package org.kxml;import java.util.*;/** Like Attribute, this class is immutable for similar reasons */public class PrefixMap {    public static final PrefixMap DEFAULT = new PrefixMap (null, "", "");    String prefix;    String namespace;    PrefixMap previous;    public PrefixMap (PrefixMap previous, String prefix, String namespace) {       	this.previous = previous;	this.prefix = prefix;	this.namespace = namespace;    }     public String getNamespace () {	return namespace;    }    public String getPrefix () {	return prefix;    }    public PrefixMap getPrevious () {	return previous;    }    /** returns the namespace associated with the given prefix,	or null, if none is assigned */    public String getNamespace (String prefix) {	PrefixMap current = this;	do {	    if (prefix.equals (current.prefix)) return current.namespace;	    current = current.previous;	}	while (current != null);	return null;    }    public String getPrefix (String namespace) {	PrefixMap current = this;		do { 	    //System.err.println ("found: "+current.namespace +"/"+ current.prefix + "/" +getNamespace (current.prefix));	    if (namespace.equals (current.namespace)		&& namespace.equals (getNamespace (current.prefix))) 		return current.prefix;	    current = current.previous;	}	while (current != null); 	return null;    }}