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/java/swing/plaf/motif/resources/motif.java

package com.sun.java.swing.plaf.motif.resources;

import java.util.ListResourceBundle;

public final class motif extends ListResourceBundle {
    protected final Object[][] getContents() {
        return new Object[][] {
            { "FileChooser.acceptAllFileFilter.textAndMnemonic", "*" },
            { "FileChooser.cancelButton.textAndMnemonic", "Cancel" },
            { "FileChooser.cancelButtonToolTip.textAndMnemonic", "Abort file chooser dialog." },
            { "FileChooser.enterFileNameLabel.textAndMnemonic", "E&nter file name:" },
            { "FileChooser.enterFolderNameLabel.textAndMnemonic", "Enter folder name:" },
            { "FileChooser.filesLabel.textAndMnemonic", "F&iles" },
            { "FileChooser.filterLabel.textAndMnemonic", "Filte&r" },
            { "FileChooser.foldersLabel.textAndMnemonic", "Fo&lders" },
            { "FileChooser.helpButton.textAndMnemonic", "Help" },
            { "FileChooser.helpButtonToolTip.textAndMnemonic", "FileChooser help." },
            { "FileChooser.openButton.textAndMnemonic", "OK" },
            { "FileChooser.openButtonToolTip.textAndMnemonic", "Open selected file." },
            { "FileChooser.openDialogTitle.textAndMnemonic", "Open" },
            { "FileChooser.pathLabel.textAndMnemonic", "Enter &path or folder name:" },
            { "FileChooser.saveButton.textAndMnemonic", "Save" },
            { "FileChooser.saveButtonToolTip.textAndMnemonic", "Save selected file." },
            { "FileChooser.saveDialogTitle.textAndMnemonic", "Save" },
            { "FileChooser.updateButton.textAndMnemonic", "Update" },
            { "FileChooser.updateButtonToolTip.textAndMnemonic", "Update directory listing." },
        };
    }
}

⏎ com/sun/java/swing/plaf/motif/resources/motif.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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