urlmappingsxmldao.java

sun公司的petstore,一个J2ee的示例应用程序.

/*
 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 * - Redistributions of source code must retain the above copyright
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 *
 * - 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 AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES
 * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
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 * LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE SOFTWARE,
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 * You acknowledge that Software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of
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package com.sun.j2ee.blueprints.waf.controller.web;

import org.xml.sax.InputSource;
import org.w3c.dom.Element;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;

import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.SAXException;


// jaxp 1.0.1 imports
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;

import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;

import com.sun.j2ee.blueprints.util.tracer.Debug;
import com.sun.j2ee.blueprints.waf.controller.web.URLMapping;
import com.sun.j2ee.blueprints.waf.controller.web.flow.ScreenFlowData;

/**
 * This class provides the data bindings for the screendefinitions.xml
 * and the requestmappings.xml file.
 * The data obtained is maintained by the ScreenFlowManager
 */

public class URLMappingsXmlDAO {

    // constants
    public static final String URL_MAPPING = "url-mapping";
    public static final String EVENT_MAPPING = "event-mapping";
    public static final String EXCEPTION_MAPPING = "exception-mapping";
    public static final String URL = "url";
    public static final String LANGUAGE = "language";
    public static final String TEMPLATE = "template";
    public static final String RESULT = "result";
    public static final String NEXT_SCREEN = "screen";
    public static final String PROCESSS_ACTION = "isAction";
    public static final String REQUIRES_SIGNIN = "requiresSignin";
    public static final String USE_FLOW_HANDLER = "useFlowHandler";
    public static final String FLOW_HANDLER_CLASS = "class";
    public static final String WEB_ACTION_CLASS = "web-action-class";
    public static final String EJB_ACTION_CLASS = "ejb-action-class";
    public static final String EVENT_CLASS = "event-class";
    public static final String HANDLER_RESULT = "handler-result";
    public static final String FLOW_HANDLER = "flow-handler";
    public static final String EXCEPTION_CLASS = "exception-class";
    public static final String DEFAULT_SCREEN = "default-screen";

    public static final String KEY = "key";
    public static final String VALUE= "value";
    public static final String DIRECT="direct";
    public static final String SCREEN= "screen";
    public static final String SCREEN_NAME = "screen-name";
    public static final String PARAMETER = "parameter";

    public static Element loadDocument(String location) {
        Document doc = null;
        try {
            URL url = new URL(location);
            InputSource xmlInp = new InputSource(url.openStream());

            DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder parser = docBuilderFactory.newDocumentBuilder();
            doc = parser.parse(xmlInp);
            Element root = doc.getDocumentElement();
            root.normalize();
            return root;
        } catch (SAXParseException err) {
            System.err.println ("URLMappingsXmlDAO ** Parsing error" + ", line " +
                        err.getLineNumber () + ", uri " + err.getSystemId ());
            System.err.println("URLMappingsXmlDAO error: " + err.getMessage ());
        } catch (SAXException e) {
            System.err.println("URLMappingsXmlDAO error: " + e);
        } catch (java.net.MalformedURLException mfx) {
            System.err.println("URLMappingsXmlDAO error: " + mfx);
        } catch (java.io.IOException e) {
            System.err.println("URLMappingsXmlDAO error: " + e);
        } catch (Exception pce) {
            System.err.println("URLMappingsXmlDAO error: " + pce);
        }
        return null;
    }


    public static ScreenFlowData loadScreenFlowData(String location) {
        Element root = loadDocument(location);
        HashMap exceptionMappings = getExceptionMappings(root);
        String defaultScreen  = getTagValue(root, DEFAULT_SCREEN);
        return new ScreenFlowData(exceptionMappings, defaultScreen);
    }


    public static HashMap loadRequestMappings(String location) {
        Element root = loadDocument(location);
        return getRequestMappings(root);
    }


    public static HashMap loadExceptionMappings(String location) {
        Element root = loadDocument(location);
        return getExceptionMappings(root);
    }

    public static HashMap loadEventMappings(String location) {
        Element root = loadDocument(location);
        return getEventMappings(root);
    }

    private static String getSubTagAttribute(Element root, String tagName, String subTagName, String attribute) {
        String returnString = "";
        NodeList list = root.getElementsByTagName(tagName);
        for (int loop = 0; loop < list.getLength(); loop++) {
            Node node = list.item(loop);
            if (node != null) {
                NodeList  children = node.getChildNodes();
                for (int innerLoop =0; innerLoop < children.getLength(); innerLoop++) {
                    Node  child = children.item(innerLoop);
                    if ((child != null) && (child.getNodeName() != null) && child.getNodeName().equals(subTagName) ) {
                        if (child instanceof Element) {
                            return ((Element)child).getAttribute(attribute);
                        }
                    }
                } // end inner loop
            }
        }
        return returnString;
    }

    public static HashMap getExceptionMappings(Element root) {
        HashMap exceptionMappings = new HashMap();
        NodeList list = root.getElementsByTagName(EXCEPTION_MAPPING);
        for (int loop = 0; loop < list.getLength(); loop++) {