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/lang/reflect/Member.java

/*
 * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.lang.reflect;

/**
 * Member is an interface that reflects identifying information about
 * a single member (a field or a method) or a constructor.
 *
 * @see java.lang.Class
 * @see Field
 * @see Method
 * @see Constructor
 *
 * @author Nakul Saraiya
 */
public
interface Member {

    /**
     * Identifies the set of all public members of a class or interface,
     * including inherited members.
     */
    public static final int PUBLIC = 0;

    /**
     * Identifies the set of declared members of a class or interface.
     * Inherited members are not included.
     */
    public static final int DECLARED = 1;

    /**
     * Returns the Class object representing the class or interface
     * that declares the member or constructor represented by this Member.
     *
     * @return an object representing the declaring class of the
     * underlying member
     */
    public Class<?> getDeclaringClass();

    /**
     * Returns the simple name of the underlying member or constructor
     * represented by this Member.
     *
     * @return the simple name of the underlying member
     */
    public String getName();

    /**
     * Returns the Java language modifiers for the member or
     * constructor represented by this Member, as an integer.  The
     * Modifier class should be used to decode the modifiers in
     * the integer.
     *
     * @return the Java language modifiers for the underlying member
     * @see Modifier
     */
    public int getModifiers();

    /**
     * Returns {@code true} if this member was introduced by
     * the compiler; returns {@code false} otherwise.
     *
     * @return true if and only if this member was introduced by
     * the compiler.
     * @jls 13.1 The Form of a Binary
     * @since 1.5
     */
    public boolean isSynthetic();
}

⏎ java/lang/reflect/Member.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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