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/AlgorithmConstraints.java

/*
 * Copyright (c) 2010, 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.Set;

/**
 * This interface specifies constraints for cryptographic algorithms,
 * keys (key sizes), and other algorithm parameters.
 * <p>
 * {@code AlgorithmConstraints} objects are immutable.  An implementation
 * of this interface should not provide methods that can change the state
 * of an instance once it has been created.
 * <p>
 * Note that {@code AlgorithmConstraints} can be used to represent the
 * restrictions described by the security properties
 * {@code jdk.certpath.disabledAlgorithms} and
 * {@code jdk.tls.disabledAlgorithms}, or could be used by a
 * concrete {@code PKIXCertPathChecker} to check whether a specified
 * certificate in the certification path contains the required algorithm
 * constraints.
 *
 * @see javax.net.ssl.SSLParameters#getAlgorithmConstraints
 * @see javax.net.ssl.SSLParameters#setAlgorithmConstraints(AlgorithmConstraints)
 *
 * @since 1.7
 */

public interface AlgorithmConstraints {

    /**
     * Determines whether an algorithm is granted permission for the
     * specified cryptographic primitives.
     *
     * @param primitives a set of cryptographic primitives
     * @param algorithm the algorithm name
     * @param parameters the algorithm parameters, or null if no additional
     *     parameters
     *
     * @return true if the algorithm is permitted and can be used for all
     *     of the specified cryptographic primitives
     *
     * @throws IllegalArgumentException if primitives or algorithm is null
     *     or empty
     */
    public boolean permits(Set<CryptoPrimitive> primitives,
            String algorithm, AlgorithmParameters parameters);

    /**
     * Determines whether a key is granted permission for the specified
     * cryptographic primitives.
     * <p>
     * This method is usually used to check key size and key usage.
     *
     * @param primitives a set of cryptographic primitives
     * @param key the key
     *
     * @return true if the key can be used for all of the specified
     *     cryptographic primitives
     *
     * @throws IllegalArgumentException if primitives is null or empty,
     *     or the key is null
     */
    public boolean permits(Set<CryptoPrimitive> primitives, Key key);

    /**
     * Determines whether an algorithm and the corresponding key are granted
     * permission for the specified cryptographic primitives.
     *
     * @param primitives a set of cryptographic primitives
     * @param algorithm the algorithm name
     * @param key the key
     * @param parameters the algorithm parameters, or null if no additional
     *     parameters
     *
     * @return true if the key and the algorithm can be used for all of the
     *     specified cryptographic primitives
     *
     * @throws IllegalArgumentException if primitives or algorithm is null
     *     or empty, or the key is null
     */
    public boolean permits(Set<CryptoPrimitive> primitives,
                String algorithm, Key key, AlgorithmParameters parameters);

}

⏎ java/security/AlgorithmConstraints.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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