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/spec/RSAPrivateCrtKeySpec.java

/*
 * Copyright (c) 1998, 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.spec;

import java.math.BigInteger;

/**
 * This class specifies an RSA private key, as defined in the PKCS#1
 * standard, using the Chinese Remainder Theorem (CRT) information values for
 * efficiency.
 *
 * @author Jan Luehe
 *
 *
 * @see java.security.Key
 * @see java.security.KeyFactory
 * @see KeySpec
 * @see PKCS8EncodedKeySpec
 * @see RSAPrivateKeySpec
 * @see RSAPublicKeySpec
 */

public class RSAPrivateCrtKeySpec extends RSAPrivateKeySpec {

    private final BigInteger publicExponent;
    private final BigInteger primeP;
    private final BigInteger primeQ;
    private final BigInteger primeExponentP;
    private final BigInteger primeExponentQ;
    private final BigInteger crtCoefficient;



   /**
    * Creates a new {@code RSAPrivateCrtKeySpec}
    * given the modulus, publicExponent, privateExponent,
    * primeP, primeQ, primeExponentP, primeExponentQ, and
    * crtCoefficient as defined in PKCS#1.
    *
    * @param modulus the modulus n
    * @param publicExponent the public exponent e
    * @param privateExponent the private exponent d
    * @param primeP the prime factor p of n
    * @param primeQ the prime factor q of n
    * @param primeExponentP this is d mod (p-1)
    * @param primeExponentQ this is d mod (q-1)
    * @param crtCoefficient the Chinese Remainder Theorem
    * coefficient q-1 mod p
    */
    public RSAPrivateCrtKeySpec(BigInteger modulus,
                                BigInteger publicExponent,
                                BigInteger privateExponent,
                                BigInteger primeP,
                                BigInteger primeQ,
                                BigInteger primeExponentP,
                                BigInteger primeExponentQ,
                                BigInteger crtCoefficient) {
        super(modulus, privateExponent);
        this.publicExponent = publicExponent;
        this.primeP = primeP;
        this.primeQ = primeQ;
        this.primeExponentP = primeExponentP;
        this.primeExponentQ = primeExponentQ;
        this.crtCoefficient = crtCoefficient;
    }

    /**
     * Returns the public exponent.
     *
     * @return the public exponent
     */
    public BigInteger getPublicExponent() {
        return this.publicExponent;
    }

    /**
     * Returns the primeP.

     * @return the primeP
     */
    public BigInteger getPrimeP() {
        return this.primeP;
    }

    /**
     * Returns the primeQ.
     *
     * @return the primeQ
     */
    public BigInteger getPrimeQ() {
        return this.primeQ;
    }

    /**
     * Returns the primeExponentP.
     *
     * @return the primeExponentP
     */
    public BigInteger getPrimeExponentP() {
        return this.primeExponentP;
    }

    /**
     * Returns the primeExponentQ.
     *
     * @return the primeExponentQ
     */
    public BigInteger getPrimeExponentQ() {
        return this.primeExponentQ;
    }

    /**
     * Returns the crtCoefficient.
     *
     * @return the crtCoefficient
     */
    public BigInteger getCrtCoefficient() {
        return this.crtCoefficient;
    }
}

⏎ java/security/spec/RSAPrivateCrtKeySpec.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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