acldaoxml.java

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/*
 * XP Forum
 *
 * Copyright (c) 2002-2003 RedSoft Group.  All rights reserved.
 *
 */
package org.redsoft.forum.dao.xml;

import java.io.File;
import java.util.Hashtable;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.redsoft.forum.dao.AclDAO;
import org.redsoft.forum.security.ProtectedResource;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * AclDAO's implmentation for xml
 *
 * @@author <a href="mailto:[e-mail]">cinc</a>
 *
 * @@version $Id: AclDAOxml.java,v 1.2 2004/04/10 19:56:59 cinc Exp $
 */
public class AclDAOxml implements AclDAO{
    /**
     * A hashtable that contains protected resources
     */
    protected Hashtable protectedResourceTable = new Hashtable();

    /**
     * Constructor, read protected Resource infomation from acl-config.xml,
     * and save them to a hashtable
     *
     * @param filename        full filename of acl-config.xml
     */
    public AclDAOxml(String filename){
        int i;
        File xmlFile = new File( filename );
        Document doc = null;
        try{
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            // validate xml file by parser
            // that is: use a dtd file to validate the xml file
            dbf.setValidating(true);
            DocumentBuilder db = dbf.newDocumentBuilder();
            doc = db.parse( xmlFile );

            Element root = doc.getDocumentElement();
            NodeList nodes = root.getChildNodes();

            for (i=0; i<nodes.getLength() ; i++){
                Node node = nodes.item(i);
                if (node.getNodeName().equals( ProtectedResource.PROPERTY_PROTECTED_RESOURCE )){
                    ProtectedResource pr = parseNode(node);
                    //System.out.println (pr.getUri()+":"+pr.getDesc());
                    protectedResourceTable.put( pr.getUri(), pr );
                }
            }

        }catch(Exception e){
            System.out.println ("Error reading acl-config.xml: " + e);
        }
    }

    /**
     * Read uri and desc from a protected-resource node
     *
     * @param protectedResourceNode   node of protected resource in xml file
     */
    protected ProtectedResource parseNode(Node protectedResourceNode){
        String property, value;
        NodeList nodes = protectedResourceNode.getChildNodes();
        String uri = null;
        String desc = null;
        for (int i=0; i<nodes.getLength() ; i++){
            Node node = nodes.item(i);
            if (node.getNodeName().equals( "#text" )){
                continue;
            }
            property = node.getNodeName();
            value = node.getFirstChild().getNodeValue();
            if ( property.equals( ProtectedResource.PROPERTY_URI ) ){
                uri = value;
            }else if ( property.equals( ProtectedResource.PROPERTY_DESC ) ){
                desc = value;
            }
        }
        return new ProtectedResource(uri, desc);
    }
    /**
     * Check if a uri is a protected Resource
     *
     * @return boolean - if this uri is a protected Resource
     */
    public boolean isProtectedResource(String uri){
        return protectedResourceTable.containsKey(uri);
    }
}