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/GetORBPropertiesFileAction.java

/*
 * Copyright (c) 1999, 2001, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 */

/*
 * (C) Copyright IBM Corp. 1993 - 1997 - All Rights Reserved
 *
 * The original version of this source code and documentation is
 * copyrighted and owned by IBM, Inc. These materials are provided under
 * terms of a License Agreement between IBM and Sun. This technology is
 * protected by multiple US and International patents. This notice and
 * attribution to IBM may not be removed.
 *
 */


package javax.rmi.CORBA;

import java.io.IOException;
import java.io.File;
import java.io.FileInputStream;

import java.security.AccessController;
import java.security.PrivilegedAction;
import sun.security.action.GetPropertyAction;
import java.util.Properties;

class GetORBPropertiesFileAction implements PrivilegedAction {
    private boolean debug = false ;

    public GetORBPropertiesFileAction () {
    }

    private String getSystemProperty(final String name) {
        // This will not throw a SecurityException because this
        // class was loaded from rt.jar using the bootstrap classloader.
        String propValue = (String) AccessController.doPrivileged(
            new PrivilegedAction() {
                public java.lang.Object run() {
                    return System.getProperty(name);
                }
            }
        );

        return propValue;
    }

    private void getPropertiesFromFile( Properties props, String fileName )
    {
        try {
            File file = new File( fileName ) ;
            if (!file.exists())
                return ;

            FileInputStream in = new FileInputStream( file ) ;

            try {
                props.load( in ) ;
            } finally {
                in.close() ;
            }
        } catch (Exception exc) {
            if (debug)
                System.out.println( "ORB properties file " + fileName +
                    " not found: " + exc) ;
        }
    }

    public Object run()
    {
        Properties defaults = new Properties() ;

        String javaHome = getSystemProperty( "java.home" ) ;
        String fileName = javaHome + File.separator + "lib" + File.separator +
            "orb.properties" ;

        getPropertiesFromFile( defaults, fileName ) ;

        Properties results = new Properties( defaults ) ;

        String userHome = getSystemProperty( "user.home" ) ;
        fileName = userHome + File.separator + "orb.properties" ;

        getPropertiesFromFile( results, fileName ) ;
        return results ;
    }
}

⏎ javax/rmi/CORBA/GetORBPropertiesFileAction.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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