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/net/SocksConsts.java

/*
 * Copyright (c) 2000, 2001, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */
package java.net;

/**
 * Constants used by the SOCKS protocol implementation.
 */

interface SocksConsts {
    static final int PROTO_VERS4                = 4;
    static final int PROTO_VERS         = 5;
    static final int DEFAULT_PORT               = 1080;

    static final int NO_AUTH            = 0;
    static final int GSSAPI             = 1;
    static final int USER_PASSW         = 2;
    static final int NO_METHODS         = -1;

    static final int CONNECT            = 1;
    static final int BIND                       = 2;
    static final int UDP_ASSOC          = 3;

    static final int IPV4                       = 1;
    static final int DOMAIN_NAME                = 3;
    static final int IPV6                       = 4;

    static final int REQUEST_OK         = 0;
    static final int GENERAL_FAILURE    = 1;
    static final int NOT_ALLOWED                = 2;
    static final int NET_UNREACHABLE    = 3;
    static final int HOST_UNREACHABLE   = 4;
    static final int CONN_REFUSED               = 5;
    static final int TTL_EXPIRED                = 6;
    static final int CMD_NOT_SUPPORTED  = 7;
    static final int ADDR_TYPE_NOT_SUP  = 8;
}

⏎ java/net/SocksConsts.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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