JDK 1.1 source code directory contains Java source code for JDK 1.1 core classes: "C:\fyicenter\jdk-1.1.8\src".

Here is the list of Java classes of the JDK 1.1 source code:

⏎ java/util/Observer.java

/*
 * @(#)Observer.java	1.12 01/12/10
 *
 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package java.util;

/**
 * A class can implement the <code>Observer</code> interface when it 
 * wants to be informed of changes in observable objects. 
 *
 * @author  Chris Warth
 * @version 1.12, 12/10/01
 * @see     java.util.Observable
 * @since   JDK1.0
 */
public interface Observer { 
    /**
     * This method is called whenever the observed object is changed. An 
     * application calls an observable object's 
     * <code>notifyObservers</code> method  to have all the object's 
     * observers notified of the change. 
     *
     * @param   o     the observable object.
     * @param   arg   an argument passed to the <code>notifyObservers</code>
     *                 method.
     * @since   JDK1.0
     */
    void update(Observable o, Object arg);
}

⏎ java/util/Observer.java

Or download all of them as a single archive file:

File name: jdk-1.1.8-src.zip
File size: 1574187 bytes
Release date: 2018-11-16
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