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/charset/CodingErrorAction.java

/*
 * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.nio.charset;


/**
 * A typesafe enumeration for coding-error actions.
 *
 * <p> Instances of this class are used to specify how malformed-input and
 * unmappable-character errors are to be handled by charset <a
 * href="CharsetDecoder.html#cae">decoders</a> and <a
 * href="CharsetEncoder.html#cae">encoders</a>.  </p>
 *
 *
 * @author Mark Reinhold
 * @author JSR-51 Expert Group
 * @since 1.4
 */

public class CodingErrorAction {

    private String name;

    private CodingErrorAction(String name) {
        this.name = name;
    }

    /**
     * Action indicating that a coding error is to be handled by dropping the
     * erroneous input and resuming the coding operation.
     */
    public static final CodingErrorAction IGNORE
        = new CodingErrorAction("IGNORE");

    /**
     * Action indicating that a coding error is to be handled by dropping the
     * erroneous input, appending the coder's replacement value to the output
     * buffer, and resuming the coding operation.
     */
    public static final CodingErrorAction REPLACE
        = new CodingErrorAction("REPLACE");

    /**
     * Action indicating that a coding error is to be reported, either by
     * returning a {@link CoderResult} object or by throwing a {@link
     * CharacterCodingException}, whichever is appropriate for the method
     * implementing the coding process.
     */
    public static final CodingErrorAction REPORT
        = new CodingErrorAction("REPORT");

    /**
     * Returns a string describing this action.
     *
     * @return  A descriptive string
     */
    public String toString() {
        return name;
    }

}

⏎ java/nio/charset/CodingErrorAction.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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