AccessibleValue.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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package javax.accessibility;

/**
 * The 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 AccessibleValue interface by first
 * obtaining its AccessibleContext (see
 * {@link Accessible}) and then calling the
 * {@link AccessibleContext#getAccessibleValue} method.
 * If the return value is not null, the object supports this interface.
 *
 * @see Accessible
 * @see Accessible#getAccessibleContext
 * @see AccessibleContext
 * @see AccessibleContext#getAccessibleValue
 *
 * @author      Peter Korn
 * @author      Hans Muller
 * @author      Willie Walker
 */
public interface AccessibleValue {

    /**
     * Get the value of this object as a Number.  If the value has not been
     * set, the return value will be null.
     *
     * @return value of the object
     * @see #setCurrentAccessibleValue
     */
    public Number getCurrentAccessibleValue();

    /**
     * Set the value of this object as a Number.
     *
     * @param n the number to use for the value
     * @return True if the value was set; else 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 Number.
     *
     * @return Minimum value of the object; null if this object does not
     * have a minimum value
     * @see #getMaximumAccessibleValue
     */
    public Number getMinimumAccessibleValue();

    /**
     * Get the maximum value of this object as a Number.
     *
     * @return Maximum value of the object; null if this object does not
     * have a maximum value
     * @see #getMinimumAccessibleValue
     */
    public Number getMaximumAccessibleValue();
}