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/security/sasl/AuthenticationException.java

/*
 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.security.sasl;

/**
 * This exception is thrown by a SASL mechanism implementation
 * to indicate that the SASL
 * exchange has failed due to reasons related to authentication, such as
 * an invalid identity, passphrase, or key.
 * <p>
 * Note that the lack of an AuthenticationException does not mean that
 * the failure was not due to an authentication error.  A SASL mechanism
 * implementation might throw the more general SaslException instead of
 * AuthenticationException if it is unable to determine the nature
 * of the failure, or if does not want to disclose the nature of
 * the failure, for example, due to security reasons.
 *
 * @since 1.5
 *
 * @author Rosanna Lee
 * @author Rob Weltman
 */
public class AuthenticationException extends SaslException {
    /**
     * Constructs a new instance of {@code AuthenticationException}.
     * The root exception and the detailed message are null.
     */
    public AuthenticationException () {
        super();
    }

    /**
     * Constructs a new instance of {@code AuthenticationException}
     * with a detailed message.
     * The root exception is null.
     * @param detail A possibly null string containing details of the exception.
     *
     * @see java.lang.Throwable#getMessage
     */
    public AuthenticationException (String detail) {
        super(detail);
    }

    /**
     * Constructs a new instance of {@code AuthenticationException} with a detailed message
     * and a root exception.
     *
     * @param detail A possibly null string containing details of the exception.
     * @param ex A possibly null root exception that caused this exception.
     *
     * @see java.lang.Throwable#getMessage
     * @see #getCause
     */
    public AuthenticationException (String detail, Throwable ex) {
        super(detail, ex);
    }

    /** Use serialVersionUID from JSR 28 RI for interoperability */
    private static final long serialVersionUID = -3579708765071815007L;
}

⏎ javax/security/sasl/AuthenticationException.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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