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/GenericArrayType.java

/*
 * Copyright (c) 2003, 2004, 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;

/**
 * {@code GenericArrayType} represents an array type whose component
 * type is either a parameterized type or a type variable.
 * @since 1.5
 */
public interface GenericArrayType extends Type {
    /**
     * Returns a {@code Type} object representing the component type
     * of this array. This method creates the component type of the
     * array.  See the declaration of {@link
     * java.lang.reflect.ParameterizedType ParameterizedType} for the
     * semantics of the creation process for parameterized types and
     * see {@link java.lang.reflect.TypeVariable TypeVariable} for the
     * creation process for type variables.
     *
     * @return  a {@code Type} object representing the component type
     *     of this array
     * @throws TypeNotPresentException if the underlying array type's
     *     component type refers to a non-existent type declaration
     * @throws MalformedParameterizedTypeException if  the
     *     underlying array type's component type refers to a
     *     parameterized type that cannot be instantiated for any reason
     */
    Type getGenericComponentType();
}

⏎ java/lang/reflect/GenericArrayType.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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