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/corba/se/impl/ior/ByteBuffer.java

/*
 * Copyright (c) 2001, 2002, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 *
 *
 *
 *
 *
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 *
 *
 *
 *
 *
 *
 *
 */

package com.sun.corba.se.impl.ior ;


public class ByteBuffer {
    /**
     * The array buffer into which the components of the ByteBuffer are
     * stored. The capacity of the ByteBuffer is the length of this array buffer,
     * and is at least large enough to contain all the ByteBuffer's elements.<p>
     *
     * Any array elements following the last element in the ByteBuffer are 0.
     */
    protected byte elementData[];

    /**
     * The number of valid components in this <tt>ByteBuffer</tt> object.
     * Components <tt>elementData[0]</tt> through
     * <tt>elementData[elementCount-1]</tt> are the actual items.
     *
     * @serial
     */
    protected int elementCount;

    /**
     * The amount by which the capacity of the ByteBuffer is automatically
     * incremented when its size becomes greater than its capacity.  If
     * the capacity increment is less than or equal to zero, the capacity
     * of the ByteBuffer is doubled each time it needs to grow.
     *
     * @serial
     */
    protected int capacityIncrement;

    /**
     * Constructs an empty ByteBuffer with the specified initial capacity and
     * capacity increment.
     *
     * @param   initialCapacity     the initial capacity of the ByteBuffer.
     * @param   capacityIncrement   the amount by which the capacity is
     *                              increased when the ByteBuffer overflows.
     * @exception IllegalArgumentException if the specified initial capacity
     *               is negative
     */
    public ByteBuffer(int initialCapacity, int capacityIncrement) {
        super();
        if (initialCapacity < 0)
            throw new IllegalArgumentException("Illegal Capacity: "+
                                               initialCapacity);
        this.elementData = new byte[initialCapacity];
        this.capacityIncrement = capacityIncrement;
    }

    /**
     * Constructs an empty ByteBuffer with the specified initial capacity and
     * with its capacity increment equal to zero.
     *
     * @param   initialCapacity   the initial capacity of the ByteBuffer.
     * @exception IllegalArgumentException if the specified initial capacity
     *               is negative
     */
    public ByteBuffer(int initialCapacity) {
        this(initialCapacity, 0);
    }

    /**
     * Constructs an empty ByteBuffer so that its internal data array
     * has size <tt>10</tt> and its standard capacity increment is
     * zero.
     */
    public ByteBuffer() {
        this(200);
    }

    /**
     * Trims the capacity of this ByteBuffer to be the ByteBuffer's current
     * size. If the capacity of this cector is larger than its current
     * size, then the capacity is changed to equal the size by replacing
     * its internal data array, kept in the field <tt>elementData</tt>,
     * with a smaller one. An application can use this operation to
     * minimize the storage of a ByteBuffer.
     */
    public void trimToSize() {
        int oldCapacity = elementData.length;
        if (elementCount < oldCapacity) {
            byte oldData[] = elementData;
            elementData = new byte[elementCount];
            System.arraycopy(oldData, 0, elementData, 0, elementCount);
        }
    }

    /**
     * This implements the unsynchronized semantics of ensureCapacity.
     * Synchronized methods in this class can internally call this
     * method for ensuring capacity without incurring the cost of an
     * extra synchronization.
     *
     * @see java.util.ByteBuffer#ensureCapacity(int)
     */
    private void ensureCapacityHelper(int minCapacity) {
        int oldCapacity = elementData.length;
        if (minCapacity > oldCapacity) {
            byte oldData[] = elementData;
            int newCapacity = (capacityIncrement > 0) ?
                (oldCapacity + capacityIncrement) : (oldCapacity * 2);
            if (newCapacity < minCapacity) {
                newCapacity = minCapacity;
            }
            elementData = new byte[newCapacity];
            System.arraycopy(oldData, 0, elementData, 0, elementCount);
        }
    }

    /**
     * Returns the current capacity of this ByteBuffer.
     *
     * @return  the current capacity (the length of its internal
     *          data arary, kept in the field <tt>elementData</tt>
     *          of this ByteBuffer.
     */
    public int capacity() {
        return elementData.length;
    }

    /**
     * Returns the number of components in this ByteBuffer.
     *
     * @return  the number of components in this ByteBuffer.
     */
    public int size() {
        return elementCount;
    }

    /**
     * Tests if this ByteBuffer has no components.
     *
     * @return  <code>true</code> if and only if this ByteBuffer has
     *          no components, that is, its size is zero;
     *          <code>false</code> otherwise.
     */
    public boolean isEmpty() {
        return elementCount == 0;
    }

    public void append(byte value)
    {
        ensureCapacityHelper(elementCount + 1);
        elementData[elementCount++] = value;
    }

    public void append( int value )
    {
        ensureCapacityHelper(elementCount + 4);
        doAppend( value ) ;
    }

    private void doAppend( int value )
    {
        int current = value ;
        for (int ctr=0; ctr<4; ctr++) {
            elementData[elementCount+ctr] = (byte)(current & 255) ;
            current = current >> 8 ;
        }
        elementCount += 4 ;
    }

    public void append( String value )
    {
        byte[] data = value.getBytes() ;
        ensureCapacityHelper( elementCount + data.length + 4 ) ;
        doAppend( data.length ) ;
        System.arraycopy( data, 0, elementData, elementCount, data.length ) ;
        elementCount += data.length ;
    }

    /**
     * Returns an array containing all of the elements in this ByteBuffer
     * in the correct order.
     *
     * @since 1.2
     */
    public byte[] toArray() {
        return elementData ;
    }
}

⏎ com/sun/corba/se/impl/ior/ByteBuffer.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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