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/RSAKeyGenParameterSpec.java

/*
 * Copyright (c) 1999, 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;
import java.security.spec.AlgorithmParameterSpec;

/**
 * This class specifies the set of parameters used to generate an RSA
 * key pair.
 *
 * @author Jan Luehe
 *
 * @see java.security.KeyPairGenerator#initialize(java.security.spec.AlgorithmParameterSpec)
 *
 * @since 1.3
 */

public class RSAKeyGenParameterSpec implements AlgorithmParameterSpec {

    private int keysize;
    private BigInteger publicExponent;

    /**
     * The public-exponent value F0 = 3.
     */
    public static final BigInteger F0 = BigInteger.valueOf(3);

    /**
     * The public exponent-value F4 = 65537.
     */
    public static final BigInteger F4 = BigInteger.valueOf(65537);

    /**
     * Constructs a new {@code RSAParameterSpec} object from the
     * given keysize and public-exponent value.
     *
     * @param keysize the modulus size (specified in number of bits)
     * @param publicExponent the public exponent
     */
    public RSAKeyGenParameterSpec(int keysize, BigInteger publicExponent) {
        this.keysize = keysize;
        this.publicExponent = publicExponent;
    }

    /**
     * Returns the keysize.
     *
     * @return the keysize.
     */
    public int getKeysize() {
        return keysize;
    }

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

⏎ java/security/spec/RSAKeyGenParameterSpec.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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