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/lang/model/element/AnnotationValue.java

/*
 * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.lang.model.element;

/**
 * Represents a value of an annotation type element.
 * A value is of one of the following types:
 * <ul><li> a wrapper class (such as {@link Integer}) for a primitive type
 *     <li> {@code String}
 *     <li> {@code TypeMirror}
 *     <li> {@code VariableElement} (representing an enum constant)
 *     <li> {@code AnnotationMirror}
 *     <li> {@code List<? extends AnnotationValue>}
 *              (representing the elements, in declared order, if the value is an array)
 * </ul>
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @since 1.6
 */
public interface AnnotationValue {

    /**
     * Returns the value.
     *
     * @return the value
     */
    Object getValue();

    /**
     * Returns a string representation of this value.
     * This is returned in a form suitable for representing this value
     * in the source code of an annotation.
     *
     * @return a string representation of this value
     */
    String toString();

    /**
     * Applies a visitor to this value.
     *
     * @param <R> the return type of the visitor's methods
     * @param <P> the type of the additional parameter to the visitor's methods
     * @param v   the visitor operating on this value
     * @param p   additional parameter to the visitor
     * @return a visitor-specified result
     */
    <R, P> R accept(AnnotationValueVisitor<R, P> v, P p);
}

⏎ javax/lang/model/element/AnnotationValue.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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