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/lang/NumberFormatException.java

/*
 * @(#)NumberFormatException.java	1.13 01/12/10
 *
 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.lang;

/**
 * Thrown to indicate that the application has attempted to convert 
 * a string to one of the numeric types, but that the string does not 
 * have the appropriate format. 
 *
 * @author  unascribed
 * @version 1.13, 12/10/01
 * @see     java.lang.Integer#toString()
 * @since   JDK1.0
 */
public
class NumberFormatException extends IllegalArgumentException {
    /**
     * Constructs a <code>NumberFormatException</code> with no detail message.
     *
     * @since   JDK1.0
     */
    public NumberFormatException () {
	super();
    }

    /**
     * Constructs a <code>NumberFormatException</code> with the 
     * specified detail message. 
     *
     * @param   s   the detail message.
     * @since   JDK1.0
     */
    public NumberFormatException (String s) {
	super (s);
    }
}

⏎ java/lang/NumberFormatException.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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