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/CompositeContext.java

/*
 * Copyright (c) 1997, 1998, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt;

import java.awt.image.Raster;
import java.awt.image.WritableRaster;

/**
 * The <code>CompositeContext</code> interface defines the encapsulated
 * and optimized environment for a compositing operation.
 * <code>CompositeContext</code> objects maintain state for
 * compositing operations.  In a multi-threaded environment, several
 * contexts can exist simultaneously for a single {@link Composite}
 * object.
 * @see Composite
 */

public interface CompositeContext {
    /**
     * Releases resources allocated for a context.
     */
    public void dispose();

    /**
     * Composes the two source {@link Raster} objects and
     * places the result in the destination
     * {@link WritableRaster}.  Note that the destination
     * can be the same object as either the first or second
     * source. Note that <code>dstIn</code> and
     * <code>dstOut</code> must be compatible with the
     * <code>dstColorModel</code> passed to the
     * {@link Composite#createContext(java.awt.image.ColorModel, java.awt.image.ColorModel, java.awt.RenderingHints) createContext}
     * method of the <code>Composite</code> interface.
     * @param src the first source for the compositing operation
     * @param dstIn the second source for the compositing operation
     * @param dstOut the <code>WritableRaster</code> into which the
     * result of the operation is stored
     * @see Composite
     */
    public void compose(Raster src,
                        Raster dstIn,
                        WritableRaster dstOut);


}

⏎ java/awt/CompositeContext.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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