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/print/attribute/URISyntax.java

/*
 * Copyright (c) 2000, 2004, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 *
 *
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 */


package javax.print.attribute;

import java.io.Serializable;
import java.net.URI;

/**
 * Class URISyntax is an abstract base class providing the common
 * implementation of all attributes whose value is a Uniform Resource
 * Identifier (URI). Once constructed, a URI attribute's value is immutable.
 * <P>
 *
 * @author  Alan Kaminsky
 */
public abstract class URISyntax implements Serializable, Cloneable {

    private static final long serialVersionUID = -7842661210486401678L;

    /**
     * URI value of this URI attribute.
     * @serial
     */
    private URI uri;

    /**
     * Constructs a URI attribute with the specified URI.
     *
     * @param  uri  URI.
     *
     * @exception  NullPointerException
     *     (unchecked exception) Thrown if <CODE>uri</CODE> is null.
     */
    protected URISyntax(URI uri) {
        this.uri = verify (uri);
    }

    private static URI verify(URI uri) {
        if (uri == null) {
            throw new NullPointerException(" uri is null");
        }
        return uri;
    }

    /**
     * Returns this URI attribute's URI value.
     * @return the URI.
     */
    public URI getURI()  {
        return uri;
    }

    /**
     * Returns a hashcode for this URI attribute.
     *
     * @return  A hashcode value for this object.
     */
    public int hashCode() {
        return uri.hashCode();
    }

    /**
     * Returns whether this URI attribute is equivalent to the passed in
     * object.
     * To be equivalent, all of the following conditions must be true:
     * <OL TYPE=1>
     * <LI>
     * <CODE>object</CODE> is not null.
     * <LI>
     * <CODE>object</CODE> is an instance of class URISyntax.
     * <LI>
     * This URI attribute's underlying URI and <CODE>object</CODE>'s
     * underlying URI are equal.
     * </OL>
     *
     * @param  object  Object to compare to.
     *
     * @return  True if <CODE>object</CODE> is equivalent to this URI
     *          attribute, false otherwise.
     */
    public boolean equals(Object object) {
        return(object != null &&
               object instanceof URISyntax &&
               this.uri.equals (((URISyntax) object).uri));
    }

    /**
     * Returns a String identifying this URI attribute. The String is the
     * string representation of the attribute's underlying URI.
     *
     * @return  A String identifying this object.
     */
    public String toString() {
        return uri.toString();
    }

}

⏎ javax/print/attribute/URISyntax.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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