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/StringValueExp.java

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

package javax.management;



/**
 * Represents strings that are arguments to relational constraints.
 * A <CODE>StringValueExp</CODE> may be used anywhere a <CODE>ValueExp</CODE> is required.
 *
 * @since 1.5
 */
public class StringValueExp implements ValueExp   {

    /* Serial version */
    private static final long serialVersionUID = -3256390509806284044L;

    /**
     * @serial The string literal
     */
    private String val;

    /**
     * Basic constructor.
     */
    public StringValueExp() {
    }

    /**
     * Creates a new <CODE>StringValueExp</CODE> representing the
     * given string.
     *
     * @param val the string that will be the value of this expression
     */
    public StringValueExp(String val) {
        this.val = val;
    }

    /**
     * Returns the string represented by the
     * <CODE>StringValueExp</CODE> instance.
     *
     * @return the string.
     */
    public String getValue()  {
        return val;
    }

    /**
     * Returns the string representing the object.
     */
    public String toString()  {
        return "'" + val.replace("'", "''") + "'";
    }


    /**
     * 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.
     */
    /* There is no need for this method, because if a query is being
       evaluated a StringValueExp can only appear inside a QueryExp,
       and that QueryExp will itself have done setMBeanServer.  */
    @Deprecated
    public void setMBeanServer(MBeanServer s)  { }

    /**
     * Applies the ValueExp on a MBean.
     *
     * @param name The name of the MBean on which the ValueExp will be applied.
     *
     * @return  The <CODE>ValueExp</CODE>.
     *
     * @exception BadStringOperationException
     * @exception BadBinaryOpValueExpException
     * @exception BadAttributeValueExpException
     * @exception InvalidApplicationException
     */
    public ValueExp apply(ObjectName name) throws BadStringOperationException, BadBinaryOpValueExpException,
        BadAttributeValueExpException, InvalidApplicationException  {
        return this;
    }
 }

⏎ javax/management/StringValueExp.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

⇑ Download and Use JDK 8

⇑⇑ FAQ for JDK (Java Development Kit)