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/management/QueryExp.java

/*
 * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.management;

// java import
import java.io.Serializable;


/**
 * <p>Represents relational constraints similar to database query "where
 * clauses". Instances of QueryExp are returned by the static methods of the
 * {@link Query} class.</p>
 *
 * <p>It is possible, but not
 * recommended, to create custom queries by implementing this
 * interface.  In that case, it is better to extend the {@link
 * QueryEval} class than to implement the interface directly, so that
 * the {@link #setMBeanServer} method works correctly.
 *
 * @see MBeanServer#queryNames MBeanServer.queryNames
 * @since 1.5
 */
public interface QueryExp extends Serializable {


     /**
      * Applies the QueryExp on an MBean.
      *
      * @param name The name of the MBean on which the QueryExp will be applied.
      *
      * @return  True if the query was successfully applied to the MBean, false otherwise
      *
      * @exception BadStringOperationException
      * @exception BadBinaryOpValueExpException
      * @exception BadAttributeValueExpException
      * @exception InvalidApplicationException
      */
     public boolean apply(ObjectName name) throws BadStringOperationException, BadBinaryOpValueExpException,
         BadAttributeValueExpException, InvalidApplicationException ;

     /**
      * Sets the MBean server on which the query is to be performed.
      *
      * @param s The MBean server on which the query is to be performed.
      */
     public void setMBeanServer(MBeanServer s) ;

 }

⏎ javax/management/QueryExp.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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