/*
* @(#)DNSNameAttribute.java
*
* Copyright 2005 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistribution of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistribution in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
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*
* You acknowledge that this software is not designed or intended for use in
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*/
package com.sun.xacml.attr;
import java.net.URI;
import org.w3c.dom.DOMException;
import org.w3c.dom.Node;
import com.sun.xacml.ParsingException;
/**
* Represents the DNSName datatype introduced in XACML 2.0. All objects of
* this class are immutable and all methods of the class are thread-safe.
*
* @since 2.0
* @author Seth Proctor
*/
public class DNSNameAttribute extends AttributeValue
{
/**
* Official name of this type
*/
public static final String identifier =
TypeIdentifierConstants.DNSNAME;
/**
* URI version of name for this type
* <p>
* This field is initialized by a static initializer so that
* we can catch any exceptions thrown by URI(String) and
* transform them into a RuntimeException, since this should
* never happen but should be reported properly if it ever does.
*/
private static URI identifierURI;
/**
* RuntimeException that wraps an Exception thrown during the
* creation of identifierURI, null if none.
*/
private static RuntimeException earlyException;
/**
* Static initializer that initializes the identifierURI
* class field so that we can catch any exceptions thrown
* by URI(String) and transform them into a RuntimeException.
* Such exceptions should never happen but should be reported
* properly if they ever do.
*/
static {
try {
identifierURI = new URI(identifier);
} catch (Exception e) {
earlyException = new IllegalArgumentException();
earlyException.initCause(e);
}
}
// the required hostname
private String hostname;
// the optional port range
private PortRange range;
// true if the hostname starts with a '*'
private boolean isSubdomain = false;
/**
* Creates the new <code>DNSNameAttribute</code> with only the required
* hostname component.
*
* @param hostname the host name component of the address
*/
public DNSNameAttribute(String hostname) {
this(hostname, new PortRange());
}
/**
* Creates the new <code>DNSNameAttribute</code> with the optional
* port range component.
*
* @param hostname the host name component of the address
* @param range the port range
*/
public DNSNameAttribute(String hostname, PortRange range) {
super(identifierURI);
// shouldn't happen, but just in case...
if (earlyException != null) {
throw earlyException;
}
// verify that the hostname is valid before we store it
if (! isValidHostName(hostname)) {
System.err.println("FIXME: throw error about bad hostname");
}
// see if it started with a '*' character
if (hostname.charAt(0) == '*') {
this.isSubdomain = true;
}
this.hostname = hostname;
this.range = range;
}
/**
* Private helper that tests whether the given string is valid.
*/
private boolean isValidHostName(String hostname) {
/*
hostname = *( domainlabel "." ) toplabel [ "." ]
domainlabel = alphanum | alphanum *( alphanum | "-" ) alphanum
toplabel = alpha | alpha *( alphanum | "-" ) alphanum
*/
String domainlabel = "\\w[[\\w|\\-]*\\w]?";
String toplabel = "[a-zA-Z][[\\w|\\-]*\\w]?";
String pattern = "[\\*\\.]?[" + domainlabel + "\\.]*" + toplabel +
"\\.?";
return hostname.matches(pattern);
}
/**
* Returns a new <code>DNSNameAttribute</code> that represents
* the name at a particular DOM node.
*
* @param root the <code>Node</code> that contains the desired value
*
* @return a new <code>DNSNameAttribute</code> representing the
* appropriate value (null if there is a parsing error)
* @throws ParsingException
* @throws DOMException
*/
public static DNSNameAttribute getInstance(Node root)
throws DOMException, ParsingException {
if (root.getFirstChild() != null) {
return getInstance(root.getFirstChild().getNodeValue());
}
throw new ParsingException("Error while parsing"
+ "a DNSNameAttribute");
}
/**
* Returns a new <code>DNSNameAttribute</code> that represents
* the name indicated by the <code>String</code> provided.
*
* @param value a string representing the name
*
* @return a new <code>DNSNameAttribute</code>
* @throws ParsingException
*/
public static DNSNameAttribute getInstance(String value)
throws ParsingException {
if (value == null) {
throw new ParsingException("Can't create a "
+ "DNSNameAttribute from null input");
}
int portSep = value.indexOf(':');
if (portSep == -1) {
// there is no port range, so just use the name
return new DNSNameAttribute(value);
}
// split the name and the port range
String hostname = value.substring(0, portSep);
PortRange range =
PortRange.getInstance(value.substring(portSep + 1,
value.length()));
return new DNSNameAttribute(hostname, range);
}
/**
* Returns the host name represented by this object.
*
* @return the host name
*/
public String getHostName() {
return this.hostname;
}
/**
* Returns the port range represented by this object which will be
* unbound if no range was specified.
*
* @return the port range
*/
public PortRange getPortRange() {
return this.range;
}
/**
* Returns true if the leading character in the hostname is a '*', and
* therefore represents a matching subdomain, or false otherwise.
*
* @return true if the name represents a subdomain, false otherwise
*/
public boolean isSubdomain() {
return this.isSubdomain;
}
/**
* Returns true if the input is an instance of this class and if its
* value equals the value contained in this class.
*
* @param o the object to compare
*
* @return true if this object and the input represent the same value
*/
public boolean equals(Object o) {
if (! (o instanceof DNSNameAttribute)) {
return false;
}
DNSNameAttribute other = (DNSNameAttribute)o;
if (! this.hostname.toUpperCase().equals(
other.hostname.toUpperCase())) {
return false;
}
if (! this.range.equals(other.range)) {
return false;
}
return true;
}
/**
* Returns the hashcode value used to index and compare this object with
* others of the same type.
*
* @return the object's hashcode value
*/
public int hashCode() {
return encode().hashCode();
}
/**
* Converts to a String representation.
*
* @return the String representation
*/
public String toString() {
return "DNSNameAttribute: \"" + encode() + "\"";
}
/**
* @return The String encoding this AttributeValue.
*/
public String encode() {
if (this.range.isUnbound()) {
return this.hostname;
}
return this.hostname + ":" + this.range.encode();
}
}