Java example source code file (Proxy.java)

This example Java source code file (Proxy.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

direct, http, illegalargumentexception, inetsocketaddress, no_proxy, proxy, socketaddress, socks, string, type

The Proxy.java Java example source code

/*
 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package java.net;

/**
 * This class represents a proxy setting, typically a type (http, socks) and
 * a socket address.
 * A {@code Proxy} is an immutable object.
 *
 * @see     java.net.ProxySelector
 * @author Yingxian Wang
 * @author Jean-Christophe Collet
 * @since   1.5
 */
public class Proxy {

    /**
     * Represents the proxy type.
     *
     * @since 1.5
     */
    public enum Type {
        /**
         * Represents a direct connection, or the absence of a proxy.
         */
        DIRECT,
        /**
         * Represents proxy for high level protocols such as HTTP or FTP.
         */
        HTTP,
        /**
         * Represents a SOCKS (V4 or V5) proxy.
         */
        SOCKS
    };

    private Type type;
    private SocketAddress sa;

    /**
     * A proxy setting that represents a {@code DIRECT} connection,
     * basically telling the protocol handler not to use any proxying.
     * Used, for instance, to create sockets bypassing any other global
     * proxy settings (like SOCKS):
     * <P>
     * {@code Socket s = new Socket(Proxy.NO_PROXY);}
     *
     */
    public final static Proxy NO_PROXY = new Proxy();

    // Creates the proxy that represents a {@code DIRECT} connection.
    private Proxy() {
        type = Type.DIRECT;
        sa = null;
    }

    /**
     * Creates an entry representing a PROXY connection.
     * Certain combinations are illegal. For instance, for types Http, and
     * Socks, a SocketAddress <b>must be provided.
     * <P>
     * Use the {@code Proxy.NO_PROXY} constant
     * for representing a direct connection.
     *
     * @param type the {@code Type} of the proxy
     * @param sa the {@code SocketAddress} for that proxy
     * @throws IllegalArgumentException when the type and the address are
     * incompatible
     */
    public Proxy(Type type, SocketAddress sa) {
        if ((type == Type.DIRECT) || !(sa instanceof InetSocketAddress))
            throw new IllegalArgumentException("type " + type + " is not compatible with address " + sa);
        this.type = type;
        this.sa = sa;
    }

    /**
     * Returns the proxy type.
     *
     * @return a Type representing the proxy type
     */
    public Type type() {
        return type;
    }

    /**
     * Returns the socket address of the proxy, or
     * {@code null} if its a direct connection.
     *
     * @return a {@code SocketAddress} representing the socket end
     *         point of the proxy
     */
    public SocketAddress address() {
        return sa;
    }

    /**
     * Constructs a string representation of this Proxy.
     * This String is constructed by calling toString() on its type
     * and concatenating " @ " and the toString() result from its address
     * if its type is not {@code DIRECT}.
     *
     * @return  a string representation of this object.
     */
    public String toString() {
        if (type() == Type.DIRECT)
            return "DIRECT";
        return type() + " @ " + address();
    }

        /**
     * Compares this object against the specified object.
     * The result is {@code true} if and only if the argument is
     * not {@code null} and it represents the same proxy as
     * this object.
     * <p>
     * Two instances of {@code Proxy} represent the same
     * address if both the SocketAddresses and type are equal.
     *
     * @param   obj   the object to compare against.
     * @return  {@code true} if the objects are the same;
     *          {@code false} otherwise.
     * @see java.net.InetSocketAddress#equals(java.lang.Object)
     */
    public final boolean equals(Object obj) {
        if (obj == null || !(obj instanceof Proxy))
            return false;
        Proxy p = (Proxy) obj;
        if (p.type() == type()) {
            if (address() == null) {
                return (p.address() == null);
            } else
                return address().equals(p.address());
        }
        return false;
    }

    /**
     * Returns a hashcode for this Proxy.
     *
     * @return  a hash code value for this Proxy.
     */
    public final int hashCode() {
        if (address() == null)
            return type().hashCode();
        return type().hashCode() + address().hashCode();
    }
}