	fFound= true;
	return true;
	}

	StyledText text= fTextViewer.getTextWidget();
	// Cannot use fTarget.getSelection since that does not return which side of the
	// selection the caret is on.
	int startIndex= text.getCaretOffset();
	if (!forward)
	startIndex -= 1;

	// Check to see if a wrap is necessary
	if (!fFound && (fForward == forward)) {
	startIndex= -1;
	if (fWrapPosition == -1)
	fWrapPosition= fSessionStack.size();
	}
	fForward = forward;

	// Find the string
	text.setRedraw(false);
	int index= fTarget.findAndSelect(startIndex, string, fForward, fCasePosition != -1, false);

	// Set the caret on the left if the search is reversed
	if (!forward) {
	Point p= fTarget.getSelection();
	text.setSelectionRange(p.x + p.y, -p.y);
	p= null;
	}
	text.setRedraw(true);

	// Take appropriate action
	boolean found = (index != -1);
	if (!found && fFound) {
	text= fTextViewer.getTextWidget();
	if (text != null && !text.isDisposed())
	text.getDisplay().beep();
	}

	if (found)
	fCurrentIndex= startIndex;

	fFound= found;
	return found;
	}

	/**
	* Adds the given character to the search string and repeats the search with the last parameters.
	*
	* @param c the character to append to the search pattern
	* @return <code>true</code> the search found a match
	* @since 2.1
	*/
	private boolean addCharSearch(char c) {
	// Add char to pattern
	if (fCasePosition == -1 && Character.isUpperCase(c) && Character.toLowerCase(c) != c)
	fCasePosition= fFindString.length();

	fFindString.append(c);
	String string= fFindString.toString();
	StyledText text= fTextViewer.getTextWidget();

	text.setRedraw(false);
	int index= fTarget.findAndSelect(fCurrentIndex, string, fForward, fCasePosition != -1, false);

	// Set the caret on the left if the search is reversed
	if (!fForward) {
	Point p= fTarget.getSelection();
	text.setSelectionRange(p.x + p.y, -p.y);
	}
	text.setRedraw(true);

	// Take appropriate action
	boolean found = (index != -1);
	if (!found && fFound) {
	text= fTextViewer.getTextWidget();
	if (text != null && !text.isDisposed())
	text.getDisplay().beep();
	}

	fFound= found;
	return found;
	}

	/**
	* Leaves this incremental search session.
	*/
	private void leave() {
	if (fFindString.length() != 0) {
	fPrevFindString= fFindString.toString();
	fPrevCasePosition= fCasePosition;
	}
	statusClear();
	uninstall();
	fSessionStack = null;
	}

	@Override
	public void textChanged(TextEvent event) {
	if (event.getDocumentEvent() != null)
	leave();
	}

	/*
	* @see MouseListener##mouseDoubleClick(MouseEvent)
	*/
	@Override
	public void mouseDoubleClick(MouseEvent e) {
	leave();
	}

	@Override
	public void mouseDown(MouseEvent e) {
	leave();
	}

	@Override
	public void mouseUp(MouseEvent e) {
	leave();
	}

	@Override
	public void focusGained(FocusEvent e) {
	leave();
	}

	@Override
	public void focusLost(FocusEvent e) {
	leave();
	}

	/**
	* Sets the given string as status message, clears the status error message.
	* @param string the status message
	*/
	private void statusMessage(String string) {
	if (fStatusField != null) {
	if (fIsStatusFieldExtension) {
	((IStatusFieldExtension)fStatusField).setErrorText(null);
	fStatusField.setText(escapeTabs(string));
	((IStatusFieldExtension)fStatusField).setVisible(true);
	fStatusLine.update(true);
	} else {
	fStatusLine.setErrorMessage(null);
	fStatusField.setText(escapeTabs(string));
	}
	} else {
	fStatusLine.setErrorMessage(null);
	fStatusLine.setMessage(escapeTabs(string));
	}
	}

	/**
	* Sets the status error message, clears the status message.
	* @param string the status error message
	*/
	private void statusError(String string) {
	if (fStatusField != null) {
	if (fIsStatusFieldExtension) {
	((IStatusFieldExtension)fStatusField).setErrorText(escapeTabs(string));
	fStatusField.setText(""); //$NON-NLS-1$
	((IStatusFieldExtension)fStatusField).setVisible(true);
	fStatusLine.update(true);
	} else {
	fStatusLine.setErrorMessage(escapeTabs(string));
	fStatusField.setText(""); //$NON-NLS-1$
	}
	} else {
	fStatusLine.setErrorMessage(escapeTabs(string));
	fStatusLine.setMessage(null);
	}
	}

	/**
	* Clears the status message and the status error message.
	*/
	private void statusClear() {
	if (fStatusField != null) {
	if (fIsStatusFieldExtension) {
	fStatusField.setText(""); //$NON-NLS-1$
	((IStatusFieldExtension)fStatusField).setErrorText(null);
	((IStatusFieldExtension)fStatusField).setVisible(false);
	fStatusLine.update(true);
	} else {
	fStatusField.setText(""); //$NON-NLS-1$
	fStatusLine.setErrorMessage(null);
	}
	} else {
	fStatusLine.setErrorMessage(null);
	fStatusLine.setMessage(null);
	}
	}

	/**
	* Translates all tab characters into a proper status line presentation.
	* @param string the string in which to translate the tabs
	* @return the given string with all tab characters replace with a proper status line presentation
	*/
	private String escapeTabs(String string) {
	StringBuffer buffer= new StringBuffer();

	int begin= 0;
	int end= string.indexOf('\t', begin);

	while (end >= 0) {
	buffer.append(string.substring(begin, end));
	buffer.append(TAB);
	begin= end + 1;
	end= string.indexOf('\t', begin);
	}
	buffer.append(string.substring(begin));

	return buffer.toString();
	}

	@Override
	public Point getLineSelection() {
	if (fTarget instanceof IFindReplaceTargetExtension)
	return ((IFindReplaceTargetExtension) fTarget).getLineSelection();

	return null; // XXX: should not return null
	}

	@Override
	public void setSelection(int offset, int length) {
	if (fTarget instanceof IFindReplaceTargetExtension)
	((IFindReplaceTargetExtension) fTarget).setSelection(offset, length);
	}

	@Override
	public void setScopeHighlightColor(Color color) {
	}

	@Override
	public void selectionChanged(SelectionChangedEvent e) {
	boolean ignore= false;
	ISelection selection= e.getSelection();
	if (selection instanceof ITextSelection) {
	ITextSelection textSelection= (ITextSelection)selection;
	Point range= getSelection();
	ignore= textSelection.getOffset() + textSelection.getLength() == range.x + range.y;
	}
	if (!fSearching && !ignore)
	leave();
	}

	/**
	* Sets the find status field for this incremental find target.
	*
	* @param statusField the status field
	* @since 3.0
	*/
	void setStatusField(IStatusField statusField) {
	fStatusField= statusField;
	fIsStatusFieldExtension= fStatusField instanceof IStatusFieldExtension;
	}

	@Override
	public void notHandled(String commandId, NotHandledException exception) {
	}

	@Override
	public void postExecuteFailure(String commandId, ExecutionException exception) {
	}

	@Override
	public void postExecuteSuccess(String commandId, Object returnValue) {
	}

	@Override
	public void preExecute(String commandId, ExecutionEvent event) {
	if (IWorkbenchActionDefinitionIds.FIND_INCREMENTAL.equals(commandId)
	\|\| IWorkbenchActionDefinitionIds.FIND_INCREMENTAL_REVERSE.equals(commandId))
	return;
	leave();
	}
	}