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/encoding/TypeCodeReader.java

/*
 * Copyright (c) 2002, 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

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

import java.util.HashMap;
import java.util.Map;
import java.util.Iterator;
import java.util.List;
import java.util.Collections;
import java.util.ArrayList;
import java.io.IOException;
import java.io.PrintStream;
import java.io.ByteArrayOutputStream;
import java.math.BigDecimal;
import java.math.BigInteger;

import org.omg.CORBA.TypeCode ;
import org.omg.CORBA.StructMember ;
import org.omg.CORBA.UnionMember ;
import org.omg.CORBA.ValueMember ;
import org.omg.CORBA.TCKind ;
import org.omg.CORBA.Any ;
import org.omg.CORBA.Principal ;
import org.omg.CORBA.BAD_TYPECODE ;
import org.omg.CORBA.BAD_PARAM ;
import org.omg.CORBA.BAD_OPERATION ;
import org.omg.CORBA.INTERNAL ;
import org.omg.CORBA.MARSHAL ;

import org.omg.CORBA.TypeCodePackage.BadKind ;

import org.omg.CORBA_2_3.portable.InputStream;
import org.omg.CORBA_2_3.portable.OutputStream;

import com.sun.corba.se.spi.ior.iiop.GIOPVersion;
import com.sun.corba.se.impl.corba.TypeCodeImpl;
import com.sun.corba.se.spi.orb.ORB;
import com.sun.corba.se.impl.encoding.OSFCodeSetRegistry;
import com.sun.corba.se.impl.encoding.MarshalInputStream;
import com.sun.corba.se.impl.encoding.CodeSetConversion;
import com.sun.corba.se.impl.encoding.CDRInputStream;
import com.sun.corba.se.impl.encoding.CDROutputStream;

public interface TypeCodeReader extends MarshalInputStream {
    public void addTypeCodeAtPosition(TypeCodeImpl tc, int position);
    public TypeCodeImpl getTypeCodeAtPosition(int position);
    public void setEnclosingInputStream(InputStream enclosure);
    public TypeCodeReader getTopLevelStream();
    public int getTopLevelPosition();
    // for debugging
    //public void printBuffer();
    public int getPosition();
    public void printTypeMap();
}

⏎ com/sun/corba/se/impl/encoding/TypeCodeReader.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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