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/AnnotationMirror.java

/*
 * Copyright (c) 2005, 2006, 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;

import java.util.Map;
import javax.lang.model.type.DeclaredType;

/**
 * Represents an annotation.  An annotation associates a value with
 * each element of an annotation type.
 *
 * <p> Annotations should be compared using the {@code equals}
 * method.  There is no guarantee that any particular annotation will
 * always be represented by the same object.
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @since 1.6
 */
public interface AnnotationMirror {

    /**
     * Returns the type of this annotation.
     *
     * @return the type of this annotation
     */
    DeclaredType getAnnotationType();

    /**
     * Returns the values of this annotation's elements.
     * This is returned in the form of a map that associates elements
     * with their corresponding values.
     * Only those elements with values explicitly present in the
     * annotation are included, not those that are implicitly assuming
     * their default values.
     * The order of the map matches the order in which the
     * values appear in the annotation's source.
     *
     * <p>Note that an annotation mirror of a marker annotation type
     * will by definition have an empty map.
     *
     * <p>To fill in default values, use {@link
     * javax.lang.model.util.Elements#getElementValuesWithDefaults
     * getElementValuesWithDefaults}.
     *
     * @return the values of this annotation's elements,
     *          or an empty map if there are none
     */
    Map<? extends ExecutableElement, ? extends AnnotationValue> getElementValues();
}

⏎ javax/lang/model/element/AnnotationMirror.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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