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/naming/ldap/BasicControl.java

/*
 * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.naming.ldap;

/**
 * This class provides a basic implementation of the <tt>Control</tt>
 * interface. It represents an LDAPv3 Control as defined in
 * <a href="http://www.ietf.org/rfc/rfc2251.txt">RFC 2251</a>.
 *
 * @since 1.5
 * @author Vincent Ryan
 */
public class BasicControl implements Control {

    /**
     * The control's object identifier string.
     *
     * @serial
     */
    protected String id;

    /**
     * The control's criticality.
     *
     * @serial
     */
    protected boolean criticality = false; // default

    /**
     * The control's ASN.1 BER encoded value.
     *
     * @serial
     */
    protected byte[] value = null;

    private static final long serialVersionUID = -4233907508771791687L;

    /**
     * Constructs a non-critical control.
     *
     * @param   id      The control's object identifier string.
     *
     */
    public BasicControl(String id) {
        this.id = id;
    }

    /**
     * Constructs a control using the supplied arguments.
     *
     * @param   id              The control's object identifier string.
     * @param   criticality     The control's criticality.
     * @param   value           The control's ASN.1 BER encoded value.
     *                          It is not cloned - any changes to value
     *                          will affect the contents of the control.
     *                          It may be null.
     */
    public BasicControl(String id, boolean criticality, byte[] value) {
        this.id = id;
        this.criticality = criticality;
        this.value = value;
    }

    /**
     * Retrieves the control's object identifier string.
     *
     * @return The non-null object identifier string.
     */
    public String getID() {
        return id;
    }

    /**
     * Determines the control's criticality.
     *
     * @return true if the control is critical; false otherwise.
     */
    public boolean isCritical() {
        return criticality;
    }

    /**
     * Retrieves the control's ASN.1 BER encoded value.
     * The result includes the BER tag and length for the control's value but
     * does not include the control's object identifier and criticality setting.
     *
     * @return A possibly null byte array representing the control's
     *          ASN.1 BER encoded value. It is not cloned - any changes to the
     *          returned value will affect the contents of the control.
     */
    public byte[] getEncodedValue() {
        return value;
    }
}

⏎ javax/naming/ldap/BasicControl.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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