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/awt/GraphicsConfigTemplate.java

/*
 * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 *
 *
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 *
 */

package java.awt;

import java.io.*;

/**
 * The <code>GraphicsConfigTemplate</code> class is used to obtain a valid
 * {@link GraphicsConfiguration}.  A user instantiates one of these
 * objects and then sets all non-default attributes as desired.  The
 * {@link GraphicsDevice#getBestConfiguration} method found in the
 * {@link GraphicsDevice} class is then called with this
 * <code>GraphicsConfigTemplate</code>.  A valid
 * <code>GraphicsConfiguration</code> is returned that meets or exceeds
 * what was requested in the <code>GraphicsConfigTemplate</code>.
 * @see GraphicsDevice
 * @see GraphicsConfiguration
 *
 * @since       1.2
 */
public abstract class GraphicsConfigTemplate implements Serializable {
    /*
     * serialVersionUID
     */
    private static final long serialVersionUID = -8061369279557787079L;

    /**
     * This class is an abstract class so only subclasses can be
     * instantiated.
     */
    public GraphicsConfigTemplate() {
    }

    /**
     * Value used for "Enum" (Integer) type.  States that this
     * feature is required for the <code>GraphicsConfiguration</code>
     * object.  If this feature is not available, do not select the
     * <code>GraphicsConfiguration</code> object.
     */
    public static final int REQUIRED    = 1;

    /**
     * Value used for "Enum" (Integer) type.  States that this
     * feature is desired for the <code>GraphicsConfiguration</code>
     * object.  A selection with this feature is preferred over a
     * selection that does not include this feature, although both
     * selections can be considered valid matches.
     */
    public static final int PREFERRED   = 2;

    /**
     * Value used for "Enum" (Integer) type.  States that this
     * feature is not necessary for the selection of the
     * <code>GraphicsConfiguration</code> object.  A selection
     * without this feature is preferred over a selection that
     * includes this feature since it is not used.
     */
    public static final int UNNECESSARY = 3;

    /**
     * Returns the "best" configuration possible that passes the
     * criteria defined in the <code>GraphicsConfigTemplate</code>.
     * @param gc the array of <code>GraphicsConfiguration</code>
     * objects to choose from.
     * @return a <code>GraphicsConfiguration</code> object that is
     * the best configuration possible.
     * @see GraphicsConfiguration
     */
    public abstract GraphicsConfiguration
      getBestConfiguration(GraphicsConfiguration[] gc);

    /**
     * Returns a <code>boolean</code> indicating whether or
     * not the specified <code>GraphicsConfiguration</code> can be
     * used to create a drawing surface that supports the indicated
     * features.
     * @param gc the <code>GraphicsConfiguration</code> object to test
     * @return <code>true</code> if this
     * <code>GraphicsConfiguration</code> object can be used to create
     * surfaces that support the indicated features;
     * <code>false</code> if the <code>GraphicsConfiguration</code> can
     * not be used to create a drawing surface usable by this Java(tm)
     * API.
     */
    public abstract boolean
      isGraphicsConfigSupported(GraphicsConfiguration gc);

}

⏎ java/awt/GraphicsConfigTemplate.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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