org.eclipse.jface.text/src/org/eclipse/jface/text/DocumentCommand.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
  *******************************************************************************/
 package org.eclipse.jface.text;

 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.ListIterator;
 import java.util.NoSuchElementException;

 import org.eclipse.swt.events.VerifyEvent;

 import org.eclipse.core.runtime.Assert;


 /**
  * Represents a text modification as a document replace command. The text
  * modification is given as a {@link org.eclipse.swt.events.VerifyEvent} and
  * translated into a document replace command relative to a given offset. A
  * document command can also be used to initialize a given
  * <code>VerifyEvent</code>.
  * <p>
  * A document command can also represent a list of related changes.</p>
  */
 public class DocumentCommand {

 	/**
 	 * A command which is added to document commands.
 	 * @since 2.1
 	 */
 	private static class Command implements Comparable<Command> {
 		/** The offset of the range to be replaced */
 		private final int fOffset;
 		/** The length of the range to be replaced. */
 		private final int fLength;
 		/** The replacement text */
 		private final String fText;
 		/** The listener who owns this command */
 		private final IDocumentListener fOwner;

 		/**
 		 * Creates a new command with the given specification.
 		 *
 		 * @param offset the offset of the replace command
 		 * @param length the length of the replace command
 		 * @param text the text to replace with, may be <code>null</code>
 		 * @param owner the document command owner, may be <code>null</code>
 		 * @since 3.0
 		 */
 		public Command(int offset, int length, String text, IDocumentListener owner) {
 			if (offset < 0 || length < 0)
 				throw new IllegalArgumentException();
 			fOffset= offset;
 			fLength= length;
 			fText= text;
 			fOwner= owner;
 		}

 		/**
 		 * Executes the document command on the specified document.
 		 *
 		 * @param document the document on which to execute the command.
 		 * @throws BadLocationException in case this commands cannot be executed
 		 */
 		public void execute(IDocument document) throws BadLocationException {

 			if (fLength == 0 && fText == null)
 				return;

 			if (fOwner != null)
 				document.removeDocumentListener(fOwner);

 			document.replace(fOffset, fLength, fText);

 			if (fOwner != null)
 				document.addDocumentListener(fOwner);
 		}

 		@Override
 		public int compareTo(Command object) {
 			if (isEqual(object))
 				return 0;

 			Command command= object;

 			// diff middle points if not intersecting
 			if (fOffset + fLength <= command.fOffset || command.fOffset + command.fLength <= fOffset) {
 				int value= (2 * fOffset + fLength) - (2 * command.fOffset + command.fLength);
 				if (value != 0)
 					return value;
 			}
 			// the answer
 			return 42;
 		}

 		private boolean isEqual(Object object) {
 			if (object == this)
 				return true;
 			if (!(object instanceof Command))
 				return false;
 			final Command command= (Command) object;
 			return command.fOffset == fOffset && command.fLength == fLength;
 		}
 	}

 	/**
 	 * An iterator, which iterates in reverse over a list.
 	 *
 	 * @param <E> the type of elements returned by this iterator
 	 */
 	private static class ReverseListIterator<E> implements Iterator<E> {

 		/** The list iterator. */
 		private final ListIterator<E> fListIterator;

 		/**
 		 * Creates a reverse list iterator.
 		 * @param listIterator the iterator that this reverse iterator is based upon
 		 */
 		public ReverseListIterator(ListIterator<E> listIterator) {
 			if (listIterator == null)
 				throw new IllegalArgumentException();
 			fListIterator= listIterator;
 		}

 		@Override
 		public boolean hasNext() {
 			return fListIterator.hasPrevious();
 		}

 		@Override
 		public E next() {
 			return fListIterator.previous();
 		}

 		@Override
 		public void remove() {
 			throw new UnsupportedOperationException();
 		}
 	}

 	/**
 	 * A command iterator.
 	 */
 	private static class CommandIterator implements Iterator<Command> {

 		/** The command iterator. */
 		private final Iterator<Command> fIterator;

 		/** The original command. */
 		private Command fCommand;

