| /******************************************************************************* |
| * Copyright (c) 2005, 2011 Oracle. 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: |
| * Oracle - initial API and implementation |
| ******************************************************************************/ |
| package org.eclipse.jpt.common.core.utility; |
| |
| import org.eclipse.jpt.common.utility.internal.StringTools; |
| import org.eclipse.wst.validation.internal.provisional.core.IMessage; |
| |
| /** |
| * A text range defines the offset into, length of, and line of a piece |
| * of text. |
| * <p> |
| * Provisional API: This interface is part of an interim API that is still |
| * under development and expected to change significantly before reaching |
| * stability. It is 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. |
| * <p> |
| * This interface is not intended to be implemented by clients. |
| * |
| * @version 2.0 |
| * @since 2.0 |
| */ |
| public interface TextRange { |
| |
| /** |
| * Return the offset of the text. |
| */ |
| int getOffset(); |
| |
| /** |
| * Return the length of the text. |
| */ |
| int getLength(); |
| |
| /** |
| * Return whether the range includes the character at the specified index. |
| */ |
| boolean includes(int index); |
| |
| /** |
| * Return whether the range touches an insertion cursor at the |
| * specified index. |
| */ |
| boolean touches(int index); |
| |
| /** |
| * Return the line number of the text. |
| */ |
| int getLineNumber(); |
| |
| /** |
| * Build and return a new text range for the specified values if they differ |
| * from the text range. If the specified values match the |
| * text range, simply return the text range unchanged. |
| */ |
| TextRange buildTextRange(int offset, int length, int lineNumber); |
| |
| /** |
| * Return whether the offsets, lengths, and line numbers are the same. |
| */ |
| boolean equals(Object obj); |
| |
| /** |
| * Return a hash code that corresponds to the {@link Object#equals(Object)} |
| * contract. |
| */ |
| int hashCode(); |
| |
| |
| /** |
| * Empty implementation of text range. |
| */ |
| final class Empty extends AbstractTextRange { |
| public static final TextRange INSTANCE = new Empty(); |
| public static TextRange instance() { |
| return INSTANCE; |
| } |
| // ensure single instance |
| private Empty() { |
| super(); |
| } |
| public int getLineNumber() { |
| return IMessage.LINENO_UNSET; |
| } |
| public int getOffset() { |
| return IMessage.OFFSET_UNSET; |
| } |
| public int getLength() { |
| return IMessage.OFFSET_UNSET; |
| } |
| @Override |
| public String toString() { |
| return StringTools.buildSingletonToString(this); |
| } |
| } |
| } |