filterbuilder.java

本程序用于对页面信息进行提取并分析

        out.append ("public class ");
        out.append (name);
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("{");

        context[0] = 4;
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("public static void main (String args[])");
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("{");
        Filter.newline (out);
        
        context[0] = 8;
        names = new String [filters.length];
        for (int i = 0; i < names.length; i++)
            names[i] = filters[i].toJavaCode (out, context);

        array = "array" + context[2]++;
        Filter.spaces (out, context[0]);
        out.append ("NodeFilter[] ");
        out.append (array);
        out.append (" = new NodeFilter[");
        out.append (filters.length);
        out.append ("];");
        Filter.newline (out);
        for (int i = 0; i < filters.length; i++)
        {
            Filter.spaces (out, context[0]);
	        out.append (array);
	        out.append ("[");
	        out.append (i);
	        out.append ("] = ");
	        out.append (names[i]);
	        out.append (";");
	        Filter.newline (out);
        }

        Filter.spaces (out, context[0]);
        out.append ("FilterBean bean = new FilterBean ();");
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("bean.setFilters (");
        out.append (array);
        out.append (");");
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("if (0 != args.length)");
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("{");
        Filter.newline (out);
        context[0] = 12;
        Filter.spaces (out, context[0]);
        out.append ("bean.setURL (args[0]);");
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("System.out.println (bean.getNodes ().toHtml ());");
        Filter.newline (out);
        context[0] = 8;
        Filter.spaces (out, context[0]);
        out.append ("}");
        Filter.newline (out);
        Filter.spaces (out, context[0]);
        out.append ("else");
        Filter.newline (out);
        context[0] = 12;
        Filter.spaces (out, context[0]);
        out.append ("System.out.println (\"Usage: java -classpath .:htmlparser.jar ");
        out.append (name);
        out.append (" <url>\");");
        Filter.newline (out);
        
        context[0] = 4;
        Filter.spaces (out, context[0]);
        out.append ("}");
        Filter.newline (out);

        context[0] = 0;
        Filter.spaces (out, context[0]);
        out.append ("}");
        Filter.newline (out);
    }

    /**
     * Extracts a java class name from a file name.
     * ToDo: make this package-smart somehow.
     * @param file The name of the file.
     * @return The name of the class.
     */
    protected String classFromFile (String file)
    {
        String filesep;
        int index;

        // remove any path
        filesep = System.getProperty ("file.separator");
        index = file.lastIndexOf (filesep);
        if (-1 != index)
            file = file.substring (index + filesep.length ());
        // remove the extension
        index = file.indexOf ('.');
        if (-1 != index)
            file = file.substring (0, index);

        return (file);
    }

    /**
     * Save the workspace contents to file.
     * @param name The name of the file to save it under.
     */
    public void save (String name)
    {
        Filter[] selections;
        FilterBean bean;
        StringBuffer buffer;
        PrintWriter out;
        String ok = "OK";

        selections = getFilters ();
        if (0 != selections.length)
        {
            bean = new FilterBean ();
            bean.setURL (mURLField.getText ());
            bean.setFilters (selections);
            buffer = new StringBuffer ();
            makeProgram (classFromFile (name), buffer, bean);
            try
            {
                out = new PrintWriter (new FileWriter (name), true);
                try
                {
                    out.write (buffer.toString ());
                    out.flush ();
                }
                finally
                {
                    out.close ();
                }
            }
            catch (IOException ioe)
            {
                ioe.printStackTrace ();
            }
        }
        else // ToDo: grey out save option if nothing to save...
            JOptionPane.showOptionDialog (
                mMainPanel,
                "No filters to save.",
                "Oops",
                JOptionPane.DEFAULT_OPTION,
                JOptionPane.ERROR_MESSAGE,
                null,
                new String[] { ok },
                ok);
    }

    /**
     * The action to take when "New" menu or button pressed.
     */
    protected void newAction ()
    {
        mMainPanel.removeAll ();
        mSelection.clear ();
        relayout ();
    }

    /**
     * The action to take when "Open" menu or button pressed.
     */
    protected void openAction ()
    {
        FileDialog dialog;
        File file;

        dialog = new FileDialog (this);
        dialog.setMode (FileDialog.LOAD);
        dialog.setTitle ("Open");
        dialog.setDirectory (mHomeDir);
        dialog.setVisible (true);
        if (null != dialog.getFile ())
        {
            mHomeDir = dialog.getDirectory ();
            file = new File (mHomeDir + dialog.getFile ());
            open (file.getAbsolutePath ());
            setTitle (TITLE + " - " + file.getAbsolutePath ());
        }
    }

