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 java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/security/KeyPair.java

/*
 * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.security;

import java.util.*;

/**
 * This class is a simple holder for a key pair (a public key and a
 * private key). It does not enforce any security, and, when initialized,
 * should be treated like a PrivateKey.
 *
 * @see PublicKey
 * @see PrivateKey
 *
 * @author Benjamin Renaud
 */

public final class KeyPair implements java.io.Serializable {

    private static final long serialVersionUID = -7565189502268009837L;

    private PrivateKey privateKey;
    private PublicKey publicKey;

    /**
     * Constructs a key pair from the given public key and private key.
     *
     * <p>Note that this constructor only stores references to the public
     * and private key components in the generated key pair. This is safe,
     * because {@code Key} objects are immutable.
     *
     * @param publicKey the public key.
     *
     * @param privateKey the private key.
     */
    public KeyPair(PublicKey publicKey, PrivateKey privateKey) {
        this.publicKey = publicKey;
        this.privateKey = privateKey;
    }

    /**
     * Returns a reference to the public key component of this key pair.
     *
     * @return a reference to the public key.
     */
    public PublicKey getPublic() {
        return publicKey;
    }

     /**
     * Returns a reference to the private key component of this key pair.
     *
     * @return a reference to the private key.
     */
   public PrivateKey getPrivate() {
        return privateKey;
    }
}

⏎ java/security/KeyPair.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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