 		/** A flag indicating the direction of iteration. */
 		private boolean fForward;

 		/**
 		 * Creates a command iterator.
 		 *
 		 * @param commands an ascending ordered list of commands
 		 * @param command the original command
 		 * @param forward the direction
 		 */
 		public CommandIterator(final List<Command> commands, final Command command, final boolean forward) {
 			if (commands == null || command == null)
 				throw new IllegalArgumentException();
 			fIterator= forward ? commands.iterator() : new ReverseListIterator<>(commands.listIterator(commands.size()));
 			fCommand= command;
 			fForward= forward;
 		}

 		@Override
 		public boolean hasNext() {
 			return fCommand != null || fIterator.hasNext();
 		}

 		@Override
 		public Command next() {

 			if (!hasNext())
 				throw new NoSuchElementException();

 			if (fCommand == null)
 				return fIterator.next();

 			if (!fIterator.hasNext()) {
 				final Command tempCommand= fCommand;
 				fCommand= null;
 				return tempCommand;
 			}

 			final Command command= fIterator.next();
 			final int compareValue= command.compareTo(fCommand);

 			if ((compareValue < 0) ^ !fForward) {
 				return command;

 			} else if ((compareValue > 0) ^ !fForward) {
 				final Command tempCommand= fCommand;
 				fCommand= command;
 				return tempCommand;

 			} else {
 				throw new IllegalArgumentException();
 			}
 		}

 		@Override
 		public void remove() {
 			throw new UnsupportedOperationException();
 		}
 	}

 	/** Must the command be updated */
 	public boolean doit= false;
 	/** The offset of the command. */
 	public int offset;
 	/** The length of the command */
 	public int length;
 	/** The text to be inserted */
 	public String text;
 	/**
 	 * The owner of the document command which will not be notified.
 	 * @since 2.1
 	 */
 	public IDocumentListener owner;
 	/**
 	 * The caret offset with respect to the document before the document command is executed.
 	 * @since 2.1
 	 */
 	public int caretOffset;
 	/**
 	 * Additional document commands.
 	 * @since 2.1
 	 */
 	private final List<Command> fCommands= new ArrayList<>();
 	/**
 	 * Indicates whether the caret should be shifted by this command.
 	 * @since 3.0
 	 */
 	public boolean shiftsCaret;


 	/**
 	 * Creates a new document command.
 	 */
 	protected DocumentCommand() {
 	}

 	/**
 	 * Translates a verify event into a document replace command using the given offset.
 	 *
 	 * @param event the event to be translated
 	 * @param modelRange the event range as model range
 	 */
 	void setEvent(VerifyEvent event, IRegion modelRange) {

 		doit= true;
 		text= event.text;

 		offset= modelRange.getOffset();
 		length= modelRange.getLength();

 		owner= null;
 		caretOffset= -1;
 		shiftsCaret= true;
 		fCommands.clear();
 	}

 	/**
 	 * Fills the given verify event with the replace text and the <code>doit</code>
 	 * flag of this document command. Returns whether the document command
 	 * covers the same range as the verify event considering the given offset.
 	 *
 	 * @param event the event to be changed
 	 * @param modelRange to be considered for range comparison
 	 * @return <code>true</code> if this command and the event cover the same range
 	 */
 	boolean fillEvent(VerifyEvent event, IRegion modelRange) {
 		event.text= text;
 		event.doit= (offset == modelRange.getOffset() && length == modelRange.getLength() && doit && caretOffset == -1);
 		return event.doit;
 	}

 	/**
 	 * Adds an additional replace command. The added replace command must not overlap
 	 * with existing ones. If the document command owner is not <code>null</code>, it will not
 	 * get document change notifications for the particular command.
 	 *
 	 * @param commandOffset the offset of the region to replace
 	 * @param commandLength the length of the region to replace
 	 * @param commandText the text to replace with, may be <code>null</code>
 	 * @param commandOwner the command owner, may be <code>null</code>
 	 * @throws BadLocationException if the added command intersects with an existing one
 	 * @since 2.1
 	 */
 	public void addCommand(int commandOffset, int commandLength, String commandText, IDocumentListener commandOwner) throws BadLocationException {
 		final Command command= new Command(commandOffset, commandLength, commandText, commandOwner);

 		if (intersects(command))
 			throw new BadLocationException();

 		final int index= Collections.binarySearch(fCommands, command);

