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

⏎ org/omg/IOP/CodecOperations.java

package org.omg.IOP;


/**
* org/omg/IOP/CodecOperations.java .
* Generated by the IDL-to-Java compiler (portable), version "3.2"
* from c:/re/workspace/8-2-build-windows-amd64-cygwin/jdk8u191/11896/corba/src/share/classes/org/omg/PortableInterceptor/IOP.idl
* Saturday, October 6, 2018 9:30:42 AM PDT
*/


/**
   * The formats of IOR components and service context data used by ORB 
   * services are often defined as CDR encapsulations encoding instances 
   * of IDL defined data types. The <code>Codec</code> provides a mechanism 
   * to transfer these components between their IDL data types and their CDR 
   * encapsulation representations. 
   * <p>
   * A <code>Codec</code> is obtained from the <code>CodecFactory</code>. 
   * The <code>CodecFactory</code> is obtained through a call to 
   * <code>ORB.resolve_initial_references( "CodecFactory" )</code>.
   */
public interface CodecOperations 
{

  /**
     * Converts the given any into a byte array based on the encoding 
     * format effective for this <code>Codec</code>. 
     *
     * @param data The data, in the form of an any, to be encoded into 
     *     a byte array.
     * @return A byte array containing the encoded Any. This byte array 
     *     contains both the <code>TypeCode</code> and the data of the type.
     * @exception InvalidTypeForEncoding thrown if the type is not valid for 
     *     the encoding format effective for this <code>Codec</code>.
     */
  byte[] encode (org.omg.CORBA.Any data) throws org.omg.IOP.CodecPackage.InvalidTypeForEncoding;

  /**
     * Decodes the given byte array into an Any based on the encoding 
     * format effective for this <code>Codec</code>. 
     * 
     * @param data The data, in the form of a byte array, to be decoded into 
     *     an Any. 
     * @return An Any containing the data from the decoded byte array.
     * @exception FormatMismatch is thrown if the byte array cannot be 
     *     decoded into an Any. 
     */
  org.omg.CORBA.Any decode (byte[] data) throws org.omg.IOP.CodecPackage.FormatMismatch;

  /**
     * Converts the given any into a byte array based on the encoding 
     * format effective for this Codec. Only the data from the Any is 
     * encoded, not the <code>TypeCode</code>. 
     *
     * @param data The data, in the form of an Any, to be encoded into 
     *     a byte array. 
     * @return A byte array containing the data from the encoded any.
     * @exception InvalidTypeForEncoding thrown if the type is not valid for 
     *     the encoding format effective for this <code>Codec</code>.
     */
  byte[] encode_value (org.omg.CORBA.Any data) throws org.omg.IOP.CodecPackage.InvalidTypeForEncoding;

  /**
     * Decodes the given byte array into an Any based on the given 
     * <code>TypeCode</code> and the encoding format effective for 
     * this <code>Codec</code>. 
     *
     * @param data The data, in the form of a byte array, to be decoded 
     *     into an Any. 
     * @param tc The TypeCode to be used to decode the data. 
     * @return An Any containing the data from the decoded byte array.
     * @exception FormatMismatch thrown if the byte array cannot be 
     *     decoded into an Any. 
     */
  org.omg.CORBA.Any decode_value (byte[] data, org.omg.CORBA.TypeCode tc) throws org.omg.IOP.CodecPackage.FormatMismatch, org.omg.IOP.CodecPackage.TypeMismatch;
} // interface CodecOperations

⏎ org/omg/IOP/CodecOperations.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - com.* Package Source Code

⇐ JRE 8 rt.jar - javax.* Package Source Code

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