Main.java Source code

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Here is the source code for Main.java

Source

/*
Java Swing, 2nd Edition
By Marc Loy, Robert Eckstein, Dave Wood, James Elliott, Brian Cole
ISBN: 0-596-00408-7
Publisher: O'Reilly 
*/

// Main.java
//An example showing several DefaultEditorKit features. This class is designed
//to be easily extended for additional functionality.
//

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Hashtable;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.ImageIcon;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JOptionPane;
import javax.swing.JTextArea;
import javax.swing.JToolBar;
import javax.swing.text.DefaultEditorKit;
import javax.swing.text.JTextComponent;

public class Main extends JFrame {

    private Action openAction = new OpenAction();

    private Action saveAction = new SaveAction();

    private JTextComponent textComp;

    private Hashtable actionHash = new Hashtable();

    public static void main(String[] args) {
        Main editor = new Main();
        editor.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        editor.setVisible(true);
    }

    // Create an editor.
    public Main() {
        super("Swing Editor");
        textComp = createTextComponent();
        makeActionsPretty();

        Container content = getContentPane();
        content.add(textComp, BorderLayout.CENTER);
        content.add(createToolBar(), BorderLayout.NORTH);
        setJMenuBar(createMenuBar());
        setSize(320, 240);
    }

    // Create the JTextComponent subclass.
    protected JTextComponent createTextComponent() {
        JTextArea ta = new JTextArea();
        ta.setLineWrap(true);
        return ta;
    }

    // Add icons and friendly names to actions we care about.
    protected void makeActionsPretty() {
        Action a;
        a = textComp.getActionMap().get(DefaultEditorKit.cutAction);
        a.putValue(Action.SMALL_ICON, new ImageIcon("cut.gif"));
        a.putValue(Action.NAME, "Cut");

        a = textComp.getActionMap().get(DefaultEditorKit.copyAction);
        a.putValue(Action.SMALL_ICON, new ImageIcon("copy.gif"));
        a.putValue(Action.NAME, "Copy");

        a = textComp.getActionMap().get(DefaultEditorKit.pasteAction);
        a.putValue(Action.SMALL_ICON, new ImageIcon("paste.gif"));
        a.putValue(Action.NAME, "Paste");

        a = textComp.getActionMap().get(DefaultEditorKit.selectAllAction);
        a.putValue(Action.NAME, "Select All");
    }

    // Create a simple JToolBar with some buttons.
    protected JToolBar createToolBar() {
        JToolBar bar = new JToolBar();

        // Add simple actions for opening & saving.
        bar.add(getOpenAction()).setText("");
        bar.add(getSaveAction()).setText("");
        bar.addSeparator();

        // Add cut/copy/paste buttons.
        bar.add(textComp.getActionMap().get(DefaultEditorKit.cutAction)).setText("");
        bar.add(textComp.getActionMap().get(DefaultEditorKit.copyAction)).setText("");
        bar.add(textComp.getActionMap().get(DefaultEditorKit.pasteAction)).setText("");
        return bar;
    }

    // Create a JMenuBar with file & edit menus.
    protected JMenuBar createMenuBar() {
        JMenuBar menubar = new JMenuBar();
        JMenu file = new JMenu("File");
        JMenu edit = new JMenu("Edit");
        menubar.add(file);
        menubar.add(edit);

        file.add(getOpenAction());
        file.add(getSaveAction());
        file.add(new ExitAction());
        edit.add(textComp.getActionMap().get(DefaultEditorKit.cutAction));
        edit.add(textComp.getActionMap().get(DefaultEditorKit.copyAction));
        edit.add(textComp.getActionMap().get(DefaultEditorKit.pasteAction));
        edit.add(textComp.getActionMap().get(DefaultEditorKit.selectAllAction));
        return menubar;
    }

    // Subclass can override to use a different open action.
    protected Action getOpenAction() {
        return openAction;
    }

    // Subclass can override to use a different save action.
    protected Action getSaveAction() {
        return saveAction;
    }

    protected JTextComponent getTextComponent() {
        return textComp;
    }

    // ********** ACTION INNER CLASSES ********** //

    // A very simple exit action
    public class ExitAction extends AbstractAction {
        public ExitAction() {
            super("Exit");
        }

        public void actionPerformed(ActionEvent ev) {
            System.exit(0);
        }
    }

    // An action that opens an existing file
    class OpenAction extends AbstractAction {
        public OpenAction() {
            super("Open", new ImageIcon("icons/open.gif"));
        }

        // Query user for a filename and attempt to open and read the file into
        // the
        // text component.
        public void actionPerformed(ActionEvent ev) {
            JFileChooser chooser = new JFileChooser();
            if (chooser.showOpenDialog(Main.this) != JFileChooser.APPROVE_OPTION)
                return;
            File file = chooser.getSelectedFile();
            if (file == null)
                return;

            FileReader reader = null;
            try {
                reader = new FileReader(file);
                textComp.read(reader, null);
            } catch (IOException ex) {
                JOptionPane.showMessageDialog(Main.this, "File Not Found", "ERROR", JOptionPane.ERROR_MESSAGE);
            } finally {
                if (reader != null) {
                    try {
                        reader.close();
                    } catch (IOException x) {
                    }
                }
            }
        }
    }

    // An action that saves the document to a file
    class SaveAction extends AbstractAction {
        public SaveAction() {
            super("Save", new ImageIcon("icons/save.gif"));
        }

        // Query user for a filename and attempt to open and write the text
        // component's content to the file.
        public void actionPerformed(ActionEvent ev) {
            JFileChooser chooser = new JFileChooser();
            if (chooser.showSaveDialog(Main.this) != JFileChooser.APPROVE_OPTION)
                return;
            File file = chooser.getSelectedFile();
            if (file == null)
                return;

            FileWriter writer = null;
            try {
                writer = new FileWriter(file);
                textComp.write(writer);
            } catch (IOException ex) {
                JOptionPane.showMessageDialog(Main.this, "File Not Saved", "ERROR", JOptionPane.ERROR_MESSAGE);
            } finally {
                if (writer != null) {
                    try {
                        writer.close();
                    } catch (IOException x) {
                    }
                }
            }
        }
    }
}