/*
 
* Copyright (c) 2000, 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;

import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamException;
import java.io.ObjectStreamField;

/**
 
*
 
* This class implements an IP Socket Address (IP address + port number)
 
* It can also be a pair (hostname + port number), in which case an attempt
 
* will be made to resolve the hostname. If resolution fails then the address
 
* is said to be <I>unresolved</I> but can still be used on some circumstances
 
* like connecting through a proxy.
 
* <p>
 
* It provides an immutable object used by sockets for binding, connecting, or
 
* as returned values.
 
* <p>
 
* The <i>wildcard</i> is a special local IP address. It usually means "any"
 
* and can only be used for {@code bind} operations.
 
*
 
*
 
*
 
* @since 1.4
 
*/

public class InetSocketAddress
    
extends SocketAddress
{
    
// Private implementation class pointed to by all public methods.
    
private static class InetSocketAddressHolder {
        
// The hostname of the Socket Address
        
private String hostname;
        
// The IP address of the Socket Address
        
private InetAddress addr;
        
// The port number of the Socket Address
        
private int port;

        
private InetSocketAddressHolder(String hostname, InetAddress addr, int port) {
            
this.hostname = hostname;
            
this.addr = addr;
            
this.port = port;
        
}

        
private int getPort() {
            
return port;
        
}

        
private InetAddress getAddress() {
            
return addr;
        
}

        
private String getHostName() {
            
if (hostname != null)
                
return hostname;
            
if (addr != null)
                
return addr.getHostName();
            
return null;
        
}

        
private String getHostString() {
            
if (hostname != null)
                
return hostname;
            
if (addr != null) {
                
if (addr.holder().getHostName() != null)
                    
return addr.holder().getHostName();
                
else
                    
return
addr.getHostAddress();
            
}
            
return null;
        
}

        
private boolean isUnresolved() {
            
return addr == null;
        
}

        
@Override
        
public String toString() {
            
if (isUnresolved()) {
                
return hostname + ":" + port;
            
} else {
                
return addr.toString() + ":" + port;
            
}
        
}

        
@Override
        
public final boolean equals(Object obj) {
            
if (obj == null || !(obj instanceof InetSocketAddressHolder))
                
return false;
            
InetSocketAddressHolder that = (InetSocketAddressHolder)obj;
            
boolean sameIP;
            
if (addr != null)
                
sameIP = addr.equals(that.addr);
            
else if (hostname != null)
                
sameIP = (that.addr == null) &&
                    
hostname.equalsIgnoreCase(that.hostname);
            
else
                
sameIP = (that.addr == null) && (that.hostname == null);
            
return sameIP && (port == that.port);
        
}

        
@Override
        
public final int hashCode() {
            
if (addr != null)
                
return addr.hashCode() + port;
            
if (hostname != null)
                
return hostname.toLowerCase().hashCode() + port;
            
return port;
        
}
    
}

    
private final transient InetSocketAddressHolder holder;

    
private static final long serialVersionUID = 5076001401234631237L;

    
private static int checkPort(int port) {
        
if (port < 0 || port > 0xFFFF)
            
throw new IllegalArgumentException("port out of range:" + port);
        
return port;
    
}

    
private static String checkHost(String hostname) {
        
if (hostname == null)
            
throw new IllegalArgumentException("hostname can't be null");
        
return hostname;
    
}

    
/**
     
* Creates a socket address where the IP address is the wildcard address
     
* and the port number a specified value.
     
* <p>
     
* A valid port value is between 0 and 65535.
     
* A port number of {@code zero} will let the system pick up an
     
* ephemeral port in a {@code bind} operation.
     
* <p>
     
* @param
   
port
    
The port number
     
* @throws IllegalArgumentException if the port parameter is outside the specified
     
* range of valid port values.
     
*/

    
public InetSocketAddress(int port) {
        
this(InetAddress.anyLocalAddress(), port);
    
}

    
/**
     
*
     
* Creates a socket address from an IP address and a port number.
     
* <p>
     
* A valid port value is between 0 and 65535.
     