 		// a command with exactly the same ranges exists already
 		if (index >= 0)
 			throw new BadLocationException();

 		// binary search result is defined as (-(insertionIndex) - 1)
 		final int insertionIndex= -(index + 1);

 		// overlaps to the right?
 		if (insertionIndex != fCommands.size() && intersects(fCommands.get(insertionIndex), command))
 			throw new BadLocationException();

 		// overlaps to the left?
 		if (insertionIndex != 0 && intersects(fCommands.get(insertionIndex - 1), command))
 			throw new BadLocationException();

 		fCommands.add(insertionIndex, command);
 	}

 	/**
 	 * Returns an iterator over the commands in ascending position order.
 	 * The iterator includes the original document command.
 	 * Commands cannot be removed.
 	 *
 	 * @return returns the command iterator
 	 */
 	public Iterator<Command> getCommandIterator() {
 		Command command= new Command(offset, length, text, owner);
 		return new CommandIterator(fCommands, command, true);
 	}

 	/**
 	 * Returns the number of commands including the original document command.
 	 *
 	 * @return returns the number of commands
 	 * @since 2.1
 	 */
 	public int getCommandCount() {
 		return 1 + fCommands.size();
 	}

 	/**
 	 * Returns whether the two given commands intersect.
 	 *
 	 * @param command0 the first command
 	 * @param command1 the second command
 	 * @return <code>true</code> if the commands intersect
 	 * @since 2.1
 	 */
 	private boolean intersects(Command command0, Command command1) {
 		// diff middle points if not intersecting
 		if (command0.fOffset + command0.fLength <= command1.fOffset || command1.fOffset + command1.fLength <= command0.fOffset)
 			return (2 * command0.fOffset + command0.fLength) - (2 * command1.fOffset + command1.fLength) == 0;
 		return true;
 	}

 	/**
 	 * Returns whether the given command intersects with this command.
 	 *
 	 * @param command the command
 	 * @return <code>true</code> if the command intersects with this command
 	 * @since 2.1
 	 */
 	private boolean intersects(Command command) {
 		// diff middle points if not intersecting
 		if (offset + length <= command.fOffset || command.fOffset + command.fLength <= offset)
 			return (2 * offset + length) - (2 * command.fOffset + command.fLength) == 0;
 		return true;
 	}

 	/**
 	 * Executes the document commands on a document.
 	 *
 	 * @param document the document on which to execute the commands
 	 * @throws BadLocationException in case access to the given document fails
 	 * @since 2.1
 	 */
 	void execute(IDocument document) throws BadLocationException {

 		if (length == 0 && text == null && fCommands.size() == 0)
 			return;

 		DefaultPositionUpdater updater= new DefaultPositionUpdater(getCategory());
 		Position caretPosition= null;
 		try {
 			if (updateCaret()) {
 				document.addPositionCategory(getCategory());
 				document.addPositionUpdater(updater);
 				caretPosition= new Position(caretOffset);
 				document.addPosition(getCategory(), caretPosition);
 			}

 			final Command originalCommand= new Command(offset, length, text, owner);
 			for (final Iterator<Command> iterator= new CommandIterator(fCommands, originalCommand, false); iterator.hasNext(); )
 				iterator.next().execute(document);

 		} catch (BadLocationException e) {
 			// ignore
 		} catch (BadPositionCategoryException e) {
 			// ignore
 		} finally {
 			if (updateCaret()) {
 				document.removePositionUpdater(updater);
 				try {
 					document.removePositionCategory(getCategory());
 				} catch (BadPositionCategoryException e) {
 					Assert.isTrue(false);
 				}
 				caretOffset= caretPosition.getOffset();
 			}
 		}
 	}

