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/annotation/processing/RoundEnvironment.java

/*
 * Copyright (c) 2005, 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.annotation.processing;

import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import java.util.Set;
import java.lang.annotation.Annotation;

/**
 * An annotation processing tool framework will {@linkplain
 * Processor#process provide an annotation processor with an object
 * implementing this interface} so that the processor can query for
 * information about a round of annotation processing.
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ahé
 * @since 1.6
 */
public interface RoundEnvironment {
    /**
     * Returns {@code true} if types generated by this round will not
     * be subject to a subsequent round of annotation processing;
     * returns {@code false} otherwise.
     *
     * @return {@code true} if types generated by this round will not
     * be subject to a subsequent round of annotation processing;
     * returns {@code false} otherwise
     */
    boolean processingOver();

    /**
     * Returns {@code true} if an error was raised in the prior round
     * of processing; returns {@code false} otherwise.
     *
     * @return {@code true} if an error was raised in the prior round
     * of processing; returns {@code false} otherwise
     */
    boolean errorRaised();

    /**
     * Returns the root elements for annotation processing generated
     * by the prior round.
     *
     * @return the root elements for annotation processing generated
     * by the prior round, or an empty set if there were none
     */
    Set<? extends Element> getRootElements();

    /**
     * Returns the elements annotated with the given annotation type.
     * The annotation may appear directly or be inherited.  Only
     * package elements and type elements <i>included</i> in this
     * round of annotation processing, or declarations of members,
     * constructors, parameters, or type parameters declared within
     * those, are returned.  Included type elements are {@linkplain
     * #getRootElements root types} and any member types nested within
     * them.  Elements in a package are not considered included simply
     * because a {@code package-info} file for that package was
     * created.
     *
     * @param a  annotation type being requested
     * @return the elements annotated with the given annotation type,
     * or an empty set if there are none
     * @throws IllegalArgumentException if the argument does not
     * represent an annotation type
     */
    Set<? extends Element> getElementsAnnotatedWith(TypeElement a);

    /**
     * Returns the elements annotated with the given annotation type.
     * The annotation may appear directly or be inherited.  Only
     * package elements and type elements <i>included</i> in this
     * round of annotation processing, or declarations of members,
     * constructors, parameters, or type parameters declared within
     * those, are returned.  Included type elements are {@linkplain
     * #getRootElements root types} and any member types nested within
     * them.  Elements in a package are not considered included simply
     * because a {@code package-info} file for that package was
     * created.
     *
     * @param a  annotation type being requested
     * @return the elements annotated with the given annotation type,
     * or an empty set if there are none
     * @throws IllegalArgumentException if the argument does not
     * represent an annotation type
     */
    Set<? extends Element> getElementsAnnotatedWith(Class<? extends Annotation> a);
}

⏎ javax/annotation/processing/RoundEnvironment.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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