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/ECParameterSpec.java

/*
 * Copyright (c) 2003, 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 immutable class specifies the set of domain parameters
 * used with elliptic curve cryptography (ECC).
 *
 * @see AlgorithmParameterSpec
 *
 * @author Valerie Peng
 *
 * @since 1.5
 */
public class ECParameterSpec implements AlgorithmParameterSpec {

    private final EllipticCurve curve;
    private final ECPoint g;
    private final BigInteger n;
    private final int h;

    /**
     * Creates elliptic curve domain parameters based on the
     * specified values.
     * @param curve the elliptic curve which this parameter
     * defines.
     * @param g the generator which is also known as the base point.
     * @param n the order of the generator {@code g}.
     * @param h the cofactor.
     * @exception NullPointerException if {@code curve},
     * {@code g}, or {@code n} is null.
     * @exception IllegalArgumentException if {@code n}
     * or {@code h} is not positive.
     */
    public ECParameterSpec(EllipticCurve curve, ECPoint g,
                           BigInteger n, int h) {
        if (curve == null) {
            throw new NullPointerException("curve is null");
        }
        if (g == null) {
            throw new NullPointerException("g is null");
        }
        if (n == null) {
            throw new NullPointerException("n is null");
        }
        if (n.signum() != 1) {
            throw new IllegalArgumentException("n is not positive");
        }
        if (h <= 0) {
            throw new IllegalArgumentException("h is not positive");
        }
        this.curve = curve;
        this.g = g;
        this.n = n;
        this.h = h;
    }

    /**
     * Returns the elliptic curve that this parameter defines.
     * @return the elliptic curve that this parameter defines.
     */
    public EllipticCurve getCurve() {
        return curve;
    }

    /**
     * Returns the generator which is also known as the base point.
     * @return the generator which is also known as the base point.
     */
    public ECPoint getGenerator() {
        return g;
    }

    /**
     * Returns the order of the generator.
     * @return the order of the generator.
     */
    public BigInteger getOrder() {
        return n;
    }

    /**
     * Returns the cofactor.
     * @return the cofactor.
     */
    public int getCofactor() {
        return h;
    }
}

⏎ java/security/spec/ECParameterSpec.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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