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/awt/peer/TextComponentPeer.java

/*
 * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt.peer;

import java.awt.TextComponent;
import java.awt.im.InputMethodRequests;

/**
 * The peer interface for {@link TextComponent}.
 *
 * The peer interfaces are intended only for use in porting
 * the AWT. They are not intended for use by application
 * developers, and developers should not implement peers
 * nor invoke any of the peer methods directly on the peer
 * instances.
 */
public interface TextComponentPeer extends ComponentPeer {

    /**
     * Sets if the text component should be editable or not.
     *
     * @param editable {@code true} for editable text components,
     *        {@code false} for non-editable text components
     *
     * @see TextComponent#setEditable(boolean)
     */
    void setEditable(boolean editable);

    /**
     * Returns the current content of the text component.
     *
     * @return the current content of the text component
     *
     * @see TextComponent#getText()
     */
    String getText();

    /**
     * Sets the content for the text component.
     *
     * @param text the content to set
     *
     * @see TextComponent#setText(String)
     */
    void setText(String text);

    /**
     * Returns the start index of the current selection.
     *
     * @return the start index of the current selection
     *
     * @see TextComponent#getSelectionStart()
     */
    int getSelectionStart();

    /**
     * Returns the end index of the current selection.
     *
     * @return the end index of the current selection
     *
     * @see TextComponent#getSelectionEnd()
     */
    int getSelectionEnd();

    /**
     * Selects an area of the text component.
     *
     * @param selStart the start index of the new selection
     * @param selEnd the end index of the new selection
     *
     * @see TextComponent#select(int, int)
     */
    void select(int selStart, int selEnd);

    /**
     * Sets the caret position of the text component.
     *
     * @param pos the caret position to set
     *
     * @see TextComponent#setCaretPosition(int)
     */
    void setCaretPosition(int pos);

    /**
     * Returns the current caret position.
     *
     * @return the current caret position
     *
     * @see TextComponent#getCaretPosition()
     */
    int getCaretPosition();

    /**
     * Returns the input method requests.
     *
     * @return the input method requests
     */
    InputMethodRequests getInputMethodRequests();
}

⏎ java/awt/peer/TextComponentPeer.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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