Java tutorial
/* * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.text; /** * Represents a location within a document. It is intended to abstract away * implementation details of the document and enable specification of * positions within the document that are capable of tracking of change as * the document is edited. * <p> * A {@code Position} object points at a location between two characters. * As the surrounding content is altered, the {@code Position} object * adjusts its offset automatically to reflect the changes. If content is * inserted or removed before the {@code Position} object's location, then the * {@code Position} increments or decrements its offset, respectively, * so as to point to the same location. If a portion of the document is removed * that contains a {@code Position}'s offset, then the {@code Position}'s * offset becomes that of the beginning of the removed region. For example, if * a {@code Position} has an offset of 5 and the region 2-10 is removed, then * the {@code Position}'s offset becomes 2. * <p> * {@code Position} with an offset of 0 is a special case. It never changes its * offset while document content is altered. * * @author Timothy Prinzing */ public interface Position { /** * Fetches the current offset within the document. * * @return the offset >= 0 */ public int getOffset(); /** * A typesafe enumeration to indicate bias to a position * in the model. A position indicates a location between * two characters. The bias can be used to indicate an * interest toward one of the two sides of the position * in boundary conditions where a simple offset is * ambiguous. */ public static final class Bias { /** * Indicates to bias toward the next character * in the model. */ public static final Bias Forward = new Bias("Forward"); /** * Indicates a bias toward the previous character * in the model. */ public static final Bias Backward = new Bias("Backward"); /** * string representation */ public String toString() { return name; } private Bias(String name) { this.name = name; } private String name; } }