* A port number of {@code zero} will let the system pick up an
     
* ephemeral port in a {@code bind} operation.
     
* <P>
     
* A {@code null} address will assign the <i>wildcard</i> address.
     
* <p>
     
* @param
   
addr
    
The IP address
     
* @param
   
port
    
The port number
     
* @throws IllegalArgumentException if the port parameter is outside the specified
     
* range of valid port values.
     
*/

    
public InetSocketAddress(InetAddress addr, int port) {
        
holder = new InetSocketAddressHolder(
                        
null,
                        
addr == null ? InetAddress.anyLocalAddress() : addr,
                        
checkPort(port));
    
}

    
/**
     
*
     
* Creates a socket address from a hostname and a port number.
     
* <p>
     
* An attempt will be made to resolve the hostname into an InetAddress.
     
* If that attempt fails, the address will be flagged as <I>unresolved</I>.
     
* <p>
     
* If there is a security manager, its {@code checkConnect} method
     
* is called with the host name as its argument to check the permission
     
* to resolve it. This could result in a SecurityException.
     
* <P>
     
* A valid port value is between 0 and 65535.
     
* A port number of {@code zero} will let the system pick up an
     
* ephemeral port in a {@code bind} operation.
     
* <P>
     
* @param
   
hostname the Host name
     
* @param
   
port
    
The port number
     
* @throws IllegalArgumentException if the port parameter is outside the range
     
* of valid port values, or if the hostname parameter is <TT>null</TT>.
     
* @throws SecurityException if a security manager is present and
     
*
                           
permission to resolve the host name is
     
*
                           
denied.
     
* @see#isUnresolved()
     
*/

    
public InetSocketAddress(String hostname, int port) {
        
checkHost(hostname);
        
InetAddress addr = null;
        
String host = null;
        
try {
            
addr = InetAddress.getByName(hostname);
        
} catch(UnknownHostException e) {
            
host = hostname;
        
}
        
holder = new InetSocketAddressHolder(host, addr, checkPort(port));
    
}

    
// private constructor for creating unresolved instances
    
private InetSocketAddress(int port, String hostname) {
        
holder = new InetSocketAddressHolder(hostname, null, port);
    
}

    
/**
     
*
     
* Creates an unresolved socket address from a hostname and a port number.
     
* <p>
     
* No attempt will be made to resolve the hostname into an InetAddress.
     
* The address will be flagged as <I>unresolved</I>.
     
* <p>
     
* A valid port value is between 0 and 65535.
     
* A port number of {@code zero} will let the system pick up an
     
* ephemeral port in a {@code bind} operation.
     
* <P>
     
* @param
   
host
    
the Host name
     
* @param
   
port
    
The port number
     
* @throws IllegalArgumentException if the port parameter is outside
     
*
                  
the range of valid port values, or if the hostname
     
*
                  
parameter is <TT>null</TT>.
     
* @see#isUnresolved()
     
* @return
  
a {@code InetSocketAddress} representing the unresolved
     
*
          
socket address
     
* @since 1.5
     
*/

    
public static InetSocketAddress createUnresolved(String host, int port) {
        
return new InetSocketAddress(checkPort(port), checkHost(host));
    
}

    
/**
     
* @serialField hostname String
     
* @serialField addr InetAddress
     
* @serialField port int
     
*/

    
private static final ObjectStreamField[] serialPersistentFields = {
         
new ObjectStreamField("hostname", String.class),
         
new ObjectStreamField("addr", InetAddress.class),
         
new ObjectStreamField("port", int.class)};

    
private void writeObject(ObjectOutputStream out)
        
throws IOException
    
{
        
// Don't call defaultWriteObject()
         
ObjectOutputStream.PutField pfields = out.putFields();
         
pfields.put("hostname", holder.hostname);
         
pfields.put("addr", holder.addr);
         
pfields.put("port", holder.port);
         
out.writeFields();
     
}

    
private void readObject(ObjectInputStream in)
        
throws IOException, ClassNotFoundException
    
{
        
// Don't call defaultReadObject()
        
