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/io/ObjectOutput.java

/*
 * @(#)ObjectOutput.java	1.8 01/12/10
 *
 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.io;

/**
 * ObjectOutput extends the DataOutput interface to include writing of objects.
 * DataOutput includes methods for output of primitive types, ObjectOutput
 * extends that interface to include objects, arrays, and Strings.
 *
 * @author  unascribed
 * @version 1.8, 12/10/01
 * @see java.io.InputStream
 * @see java.io.ObjectOutputStream
 * @see java.io.ObjectInputStream
 * @since   JDK1.1
 */
public interface ObjectOutput extends DataOutput {
    /**
     * Write an object to the underlying storage or stream.  The
     * class that implements this interface defines how the object is
     * written.
     *
     * @exception IOException Any of the usual Input/Output related exceptions.
     * @since     JDK1.1
     */
    public void writeObject(Object obj)
      throws IOException;

    /**
     * Writes a byte. This method will block until the byte is actually
     * written.
     * @param b	the byte
     * @exception IOException If an I/O error has occurred.
     * @since     JDK1.1
     */
    public void write(int b) throws IOException;

    /**
     * Writes an array of bytes. This method will block until the bytes
     * are actually written.
     * @param b	the data to be written
     * @exception IOException If an I/O error has occurred.
     * @since     JDK1.1
     */
    public void write(byte b[]) throws IOException;

    /**
     * Writes a sub array of bytes. 
     * @param b	the data to be written
     * @param off	the start offset in the data
     * @param len	the number of bytes that are written
     * @exception IOException If an I/O error has occurred.
     * @since     JDK1.1
     */
    public void write(byte b[], int off, int len) throws IOException;

    /**
     * Flushes the stream. This will write any buffered
     * output bytes.
     * @exception IOException If an I/O error has occurred.
     * @since     JDK1.1
     */
    public void flush() throws IOException;

    /**
     * Closes the stream. This method must be called
     * to release any resources associated with the
     * stream.
     * @exception IOException If an I/O error has occurred.
     * @since     JDK1.1
     */
    public void close() throws IOException;
}

⏎ java/io/ObjectOutput.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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