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/PrivilegedAction.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;


/**
 * A computation to be performed with privileges enabled.  The computation is
 * performed by invoking {@code AccessController.doPrivileged} on the
 * {@code PrivilegedAction} object.  This interface is used only for
 * computations that do not throw checked exceptions; computations that
 * throw checked exceptions must use {@code PrivilegedExceptionAction}
 * instead.
 *
 * @see AccessController
 * @see AccessController#doPrivileged(PrivilegedAction)
 * @see PrivilegedExceptionAction
 */

public interface PrivilegedAction<T> {
    /**
     * Performs the computation.  This method will be called by
     * {@code AccessController.doPrivileged} after enabling privileges.
     *
     * @return a class-dependent value that may represent the results of the
     *         computation. Each class that implements
     *         {@code PrivilegedAction}
     *         should document what (if anything) this value represents.
     * @see AccessController#doPrivileged(PrivilegedAction)
     * @see AccessController#doPrivileged(PrivilegedAction,
     *                                     AccessControlContext)
     */
    T run();
}

⏎ java/security/PrivilegedAction.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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