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/lang/model/type/DeclaredType.java

/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.lang.model.type;


import java.util.List;

import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import javax.lang.model.util.Types;


/**
 * Represents a declared type, either a class type or an interface type.
 * This includes parameterized types such as {@code java.util.Set<String>}
 * as well as raw types.
 *
 * <p> While a {@code TypeElement} represents a class or interface
 * <i>element</i>, a {@code DeclaredType} represents a class
 * or interface <i>type</i>, the latter being a use
 * (or <i>invocation</i>) of the former.
 * See {@link TypeElement} for more on this distinction.
 *
 * <p> The supertypes (both class and interface types) of a declared
 * type may be found using the {@link
 * Types#directSupertypes(TypeMirror)} method.  This returns the
 * supertypes with any type arguments substituted in.
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @see TypeElement
 * @since 1.6
 */
public interface DeclaredType extends ReferenceType {

    /**
     * Returns the element corresponding to this type.
     *
     * @return the element corresponding to this type
     */
    Element asElement();

    /**
     * Returns the type of the innermost enclosing instance or a
     * {@code NoType} of kind {@code NONE} if there is no enclosing
     * instance.  Only types corresponding to inner classes have an
     * enclosing instance.
     *
     * @return a type mirror for the enclosing type
     * @jls 8.1.3 Inner Classes and Enclosing Instances
     * @jls 15.9.2 Determining Enclosing Instances
     */
    TypeMirror getEnclosingType();

    /**
     * Returns the actual type arguments of this type.
     * For a type nested within a parameterized type
     * (such as {@code Outer<String>.Inner<Number>}), only the type
     * arguments of the innermost type are included.
     *
     * @return the actual type arguments of this type, or an empty list
     *           if none
     */
    List<? extends TypeMirror> getTypeArguments();
}

⏎ javax/lang/model/type/DeclaredType.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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