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/Name.java

/*
 * Copyright (c) 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;

/**
 * An immutable sequence of characters.  When created by the same
 * implementation, objects implementing this interface must obey the
 * general {@linkplain Object#equals equals contract} when compared
 * with each other.  Therefore, {@code Name} objects from the same
 * implementation are usable in collections while {@code Name}s from
 * different implementations may not work properly in collections.
 *
 * <p>An empty {@code Name} has a length of zero.
 *
 * <p>In the context of {@linkplain
 * javax.annotation.processing.ProcessingEnvironment annotation
 * processing}, the guarantees for "the same" implementation must
 * include contexts where the {@linkplain javax.annotation.processing
 * API mediated} side effects of {@linkplain
 * javax.annotation.processing.Processor processors} could be visible
 * to each other, including successive annotation processing
 * {@linkplain javax.annotation.processing.RoundEnvironment rounds}.
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @see javax.lang.model.util.Elements#getName
 * @since 1.6
 */
public interface Name extends CharSequence {
    /**
     * Returns {@code true} if the argument represents the same
     * name as {@code this}, and {@code false} otherwise.
     *
     * <p>Note that the identity of a {@code Name} is a function both
     * of its content in terms of a sequence of characters as well as
     * the implementation which created it.
     *
     * @param obj  the object to be compared with this element
     * @return {@code true} if the specified object represents the same
     *          name as this
     * @see Element#equals
     */
    boolean equals(Object obj);

    /**
     * Obeys the general contract of {@link Object#hashCode Object.hashCode}.
     *
     * @see #equals
     */
    int hashCode();

    /**
     * Compares this name to the specified {@code CharSequence}. The result
     * is {@code true} if and only if this name represents the same sequence
     * of {@code char} values as the specified sequence.
     *
     * @return {@code true} if this name represents the same sequence
     * of {@code char} values as the specified sequence, {@code false}
     * otherwise
     *
     * @param cs The sequence to compare this name against
     * @see String#contentEquals(CharSequence)
     */
    boolean contentEquals(CharSequence cs);
}

⏎ javax/lang/model/element/Name.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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