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/io/UTFDataFormatException.java

/*
 * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.io;

/**
 * Signals that a malformed string in
 * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
 * format has been read in a data
 * input stream or by any class that implements the data input
 * interface.
 * See the
 * <a href="DataInput.html#modified-utf-8"><code>DataInput</code></a>
 * class description for the format in
 * which modified UTF-8 strings are read and written.
 *
 * @author  Frank Yellin
 * @see     java.io.DataInput
 * @see     java.io.DataInputStream#readUTF(java.io.DataInput)
 * @see     java.io.IOException
 * @since   JDK1.0
 */
public
class UTFDataFormatException extends IOException {
    private static final long serialVersionUID = 420743449228280612L;

    /**
     * Constructs a <code>UTFDataFormatException</code> with
     * <code>null</code> as its error detail message.
     */
    public UTFDataFormatException() {
        super();
    }

    /**
     * Constructs a <code>UTFDataFormatException</code> with the
     * specified detail message. The string <code>s</code> can be
     * retrieved later by the
     * <code>{@link java.lang.Throwable#getMessage}</code>
     * method of class <code>java.lang.Throwable</code>.
     *
     * @param   s   the detail message.
     */
    public UTFDataFormatException(String s) {
        super(s);
    }
}

⏎ java/io/UTFDataFormatException.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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