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/sql/DriverPropertyInfo.java

/*
 * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package java.sql;

/**
 * <p>Driver properties for making a connection. The
 * <code>DriverPropertyInfo</code> class is of interest only to advanced programmers
 * who need to interact with a Driver via the method
 * <code>getDriverProperties</code> to discover
 * and supply properties for connections.
 */

public class DriverPropertyInfo {

    /**
     * Constructs a <code>DriverPropertyInfo</code> object with a  given
     * name and value.  The <code>description</code> and <code>choices</code>
     * are initialized to <code>null</code> and <code>required</code> is initialized
     * to <code>false</code>.
     *
     * @param name the name of the property
     * @param value the current value, which may be null
     */
    public DriverPropertyInfo(String name, String value) {
        this.name = name;
        this.value = value;
    }

    /**
     * The name of the property.
     */
    public String name;

    /**
     * A brief description of the property, which may be null.
     */
    public String description = null;

    /**
     * The <code>required</code> field is <code>true</code> if a value must be
         * supplied for this property
     * during <code>Driver.connect</code> and <code>false</code> otherwise.
     */
    public boolean required = false;

    /**
     * The <code>value</code> field specifies the current value of
         * the property, based on a combination of the information
         * supplied to the method <code>getPropertyInfo</code>, the
     * Java environment, and the driver-supplied default values.  This field
     * may be null if no value is known.
     */
    public String value = null;

    /**
     * An array of possible values if the value for the field
         * <code>DriverPropertyInfo.value</code> may be selected
         * from a particular set of values; otherwise null.
     */
    public String[] choices = null;
}

⏎ java/sql/DriverPropertyInfo.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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