 	/**
 	 * Returns <code>true</code> if the caret offset should be updated, <code>false</code> otherwise.
 	 *
 	 * @return <code>true</code> if the caret offset should be updated, <code>false</code> otherwise
 	 * @since 3.0
 	 */
 	private boolean updateCaret() {
 		return shiftsCaret && caretOffset != -1;
 	}

 	/**
 	 * Returns the position category for the caret offset position.
 	 *
 	 * @return the position category for the caret offset position
 	 * @since 3.0
 	 */
 	private String getCategory() {
 		return toString();
 	}

 }
	/*******************************************************************************
	* 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.jface.text;

	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.Iterator;
	import java.util.List;
	import java.util.ListIterator;
	import java.util.NoSuchElementException;

	import org.eclipse.swt.events.VerifyEvent;

	import org.eclipse.core.runtime.Assert;


	/**
	* Represents a text modification as a document replace command. The text
	* modification is given as a {@link org.eclipse.swt.events.VerifyEvent} and
	* translated into a document replace command relative to a given offset. A
	* document command can also be used to initialize a given
	* <code>VerifyEvent</code>.
	* <p>
	* A document command can also represent a list of related changes.</p>
	*/
	public class DocumentCommand {

	/**
	* A command which is added to document commands.
	* @since 2.1
	*/
	private static class Command implements Comparable<Command> {
	/** The offset of the range to be replaced */
	private final int fOffset;
	/** The length of the range to be replaced. */
	private final int fLength;
	/** The replacement text */
	private final String fText;
	/** The listener who owns this command */
	private final IDocumentListener fOwner;

	/**
	* Creates a new command with the given specification.
	*
	* @param offset the offset of the replace command
	* @param length the length of the replace command
	* @param text the text to replace with, may be <code>null</code>
	* @param owner the document command owner, may be <code>null</code>
	* @since 3.0
	*/
	public Command(int offset, int length, String text, IDocumentListener owner) {
	if (offset < 0 \|\| length < 0)
	throw new IllegalArgumentException();
	fOffset= offset;
	fLength= length;
	fText= text;
	fOwner= owner;
	}

	/**
	* Executes the document command on the specified document.
	*
	* @param document the document on which to execute the command.
	* @throws BadLocationException in case this commands cannot be executed
	*/
	public void execute(IDocument document) throws BadLocationException {

	if (fLength == 0 && fText == null)
	return;

	if (fOwner != null)
	document.removeDocumentListener(fOwner);

	document.replace(fOffset, fLength, fText);

	if (fOwner != null)
	document.addDocumentListener(fOwner);
	}

	@Override
	public int compareTo(Command object) {
	if (isEqual(object))
	return 0;

	Command command= object;

	// diff middle points if not intersecting
	if (fOffset + fLength <= command.fOffset \|\| command.fOffset + command.fLength <= fOffset) {
	int value= (2 * fOffset + fLength) - (2 * command.fOffset + command.fLength);
	if (value != 0)
	return value;
	}
	// the answer
	return 42;
	}

	private boolean isEqual(Object object) {
	if (object == this)
	return true;
	if (!(object instanceof Command))
	return false;
	final Command command= (Command) object;
	return command.fOffset == fOffset && command.fLength == fLength;
	}
	}

	/**
	* An iterator, which iterates in reverse over a list.
	*
	* @param <E> the type of elements returned by this iterator
	*/
	private static class ReverseListIterator<E> implements Iterator<E> {

	/** The list iterator. */
	private final ListIterator<E> fListIterator;

	/**
	* Creates a reverse list iterator.
	* @param listIterator the iterator that this reverse iterator is based upon
	*/
	public ReverseListIterator(ListIterator<E> listIterator) {
	if (listIterator == null)
	throw new IllegalArgumentException();
	fListIterator= listIterator;
	}

	@Override
	public boolean hasNext() {
	return fListIterator.hasPrevious();
	}

	@Override
	public E next() {
	return fListIterator.previous();
	}

	@Override
	public void remove() {
	throw new UnsupportedOperationException();
	}
	}

