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

⏎ java/nio/ByteBufferAsDoubleBufferRL.java

/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

// -- This file was mechanically generated: Do not edit! -- //

package java.nio;


class ByteBufferAsDoubleBufferRL                  // package-private
    extends ByteBufferAsDoubleBufferL
{








    ByteBufferAsDoubleBufferRL(ByteBuffer bb) {   // package-private












        super(bb);

    }

    ByteBufferAsDoubleBufferRL(ByteBuffer bb,
                                     int mark, int pos, int lim, int cap,
                                     int off)
    {





        super(bb, mark, pos, lim, cap, off);

    }

    public DoubleBuffer slice() {
        int pos = this.position();
        int lim = this.limit();
        assert (pos <= lim);
        int rem = (pos <= lim ? lim - pos : 0);
        int off = (pos << 3) + offset;
        assert (off >= 0);
        return new ByteBufferAsDoubleBufferRL(bb, -1, 0, rem, rem, off);
    }

    public DoubleBuffer duplicate() {
        return new ByteBufferAsDoubleBufferRL(bb,
                                                    this.markValue(),
                                                    this.position(),
                                                    this.limit(),
                                                    this.capacity(),
                                                    offset);
    }

    public DoubleBuffer asReadOnlyBuffer() {








        return duplicate();

    }























    public DoubleBuffer put(double x) {




        throw new ReadOnlyBufferException();

    }

    public DoubleBuffer put(int i, double x) {




        throw new ReadOnlyBufferException();

    }

    public DoubleBuffer compact() {

















        throw new ReadOnlyBufferException();

    }

    public boolean isDirect() {
        return bb.isDirect();
    }

    public boolean isReadOnly() {
        return true;
    }











































    public ByteOrder order() {




        return ByteOrder.LITTLE_ENDIAN;

    }

}

⏎ java/nio/ByteBufferAsDoubleBufferRL.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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