/*
 
* 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
 
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*/

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</b> 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
   
objthe 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();
    
}
}