	/**
	* A command iterator.
	*/
	private static class CommandIterator implements Iterator<Command> {

	/** The command iterator. */
	private final Iterator<Command> fIterator;

	/** The original command. */
	private Command fCommand;

	/** A flag indicating the direction of iteration. */
	private boolean fForward;

	/**
	* Creates a command iterator.
	*
	* @param commands an ascending ordered list of commands
	* @param command the original command
	* @param forward the direction
	*/
	public CommandIterator(final List<Command> commands, final Command command, final boolean forward) {
	if (commands == null \|\| command == null)
	throw new IllegalArgumentException();
	fIterator= forward ? commands.iterator() : new ReverseListIterator<>(commands.listIterator(commands.size()));
	fCommand= command;
	fForward= forward;
	}

	@Override
	public boolean hasNext() {
	return fCommand != null \|\| fIterator.hasNext();
	}

	@Override
	public Command next() {

	if (!hasNext())
	throw new NoSuchElementException();

	if (fCommand == null)
	return fIterator.next();

	if (!fIterator.hasNext()) {
	final Command tempCommand= fCommand;
	fCommand= null;
	return tempCommand;
	}

	final Command command= fIterator.next();
	final int compareValue= command.compareTo(fCommand);

	if ((compareValue < 0) ^ !fForward) {
	return command;

	} else if ((compareValue > 0) ^ !fForward) {
	final Command tempCommand= fCommand;
	fCommand= command;
	return tempCommand;

	} else {
	throw new IllegalArgumentException();
	}
	}

	@Override
	public void remove() {
	throw new UnsupportedOperationException();
	}
	}

	/** Must the command be updated */
	public boolean doit= false;
	/** The offset of the command. */
	public int offset;
	/** The length of the command */
	public int length;
	/** The text to be inserted */
	public String text;
	/**
	* The owner of the document command which will not be notified.
	* @since 2.1
	*/
	public IDocumentListener owner;
	/**
	* The caret offset with respect to the document before the document command is executed.
	* @since 2.1
	*/
	public int caretOffset;
	/**
	* Additional document commands.
	* @since 2.1
	*/
	private final List<Command> fCommands= new ArrayList<>();
	/**
	* Indicates whether the caret should be shifted by this command.
	* @since 3.0
	*/
	public boolean shiftsCaret;


	/**
	* Creates a new document command.
	*/
	protected DocumentCommand() {
	}

	/**
	* Translates a verify event into a document replace command using the given offset.
	*
	* @param event the event to be translated
	* @param modelRange the event range as model range
	*/
	void setEvent(VerifyEvent event, IRegion modelRange) {

	doit= true;
	text= event.text;

	offset= modelRange.getOffset();
	length= modelRange.getLength();

	owner= null;
	caretOffset= -1;
	shiftsCaret= true;
	fCommands.clear();
	}

	/**
	* Fills the given verify event with the replace text and the <code>doit</code>
	* flag of this document command. Returns whether the document command
	* covers the same range as the verify event considering the given offset.
	*
	* @param event the event to be changed
	* @param modelRange to be considered for range comparison
	* @return <code>true</code> if this command and the event cover the same range
	*/
	boolean fillEvent(VerifyEvent event, IRegion modelRange) {
	event.text= text;
	event.doit= (offset == modelRange.getOffset() && length == modelRange.getLength() && doit && caretOffset == -1);
	return event.doit;
	}

	/**
	* Adds an additional replace command. The added replace command must not overlap
	* with existing ones. If the document command owner is not <code>null</code>, it will not
	* get document change notifications for the particular command.
	*
	* @param commandOffset the offset of the region to replace
	* @param commandLength the length of the region to replace
	* @param commandText the text to replace with, may be <code>null</code>
	* @param commandOwner the command owner, may be <code>null</code>
	* @throws BadLocationException if the added command intersects with an existing one
	* @since 2.1
	*/
	public void addCommand(int commandOffset, int commandLength, String commandText, IDocumentListener commandOwner) throws BadLocationException {
	final Command command= new Command(commandOffset, commandLength, commandText, commandOwner);

	if (intersects(command))
	throw new BadLocationException();

	final int index= Collections.binarySearch(fCommands, command);

