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 org.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ org/omg/CORBA/Principal.java

/*
 * Copyright (c) 1997, 2004, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package org.omg.CORBA;


/**
 * A class that contains information about the identity of
 * the client, for access control
 * and other purposes. It contains a single attribute, the name of the
 * <code>Principal</code>, encoded as a sequence of bytes.
 * <P>
 * @deprecated Deprecated by CORBA 2.2.
 */
@Deprecated
public class Principal {
    /**
     * Sets the name of this <code>Principal</code> object to the given value.
     * @param value the value to be set in the <code>Principal</code>
     * @deprecated Deprecated by CORBA 2.2.
     */
    @Deprecated
    public void name(byte[] value) {
        throw new org.omg.CORBA.NO_IMPLEMENT() ;
    }

    /**
     * Gets the name of this <code>Principal</code> object.
     * @return the name of this <code>Principal</code> object
     * @deprecated Deprecated by CORBA 2.2.
     */
    @Deprecated
    public byte[] name() {
        throw new org.omg.CORBA.NO_IMPLEMENT() ;
    }
}

⏎ org/omg/CORBA/Principal.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - com.* Package Source Code

⇐ JRE 8 rt.jar - javax.* Package Source Code

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