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/naming/spi/Resolver.java

/*
 * Copyright (c) 1999, 2004, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.naming.spi;

import javax.naming.Context;
import javax.naming.Name;
import javax.naming.NamingException;

/**
  * This interface represents an "intermediate context" for name resolution.
  *<p>
  * The Resolver interface contains methods that are implemented by contexts
  * that do not support subtypes of Context, but which can act as
  * intermediate contexts for resolution purposes.
  *<p>
  * A <tt>Name</tt> parameter passed to any method is owned
  * by the caller.  The service provider will not modify the object
  * or keep a reference to it.
  * A <tt>ResolveResult</tt> object returned by any
  * method is owned by the caller.  The caller may subsequently modify it;
  * the service provider may not.
  *
  * @author Rosanna Lee
  * @author Scott Seligman
  * @since 1.3
  */

public interface Resolver {

    /**
     * Partially resolves a name.  Stops at the first
     * context that is an instance of a given subtype of
     * <code>Context</code>.
     *
     * @param name
     *          the name to resolve
     * @param contextType
     *          the type of object to resolve.  This should
     *          be a subtype of <code>Context</code>.
     * @return  the object that was found, along with the unresolved
     *          suffix of <code>name</code>.  Cannot be null.
     *
     * @throws  javax.naming.NotContextException
     *          if no context of the appropriate type is found
     * @throws  NamingException if a naming exception was encountered
     *
     * @see #resolveToClass(String, Class)
     */
    public ResolveResult resolveToClass(Name name,
                                        Class<? extends Context> contextType)
            throws NamingException;

    /**
     * Partially resolves a name.
     * See {@link #resolveToClass(Name, Class)} for details.
     *
     * @param name
     *          the name to resolve
     * @param contextType
     *          the type of object to resolve.  This should
     *          be a subtype of <code>Context</code>.
     * @return  the object that was found, along with the unresolved
     *          suffix of <code>name</code>.  Cannot be null.
     *
     * @throws  javax.naming.NotContextException
     *          if no context of the appropriate type is found
     * @throws  NamingException if a naming exception was encountered
     */
    public ResolveResult resolveToClass(String name,
                                        Class<? extends Context> contextType)
            throws NamingException;
};

⏎ javax/naming/spi/Resolver.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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