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 javax.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ javax/swing/DesktopManager.java

/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.swing;

/** DesktopManager objects are owned by a JDesktopPane object. They are responsible
  * for implementing L&F specific behaviors for the JDesktopPane. JInternalFrame
  * implementations should delegate specific behaviors to the DesktopManager. For
  * instance, if a JInternalFrame was asked to iconify, it should try:
  * <PRE>
  *    getDesktopPane().getDesktopManager().iconifyFrame(frame);
  * </PRE>
  * This delegation allows each L&amp;F to provide custom behaviors for desktop-specific
  * actions. (For example, how and where the internal frame's icon would appear.)
  * <p>This class provides a policy for the various JInternalFrame methods, it is not
  * meant to be called directly rather the various JInternalFrame methods will call
  * into the DesktopManager.</p>
  *
  * @see JDesktopPane
  * @see JInternalFrame
  * @see JInternalFrame.JDesktopIcon
  *
  * @author David Kloba
  */
public interface DesktopManager
{
    /** If possible, display this frame in an appropriate location.
      * Normally, this is not called, as the creator of the JInternalFrame
      * will add the frame to the appropriate parent.
      */
    void openFrame(JInternalFrame f);

    /** Generally, this call should remove the frame from it's parent. */
    void closeFrame(JInternalFrame f);

    /** Generally, the frame should be resized to match it's parents bounds. */
    void maximizeFrame(JInternalFrame f);
    /** Generally, this indicates that the frame should be restored to it's
      * size and position prior to a maximizeFrame() call.
      */
    void minimizeFrame(JInternalFrame f);
    /** Generally, remove this frame from it's parent and add an iconic representation. */
    void iconifyFrame(JInternalFrame f);
    /** Generally, remove any iconic representation that is present and restore the
      * frame to it's original size and location.
      */
    void deiconifyFrame(JInternalFrame f);

    /**
     * Generally, indicate that this frame has focus. This is usually called after
     * the JInternalFrame's IS_SELECTED_PROPERTY has been set to true.
     */
    void activateFrame(JInternalFrame f);

    /**
     * Generally, indicate that this frame has lost focus. This is usually called
     * after the JInternalFrame's IS_SELECTED_PROPERTY has been set to false.
     */
    void deactivateFrame(JInternalFrame f);

    /** This method is normally called when the user has indicated that
      * they will begin dragging a component around. This method should be called
      * prior to any dragFrame() calls to allow the DesktopManager to prepare any
      * necessary state. Normally <b>f</b> will be a JInternalFrame.
      */
    void beginDraggingFrame(JComponent f);

    /** The user has moved the frame. Calls to this method will be preceded by calls
      * to beginDraggingFrame().
      *  Normally <b>f</b> will be a JInternalFrame.
      */
    void dragFrame(JComponent f, int newX, int newY);
    /** This method signals the end of the dragging session. Any state maintained by
      * the DesktopManager can be removed here.  Normally <b>f</b> will be a JInternalFrame.
      */
    void endDraggingFrame(JComponent f);

    /** This methods is normally called when the user has indicated that
      * they will begin resizing the frame. This method should be called
      * prior to any resizeFrame() calls to allow the DesktopManager to prepare any
      * necessary state.  Normally <b>f</b> will be a JInternalFrame.
      */
    void beginResizingFrame(JComponent f, int direction);
    /** The user has resized the component. Calls to this method will be preceded by calls
      * to beginResizingFrame().
      *  Normally <b>f</b> will be a JInternalFrame.
      */
    void resizeFrame(JComponent f, int newX, int newY, int newWidth, int newHeight);
    /** This method signals the end of the resize session. Any state maintained by
      * the DesktopManager can be removed here.  Normally <b>f</b> will be a JInternalFrame.
      */
    void endResizingFrame(JComponent f);

    /** This is a primitive reshape method.*/
    void setBoundsForFrame(JComponent f, int newX, int newY, int newWidth, int newHeight);
}

⏎ javax/swing/DesktopManager.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - org.* Package Source Code

⇐ JRE 8 rt.jar - java.* Package Source Code

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