ObjectInputStream.GetField oisFields = in.readFields();
        
final String oisHostname = (String)oisFields.get("hostname", null);
        
final InetAddress oisAddr = (InetAddress)oisFields.get("addr", null);
        
final int oisPort = oisFields.get("port", -1);

        
// Check that our invariants are satisfied
        
checkPort(oisPort);
        
if (oisHostname == null && oisAddr == null)
            
throw new InvalidObjectException("hostname and addr " +
                                             
"can't both be null");

        
InetSocketAddressHolder h = new InetSocketAddressHolder(oisHostname,
                                                                
oisAddr,
                                                                
oisPort);
        
UNSAFE.putObject(this, FIELDS_OFFSET, h);
    
}

    
private void readObjectNoData()
        
throws ObjectStreamException
    
{
        
throw new InvalidObjectException("Stream data required");
    
}

    
private static final long FIELDS_OFFSET;
    
private static final sun.misc.Unsafe UNSAFE;
    
static {
        
try {
            
sun.misc.Unsafe unsafe = sun.misc.Unsafe.getUnsafe();
            
FIELDS_OFFSET = unsafe.objectFieldOffset(
                    
InetSocketAddress.class.getDeclaredField("holder"));
            
UNSAFE = unsafe;
        
} catch (ReflectiveOperationException e) {
            
throw new Error(e);
        
}
    
}

    
/**
     
* Gets the port number.
     
*
     
* @return the port number.
     
*/
    
public final int getPort() {
        
return holder.getPort();
    
}

    
/**
     
*
     
* Gets the {@code InetAddress}.
     
*
     
* @return the InetAdress or {@code null} if it is unresolved.
     
*/

    
public final InetAddress getAddress() {
        
return holder.getAddress();
    
}

    
/**
     
* Gets the {@code hostname}.
     
* Note: This method may trigger a name service reverse lookup if the
     
* address was created with a literal IP address.
     
*
     
* @return
  
the hostname part of the address.
     
*/

    
public final String getHostName() {
        
return holder.getHostName();
    
}

    
/**
     
* Returns the hostname, or the String form of the address if it
     
* doesn't have a hostname (it was created using a literal).
     
* This has the benefit of <b>not</b> attempting a reverse lookup.
     
*
     
* @return the hostname, or String representation of the address.
     
* @since 1.7
     
*/

    
public final String getHostString() {
        
return holder.getHostString();
    
}

    
/**
     
* Checks whether the address has been resolved or not.
     
*
     
* @return {@code true} if the hostname couldn't be resolved into
     
*
          
an {@code InetAddress}.
     
*/

    
public final boolean isUnresolved() {
        
return holder.isUnresolved();
    
}

    
/**
     
* Constructs a string representation of this InetSocketAddress.
     
* This String is constructed by calling toString() on the InetAddress
     
* and concatenating the port number (with a colon). If the address
     
* is unresolved then the part before the colon will only contain the hostname.
     
*
     
* @return
  
a string representation of this object.
     
*/

    
@Override
    
public String toString() {
        
return holder.toString();
    
}

    
/**
     
* 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 address as
     
* this object.
     
* <p>
     
* Two instances of {@code InetSocketAddress} represent the same
     
* address if both the InetAddresses (or hostnames if it is unresolved) and port
     
* numbers are equal.
     
* If both addresses are unresolved, then the hostname and the port number
     
* are compared.
     
*
     
* Note: Hostnames are case insensitive. e.g. "FooBar" and "foobar" are
     
* considered equal.
     
*
     
* @param
   
objthe object to compare against.
     
* @return
  
{@code true} if the objects are the same;
     
*
          
{@code false} otherwise.
     
* @see java.net.InetAddress#equals(java.lang.Object)
     
*/

    
@Override
    
public final boolean equals(Object obj) {
        
if (obj == null || !(obj instanceof InetSocketAddress))
            
return false;
        
return holder.equals(((InetSocketAddress) obj).holder);
    
}

    
/**
     
* Returns a hashcode for this socket address.
     
*
     
* @return
  
a hash code value for this socket address.
     
*/

    
@Override
    
public final int hashCode() {
        
return holder.hashCode();
    
}
}