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

⏎ com/sun/org/apache/bcel/internal/classfile/Deprecated.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.org.apache.bcel.internal.classfile;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache BCEL" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache BCEL", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import  com.sun.org.apache.bcel.internal.Constants;
import  java.io.*;

/**
 * This class is derived from <em>Attribute</em> and denotes that this is a
 * deprecated method.
 * It is instantiated from the <em>Attribute.readAttribute()</em> method.
 *
 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
 * @see     Attribute
 */
public final class Deprecated extends Attribute {
  private byte[] bytes;

  /**
   * Initialize from another object. Note that both objects use the same
   * references (shallow copy). Use clone() for a physical copy.
   */
  public Deprecated(Deprecated c) {
    this(c.getNameIndex(), c.getLength(), c.getBytes(), c.getConstantPool());
  }

  /**
   * @param name_index Index in constant pool to CONSTANT_Utf8
   * @param length Content length in bytes
   * @param bytes Attribute contents
   * @param constant_pool Array of constants
   */
  public Deprecated(int name_index, int length, byte[] bytes,
                    ConstantPool constant_pool)
  {
    super(Constants.ATTR_DEPRECATED, name_index, length, constant_pool);
    this.bytes = bytes;
  }

  /**
   * Construct object from file stream.
   * @param name_index Index in constant pool to CONSTANT_Utf8
   * @param length Content length in bytes
   * @param file Input stream
   * @param constant_pool Array of constants
   * @throws IOException
   */
  Deprecated(int name_index, int length, DataInputStream file,
             ConstantPool constant_pool) throws IOException
  {
    this(name_index, length, (byte [])null, constant_pool);

    if(length > 0) {
      bytes = new byte[length];
      file.readFully(bytes);
      System.err.println("Deprecated attribute with length > 0");
    }
  }

  /**
   * Called by objects that are traversing the nodes of the tree implicitely
   * defined by the contents of a Java class. I.e., the hierarchy of methods,
   * fields, attributes, etc. spawns a tree of objects.
   *
   * @param v Visitor object
   */
  public void accept(Visitor v) {
    v.visitDeprecated(this);
  }

  /**
   * Dump source file attribute to file stream in binary format.
   *
   * @param file Output file stream
   * @throws IOException
   */
  public final void dump(DataOutputStream file) throws IOException
  {
    super.dump(file);

    if(length > 0)
      file.write(bytes, 0, length);
  }

  /**
   * @return data bytes.
   */
  public final byte[] getBytes() { return bytes; }

  /**
   * @param bytes.
   */
  public final void setBytes(byte[] bytes) {
    this.bytes = bytes;
  }

  /**
   * @return attribute name
   */
  public final String toString() {
    return Constants.ATTRIBUTE_NAMES[Constants.ATTR_DEPRECATED];
  }

  /**
   * @return deep copy of this attribute
   */
  public Attribute copy(ConstantPool constant_pool) {
    Deprecated c = (Deprecated)clone();

    if(bytes != null)
      c.bytes = (byte[])bytes.clone();

    c.constant_pool = constant_pool;
    return c;
  }
}

⏎ com/sun/org/apache/bcel/internal/classfile/Deprecated.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
Download 

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