Java tutorial
/* * Copyright (c) 1997, 2017, 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.accessibility; /** * The {@code AccessibleValue} interface should be supported by any object that * supports a numerical value (e.g., a scroll bar). This interface provides the * standard mechanism for an assistive technology to determine and set the * numerical value as well as get the minimum and maximum values. Applications * can determine if an object supports the {@code AccessibleValue} interface by * first obtaining its {@code AccessibleContext} (see {@link Accessible}) and * then calling the {@link AccessibleContext#getAccessibleValue} method. If the * return value is not {@code null}, the object supports this interface. * * @author Peter Korn * @author Hans Muller * @author Willie Walker * @see Accessible * @see Accessible#getAccessibleContext * @see AccessibleContext * @see AccessibleContext#getAccessibleValue */ public interface AccessibleValue { /** * Get the value of this object as a {@code Number}. If the value has not * been set, the return value will be {@code null}. * * @return value of the object * @see #setCurrentAccessibleValue */ public Number getCurrentAccessibleValue(); /** * Set the value of this object as a {@code Number}. * * @param n the number to use for the value * @return {@code true} if the value was set; else {@code false} * @see #getCurrentAccessibleValue */ public boolean setCurrentAccessibleValue(Number n); // /** // * Get the description of the value of this object. // * // * @return description of the value of the object // */ // public String getAccessibleValueDescription(); /** * Get the minimum value of this object as a {@code Number}. * * @return minimum value of the object; {@code null} if this object does not * have a minimum value * @see #getMaximumAccessibleValue */ public Number getMinimumAccessibleValue(); /** * Get the maximum value of this object as a {@code Number}. * * @return maximum value of the object; {@code null} if this object does not * have a maximum value * @see #getMinimumAccessibleValue */ public Number getMaximumAccessibleValue(); }