ide/xml.tax/src/org/netbeans/modules/xml/tax/parser/ParsingSupport.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.netbeans.modules.xml.tax.parser;

import java.io.StringReader;
import java.io.IOException;
import java.net.URL;
import java.lang.ref.WeakReference;

import javax.swing.text.Document;

import org.xml.sax.InputSource;

import org.openide.nodes.*;  //CookieFactory
import org.openide.ErrorManager;
import org.openide.filesystems.FileObject;

import org.netbeans.tax.TreeException;
import org.netbeans.tax.TreeDocumentRoot;

/**
 * Provides support for parsing differnt sources. Subclasses must implement
 * accordingly <code>parse(InputSource)</code> method.
 *
 * @author  Petr Kuzel
 * @version 0.9
 */
public abstract class ParsingSupport {
        
    /**
     * Parse DataObject returning its model or null (on parse failure).
     */
    public abstract TreeDocumentRoot parse(InputSource in)  throws IOException, TreeException;

    
    /**
     * Converts to InputSource and pass it.
     */
    protected TreeDocumentRoot parse(TreeDocumentRoot doc) throws IOException, TreeException {
        
        return doc;
        
//        InputSource in = new InputSource();
//        in.setCharacterStream(new TreeReader(doc));
//        return parse(in);
    }

    
    /**
     * Converts to InputSource and pass it.
     */    
    protected TreeDocumentRoot parse(final Document doc) throws IOException, TreeException {
        
        InputSource in = new InputSource();
        
        // safely take the text from the document
        //??? what about DocumentReader
        
        final String[] str = new String[1];
        
        Runnable run = new Runnable() {
            public void run () {
                try {
                    str[0] = doc.getText(0, doc.getLength());
                } catch (javax.swing.text.BadLocationException e) {
                    // impossible
                    e.printStackTrace();
                }
            }
        };

        doc.render(run);
        in.setCharacterStream(new StringReader(str[0]));
        return parse(in);
    }
    
    
    /**
     * Converts to InputSource and pass it.
     */    
    protected TreeDocumentRoot parse(FileObject fo) throws IOException, TreeException{
        
        try {
            URL url = fo.toURL();
            InputSource in = new InputSource(url.toExternalForm());  //!!! we could try ti get encoding from MIME content type
            in.setByteStream(fo.getInputStream());
            return parse(in);
            
        } catch (IOException ex) {
            ErrorManager emgr = ErrorManager.getDefault();
            emgr.annotate(ex, Util.THIS.getString("MSG_can_not_create_URL"));
            emgr.notify(ex);
        }           
        return null;
    }
    
}