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/GIFImageWriterSpi.java

/*
 * Copyright (c) 2005, 2010, 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.awt.image.ColorModel;
import java.awt.image.SampleModel;
import java.util.Locale;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.ImageWriter;
import javax.imageio.spi.ImageWriterSpi;
import javax.imageio.stream.ImageOutputStream;
import com.sun.imageio.plugins.common.PaletteBuilder;

public class GIFImageWriterSpi extends ImageWriterSpi {

    private static final String vendorName = "Oracle Corporation";

    private static final String version = "1.0";

    private static final String[] names = { "gif", "GIF" };

    private static final String[] suffixes = { "gif" };

    private static final String[] MIMETypes = { "image/gif" };

    private static final String writerClassName =
    "com.sun.imageio.plugins.gif.GIFImageWriter";

    private static final String[] readerSpiNames = {
        "com.sun.imageio.plugins.gif.GIFImageReaderSpi"
    };

    public GIFImageWriterSpi() {
        super(vendorName,
              version,
              names,
              suffixes,
              MIMETypes,
              writerClassName,
              new Class[] { ImageOutputStream.class },
              readerSpiNames,
              true,
              GIFWritableStreamMetadata.NATIVE_FORMAT_NAME,
              "com.sun.imageio.plugins.gif.GIFStreamMetadataFormat",
              null, null,
              true,
              GIFWritableImageMetadata.NATIVE_FORMAT_NAME,
              "com.sun.imageio.plugins.gif.GIFImageMetadataFormat",
              null, null
              );
    }

    public boolean canEncodeImage(ImageTypeSpecifier type) {
        if (type == null) {
            throw new IllegalArgumentException("type == null!");
        }

        SampleModel sm = type.getSampleModel();
        ColorModel cm = type.getColorModel();

        boolean canEncode = sm.getNumBands() == 1 &&
            sm.getSampleSize(0) <= 8 &&
            sm.getWidth() <= 65535 &&
            sm.getHeight() <= 65535 &&
            (cm == null || cm.getComponentSize()[0] <= 8);

        if (canEncode) {
            return true;
        } else {
            return PaletteBuilder.canCreatePalette(type);
        }
    }

    public String getDescription(Locale locale) {
        return "Standard GIF image writer";
    }

    public ImageWriter createWriterInstance(Object extension) {
        return new GIFImageWriter(this);
    }
}

⏎ com/sun/imageio/plugins/gif/GIFImageWriterSpi.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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