JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the javax.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ javax/accessibility/AccessibleValue.java

/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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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();
}

⏎ javax/accessibility/AccessibleValue.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - org.* Package Source Code

⇐ JRE 8 rt.jar - java.* Package Source Code

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