	// a command with exactly the same ranges exists already
	if (index >= 0)
	throw new BadLocationException();

	// binary search result is defined as (-(insertionIndex) - 1)
	final int insertionIndex= -(index + 1);

	// overlaps to the right?
	if (insertionIndex != fCommands.size() && intersects(fCommands.get(insertionIndex), command))
	throw new BadLocationException();

	// overlaps to the left?
	if (insertionIndex != 0 && intersects(fCommands.get(insertionIndex - 1), command))
	throw new BadLocationException();

	fCommands.add(insertionIndex, command);
	}

	/**
	* Returns an iterator over the commands in ascending position order.
	* The iterator includes the original document command.
	* Commands cannot be removed.
	*
	* @return returns the command iterator
	*/
	public Iterator<Command> getCommandIterator() {
	Command command= new Command(offset, length, text, owner);
	return new CommandIterator(fCommands, command, true);
	}

	/**
	* Returns the number of commands including the original document command.
	*
	* @return returns the number of commands
	* @since 2.1
	*/
	public int getCommandCount() {
	return 1 + fCommands.size();
	}

	/**
	* Returns whether the two given commands intersect.
	*
	* @param command0 the first command
	* @param command1 the second command
	* @return <code>true</code> if the commands intersect
	* @since 2.1
	*/
	private boolean intersects(Command command0, Command command1) {
	// diff middle points if not intersecting
	if (command0.fOffset + command0.fLength <= command1.fOffset \|\| command1.fOffset + command1.fLength <= command0.fOffset)
	return (2 * command0.fOffset + command0.fLength) - (2 * command1.fOffset + command1.fLength) == 0;
	return true;
	}

	/**
	* Returns whether the given command intersects with this command.
	*
	* @param command the command
	* @return <code>true</code> if the command intersects with this command
	* @since 2.1
	*/
	private boolean intersects(Command command) {
	// diff middle points if not intersecting
	if (offset + length <= command.fOffset \|\| command.fOffset + command.fLength <= offset)
	return (2 * offset + length) - (2 * command.fOffset + command.fLength) == 0;
	return true;
	}

	/**
	* Executes the document commands on a document.
	*
	* @param document the document on which to execute the commands
	* @throws BadLocationException in case access to the given document fails
	* @since 2.1
	*/
	void execute(IDocument document) throws BadLocationException {

	if (length == 0 && text == null && fCommands.size() == 0)
	return;

	DefaultPositionUpdater updater= new DefaultPositionUpdater(getCategory());
	Position caretPosition= null;
	try {
	if (updateCaret()) {
	document.addPositionCategory(getCategory());
	document.addPositionUpdater(updater);
	caretPosition= new Position(caretOffset);
	document.addPosition(getCategory(), caretPosition);
	}

	final Command originalCommand= new Command(offset, length, text, owner);
	for (final Iterator<Command> iterator= new CommandIterator(fCommands, originalCommand, false); iterator.hasNext(); )
	iterator.next().execute(document);

	} catch (BadLocationException e) {
	// ignore
	} catch (BadPositionCategoryException e) {
	// ignore
	} finally {
	if (updateCaret()) {
	document.removePositionUpdater(updater);
	try {
	document.removePositionCategory(getCategory());
	} catch (BadPositionCategoryException e) {
	Assert.isTrue(false);
	}
	caretOffset= caretPosition.getOffset();
	}
	}
	}

	/**
	* Returns <code>true</code> if the caret offset should be updated, <code>false</code> otherwise.
	*
	* @return <code>true</code> if the caret offset should be updated, <code>false</code> otherwise
	* @since 3.0
	*/
	private boolean updateCaret() {
	return shiftsCaret && caretOffset != -1;
	}

	/**
	* Returns the position category for the caret offset position.
	*
	* @return the position category for the caret offset position
	* @since 3.0
	*/
	private String getCategory() {
	return toString();
	}

	}