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/security/auth/callback/TextInputCallback.java

/*
 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 */

package javax.security.auth.callback;

/**
 * <p> Underlying security services instantiate and pass a
 * {@code TextInputCallback} to the {@code handle}
 * method of a {@code CallbackHandler} to retrieve generic text
 * information.
 *
 * @see javax.security.auth.callback.CallbackHandler
 */
public class TextInputCallback implements Callback, java.io.Serializable {

    private static final long serialVersionUID = -8064222478852811804L;

    /**
     * @serial
     * @since 1.4
     */
    private String prompt;
    /**
     * @serial
     * @since 1.4
     */
    private String defaultText;
    /**
     * @serial
     * @since 1.4
     */
    private String inputText;

    /**
     * Construct a {@code TextInputCallback} with a prompt.
     *
     * <p>
     *
     * @param prompt the prompt used to request the information.
     *
     * @exception IllegalArgumentException if {@code prompt} is null
     *                  or if {@code prompt} has a length of 0.
     */
    public TextInputCallback(String prompt) {
        if (prompt == null || prompt.length() == 0)
            throw new IllegalArgumentException();
        this.prompt = prompt;
    }

    /**
     * Construct a {@code TextInputCallback} with a prompt
     * and default input value.
     *
     * <p>
     *
     * @param prompt the prompt used to request the information. <p>
     *
     * @param defaultText the text to be used as the default text displayed
     *                  with the prompt.
     *
     * @exception IllegalArgumentException if {@code prompt} is null,
     *                  if {@code prompt} has a length of 0,
     *                  if {@code defaultText} is null
     *                  or if {@code defaultText} has a length of 0.
     */
    public TextInputCallback(String prompt, String defaultText) {
        if (prompt == null || prompt.length() == 0 ||
            defaultText == null || defaultText.length() == 0)
            throw new IllegalArgumentException();

        this.prompt = prompt;
        this.defaultText = defaultText;
    }

    /**
     * Get the prompt.
     *
     * <p>
     *
     * @return the prompt.
     */
    public String getPrompt() {
        return prompt;
    }

    /**
     * Get the default text.
     *
     * <p>
     *
     * @return the default text, or null if this {@code TextInputCallback}
     *          was not instantiated with {@code defaultText}.
     */
    public String getDefaultText() {
        return defaultText;
    }

    /**
     * Set the retrieved text.
     *
     * <p>
     *
     * @param text the retrieved text, which may be null.
     *
     * @see #getText
     */
    public void setText(String text) {
        this.inputText = text;
    }

    /**
     * Get the retrieved text.
     *
     * <p>
     *
     * @return the retrieved text, which may be null.
     *
     * @see #setText
     */
    public String getText() {
        return inputText;
    }
}

⏎ javax/security/auth/callback/TextInputCallback.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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