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/rmi/CORBA/ValueHandlerMultiFormat.java

/*
 * Copyright (c) 2002, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.rmi.CORBA;

/**
 * Java to IDL ptc 02-01-12 1.5.1.5
 * @since 1.5
 */
public interface ValueHandlerMultiFormat extends ValueHandler {

    /**
     * Returns the maximum stream format version for
     * RMI/IDL custom value types that is supported
     * by this ValueHandler object. The ValueHandler
     * object must support the returned stream format version and
     * all lower versions.
     *
     * An ORB may use this value to include in a standard
     * IOR tagged component or service context to indicate to other
     * ORBs the maximum RMI-IIOP stream format that it
     * supports.  If not included, the default for GIOP 1.2
     * is stream format version 1, and stream format version
     * 2 for GIOP 1.3 and higher.
     */
    byte getMaximumStreamFormatVersion();

    /**
     * Allows the ORB to pass the stream format
     * version for RMI/IDL custom value types. If the ORB
     * calls this method, it must pass a stream format version
     * between 1 and the value returned by the
     * getMaximumStreamFormatVersion method inclusive,
     * or else a BAD_PARAM exception with standard minor code
     * will be thrown.
     *
     * If the ORB calls the older ValueHandler.writeValue(OutputStream,
     * Serializable) method, stream format version 1 is implied.
     *
     * The ORB output stream passed to the ValueHandlerMultiFormat.writeValue
     * method must implement the ValueOutputStream interface, and the
     * ORB input stream passed to the ValueHandler.readValue method must
     * implement the ValueInputStream interface.
     */
    void writeValue(org.omg.CORBA.portable.OutputStream out,
                    java.io.Serializable value,
                    byte streamFormatVersion);
}

⏎ javax/rmi/CORBA/ValueHandlerMultiFormat.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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