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

⏎ javax/annotation/processing/Completions.java

/*
 * Copyright (c) 2006, 2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.annotation.processing;

/**
 * Utility class for assembling {@link Completion} objects.
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ahé
 * @since 1.6
 */
public class Completions {
    // No instances for you.
    private Completions() {}

    private static class SimpleCompletion implements Completion {
        private String value;
        private String message;

        SimpleCompletion(String value, String message) {
            if (value == null || message == null)
                throw new NullPointerException("Null completion strings not accepted.");
            this.value = value;
            this.message = message;
        }

        public String getValue() {
            return value;
        }


        public String getMessage() {
            return message;
        }

        @Override
        public String toString() {
            return "[\"" + value + "\", \"" + message + "\"]";
        }
        // Default equals and hashCode are fine.
    }

    /**
     * Returns a completion of the value and message.
     *
     * @param value the text of the completion
     * @param message a message about the completion
     * @return a completion of the provided value and message
     */
    public static Completion of(String value, String message) {
        return new SimpleCompletion(value, message);
    }

    /**
     * Returns a completion of the value and an empty message
     *
     * @param value the text of the completion
     * @return a completion of the value and an empty message
     */
    public static Completion of(String value) {
        return new SimpleCompletion(value, "");
    }
}

⏎ javax/annotation/processing/Completions.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

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

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

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