    /**
     * The action to take when "Save" menu or button pressed.
     */
    protected void saveAction ()
    {
        String title;
        int index;
        File file;
        FileDialog dialog;

        title = getTitle ();
        index = title.indexOf (" - ");
        if (-1 != index)
            file = new File (title.substring (index + 3));
        else
        {
            dialog = new FileDialog (this);
            dialog.setMode (FileDialog.SAVE);
            dialog.setTitle ("Save");
            dialog.setDirectory (mHomeDir);        
            dialog.setVisible (true);
	        if (null != dialog.getFile ())
	        {
	            mHomeDir = dialog.getDirectory ();
	            file = new File (mHomeDir + dialog.getFile ());
	            setTitle (TITLE + " - " + file.getAbsolutePath ());
	        }
	        else
	            file = null;
        }
        if (null != file)
            save (file.getAbsolutePath ());
    }

    /**
     * The action to take when "Save As" menu or button pressed.
     */
    protected void saveasAction ()
    {
        setTitle (TITLE);
        saveAction ();
    }

    /**
     * The action to take when "Exit" menu or button pressed.
     */
    protected void exitAction ()
    {
        exitApplication ();
    }

    /**
     * The action to take when "Cut" menu or button pressed.
     */
    protected void cutAction ()
    {
        String string;
        StringSelection contents;
        Clipboard cb;
            
        // get the selection
        string = serializeSelection ();
        // copy to clipboard
        contents = new StringSelection (string);
        cb = Toolkit.getDefaultToolkit ().getSystemClipboard ();
        cb.setContents (contents, this);
        // delete the selection
        deleteSelection ();
        relayout ();
    }

    /**
     * The action to take when "Copy" menu or button pressed.
     */
    protected void copyAction ()
    {
        String string;
        StringSelection contents;
        Clipboard cb;
            
        // get the selection
        string = serializeSelection ();
        // copy to clipboard
        contents = new StringSelection (string);
        cb = Toolkit.getDefaultToolkit ().getSystemClipboard ();
        cb.setContents (contents, this);
    }

    /**
     * The action to take when "Paste" menu or button pressed.
     */
    protected void pasteAction ()
    {
        Clipboard cb;
        Transferable content;
        String string;
        Filter[] filters;
        Point point;
        SubFilterList list;
            
        // get the text
        cb = Toolkit.getDefaultToolkit ().getSystemClipboard ();
        content = cb.getContents (this);
        if (content.isDataFlavorSupported (DataFlavor.stringFlavor))
        {
            try
            {
                string = (String)content.getTransferData (DataFlavor.stringFlavor);
                // deserialize it and add into the selection
                filters = Filter.reconstitute (string, new Parser (mURLField.getText ()));
                // add it to the (single) selected object or main panel
                if (isSingleSelection ()
                        && (null != (list = getEnclosed (getSelection ()[0]))))
                {
                    for (int i = 0; i < filters.length; i++)
                        list.addFilter (filters[i]);
                }
                else
                {
                    point = new Point (0,0);
                    for (int i = 0; i < filters.length; i++)
                    {
                        filters[i].setLocation (point);
                        mMainPanel.add (filters[i]);
                        point.y += filters[i].getPreferredSize ().height;
                    }
                }
                setupMouseListeners (filters);
                setupDropTargets (filters);
                relayout ();
            }
            catch (Exception e)
            {
                e.printStackTrace ();
            }
        }
    }

    /**
     * The action to take when "Delete" menu or button pressed.
     */
    protected void deleteAction ()
    {
        // delete the selection
        deleteSelection ();
        relayout ();
    }

    /**
     * The action to take when a filter menu or button pressed.
     */
    protected void filterAction ()
    {
        String cls;
        Filter filter;
        SubFilterList list;
        Point point;
        
        // retrieve the source component placed there by actionPerformed
        cls = mCurrentComponent.getName ();
        filter = Filter.instantiate (cls);
        // need this to get the underlying filter prepped?
        try
        {
            filter = Filter.wrap (filter.getNodeFilter (), new Parser (mURLField.getText ()));
        }
        catch (ParserException pe)
        {
            pe.printStackTrace ();
        }
        // add it to the (single) selected object or main panel
        if (isSingleSelection ()
                && (null != (list = getEnclosed (getSelection ()[0]))))
        {
            insertFilters (new Filter[] {filter}, null, list);
        }
        else
        {
            point = new Point (50,50); // find where and who to stick it into
            insertFilters (new Filter[] {filter}, point, null);
        }
    }
    
    /**
     * The action to take when "Fetch" menu pressed.
     */
    protected void fetchAction ()
    {
        JInternalFrame frame;
        Dimension dimension;
        Parser parser;
        NodeList list;

        // set up an internal frame for the results
        frame = new JInternalFrame (mURLField.getText ());