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/cert/CertSelector.java

/*
 * Copyright (c) 2000, 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.cert;

/**
 * A selector that defines a set of criteria for selecting
 * {@code Certificate}s. Classes that implement this interface
 * are often used to specify which {@code Certificate}s should
 * be retrieved from a {@code CertStore}.
 * <p>
 * <b>Concurrent Access</b>
 * <p>
 * Unless otherwise specified, the methods defined in this interface are not
 * thread-safe. Multiple threads that need to access a single
 * object concurrently should synchronize amongst themselves and
 * provide the necessary locking. Multiple threads each manipulating
 * separate objects need not synchronize.
 *
 * @see Certificate
 * @see CertStore
 * @see CertStore#getCertificates
 *
 * @author      Steve Hanna
 * @since       1.4
 */
public interface CertSelector extends Cloneable {

    /**
     * Decides whether a {@code Certificate} should be selected.
     *
     * @param   cert    the {@code Certificate} to be checked
     * @return  {@code true} if the {@code Certificate}
     * should be selected, {@code false} otherwise
     */
    boolean match(Certificate cert);

    /**
     * Makes a copy of this {@code CertSelector}. Changes to the
     * copy will not affect the original and vice versa.
     *
     * @return a copy of this {@code CertSelector}
     */
    Object clone();
}

⏎ java/security/cert/CertSelector.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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