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/jpeg/JPEGImageMetadataFormatResources.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.jpeg;

import java.util.ListResourceBundle;

public class JPEGImageMetadataFormatResources
       extends JPEGMetadataFormatResources {

    static final Object[][] imageContents = {
        // Node name, followed by description
        { "JPEGvariety", "A node grouping all marker segments specific to the variety of stream being read/written (e.g. JFIF) - may be empty" },
        { "markerSequence", "A node grouping all non-jfif marker segments" },
        { "app0jfif", "A JFIF APP0 marker segment" },
        { "app14Adobe", "An Adobe APP14 marker segment" },
        { "sof", "A Start Of Frame marker segment" },
        { "sos", "A Start Of Scan marker segment" },
        { "app0JFXX", "A JFIF extension marker segment" },
        { "app2ICC", "An ICC profile APP2 marker segment" },
        { "JFIFthumbJPEG",
          "A JFIF thumbnail in JPEG format (no JFIF segments permitted)" },
        { "JFIFthumbPalette", "A JFIF thumbnail as an RGB indexed image" },
        { "JFIFthumbRGB", "A JFIF thumbnail as an RGB image" },
        { "componentSpec", "A component specification for a frame" },
        { "scanComponentSpec", "A component specification for a scan" },

        // Node name + "/" + AttributeName, followed by description
        { "app0JFIF/majorVersion",
          "The major JFIF version number" },
        { "app0JFIF/minorVersion",
          "The minor JFIF version number" },
        { "app0JFIF/resUnits",
          "The resolution units for Xdensity and Ydensity "
          + "(0 = no units, just aspect ratio; 1 = dots/inch; 2 = dots/cm)" },
        { "app0JFIF/Xdensity",
          "The horizontal density or aspect ratio numerator" },
        { "app0JFIF/Ydensity",
          "The vertical density or aspect ratio denominator" },
        { "app0JFIF/thumbWidth",
          "The width of the thumbnail, or 0 if there isn't one" },
        { "app0JFIF/thumbHeight",
          "The height of the thumbnail, or 0 if there isn't one" },
        { "app0JFXX/extensionCode",
          "The JFXX extension code identifying thumbnail type: "
          + "(16 = JPEG, 17 = indexed, 19 = RGB" },
        { "JFIFthumbPalette/thumbWidth",
          "The width of the thumbnail" },
        { "JFIFthumbPalette/thumbHeight",
          "The height of the thumbnail" },
        { "JFIFthumbRGB/thumbWidth",
          "The width of the thumbnail" },
        { "JFIFthumbRGB/thumbHeight",
          "The height of the thumbnail" },
        { "app14Adobe/version",
          "The version of Adobe APP14 marker segment" },
        { "app14Adobe/flags0",
          "The flags0 variable of an APP14 marker segment" },
        { "app14Adobe/flags1",
          "The flags1 variable of an APP14 marker segment" },
        { "app14Adobe/transform",
          "The color transform applied to the image "
          + "(0 = Unknown, 1 = YCbCr, 2 = YCCK)" },
        { "sof/process",
          "The JPEG process (0 = Baseline sequential, "
          + "1 = Extended sequential, 2 = Progressive)" },
        { "sof/samplePrecision",
          "The number of bits per sample" },
        { "sof/numLines",
          "The number of lines in the image" },
        { "sof/samplesPerLine",
          "The number of samples per line" },
        { "sof/numFrameComponents",
          "The number of components in the image" },
        { "componentSpec/componentId",
          "The id for this component" },
        { "componentSpec/HsamplingFactor",
          "The horizontal sampling factor for this component" },
        { "componentSpec/VsamplingFactor",
          "The vertical sampling factor for this component" },
        { "componentSpec/QtableSelector",
          "The quantization table to use for this component" },
        { "sos/numScanComponents",
          "The number of components in the scan" },
        { "sos/startSpectralSelection",
          "The first spectral band included in this scan" },
        { "sos/endSpectralSelection",
          "The last spectral band included in this scan" },
        { "sos/approxHigh",
          "The highest bit position included in this scan" },
        { "sos/approxLow",
          "The lowest bit position included in this scan" },
        { "scanComponentSpec/componentSelector",
          "The id of this component" },
        { "scanComponentSpec/dcHuffTable",
          "The huffman table to use for encoding DC coefficients" },
        { "scanComponentSpec/acHuffTable",
          "The huffman table to use for encoding AC coefficients" }
    };

    public JPEGImageMetadataFormatResources() {}

    protected Object[][] getContents() {
        // return a copy of the combined commonContents and imageContents;
        // in theory we want a deep clone of the combined arrays,
        // but since it only contains (immutable) Strings, this shallow
        // copy is sufficient
        Object[][] combinedContents =
            new Object[commonContents.length + imageContents.length][2];
        int combined = 0;
        for (int i = 0; i < commonContents.length; i++, combined++) {
            combinedContents[combined][0] = commonContents[i][0];
            combinedContents[combined][1] = commonContents[i][1];
        }
        for (int i = 0; i < imageContents.length; i++, combined++) {
            combinedContents[combined][0] = imageContents[i][0];
            combinedContents[combined][1] = imageContents[i][1];
        }
        return combinedContents;
    }
}

⏎ com/sun/imageio/plugins/jpeg/JPEGImageMetadataFormatResources.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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