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 com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ com/sun/imageio/plugins/gif/GIFStreamMetadataFormatResources.java

/*
 * Copyright (c) 2001, 2005, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package com.sun.imageio.plugins.gif;

import java.util.ListResourceBundle;

public class GIFStreamMetadataFormatResources extends ListResourceBundle {

    public GIFStreamMetadataFormatResources() {}

    protected Object[][] getContents() {
        return new Object[][] {

        // Node name, followed by description
        { "Version", "The file version, either 87a or 89a" },
        { "LogicalScreenDescriptor",
          "The logical screen descriptor, except for the global color table" },
        { "GlobalColorTable", "The global color table" },
        { "ColorTableEntry", "A global color table entry" },

        // Node name + "/" + AttributeName, followed by description
        { "Version/value",
          "The version string" },
        { "LogicalScreenDescriptor/logicalScreenWidth",
          "The width in pixels of the whole picture" },
        { "LogicalScreenDescriptor/logicalScreenHeight",
          "The height in pixels of the whole picture" },
        { "LogicalScreenDescriptor/colorResolution",
          "The number of bits of color resolution, beteen 1 and 8" },
        { "LogicalScreenDescriptor/pixelAspectRatio",
          "If 0, indicates square pixels, else W/H = (value + 15)/64" },
        { "GlobalColorTable/sizeOfGlobalColorTable",
          "The number of entries in the global color table" },
        { "GlobalColorTable/backgroundColorIndex",
          "The index of the color table entry to be used as a background" },
        { "GlobalColorTable/sortFlag",
          "True if the global color table is sorted by frequency" },
        { "ColorTableEntry/index", "The index of the color table entry" },
        { "ColorTableEntry/red",
          "The red value for the color table entry" },
        { "ColorTableEntry/green",
          "The green value for the color table entry" },
        { "ColorTableEntry/blue",
          "The blue value for the color table entry" },

        };
    }
}

⏎ com/sun/imageio/plugins/gif/GIFStreamMetadataFormatResources.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
Download 

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