WebAppConfiguration.java

In dieser Klasse wird die Konfigurationsoberfläche für das Modul definiert. Es besteht aus einem einfachen Swing-Layout und enthält zwei Textfelder, über welche die Werte der configuration.properties Datei verändert werden können. Die Implementierung einer Konfigurationsklasse ist optional, kann also entfallen, sofern eine WebApp-Komponente keine Konfigurationsmöglichkeiten zur Verfügung stellen soll.

Die main-Methode dient lediglich der einfacheren GUI-Entwicklung, muss also nicht zwingend implementiert werden.

Listing: Beispiel WebApp – Implementierung WebAppConfiguration

package de.espirit.firstspirit.opt.examples.webapp.configuration;

import de.espirit.common.Logging;
import de.espirit.firstspirit.io.FileHandle;
import de.espirit.firstspirit.module.Configuration;
import de.espirit.firstspirit.module.WebEnvironment;
import net.java.dev.designgridlayout.DesignGridLayout;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeListener;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.*;
import java.util.List;

/**
 * Implements the configuration dialog
 */
public class WebAppConfiguration implements Configuration<WebEnvironment> {

    /**
     * name of the configuration file
     */
    public static final String CONFIGURATION_FILE = "configuration.properties";

    /**
     * name of the configuration property
     */
    public static final String PROP_ENVIRONMENT = "environment";
    public static final String PROP_COUNTER_INITAL_VALUE = "counterInitialValue";

    private final Properties _config;
    privateWebEnvironment _env;
    private JComponent _gui;

    private JTextField _environment;
    private JTextField _counterInitalValue;

    public WebAppConfiguration() {
        _config = new Properties();
    }

    public boolean hasGui() {
        return true;  // We want to have a GUI
    }

    public JComponent getGui(final Frame frame) {
        if(_gui == null) {
            final JPanel mainPanel = new JPanel();
            final DesignGridLayout layout = new DesignGridLayout(mainPanel);
            mainPanel.setOpaque(false);

            final JLabel headline1 = new JLabel("WebApp Configuration");
            final Font font = headline1.getFont();
            headline1.setFont(font.deriveFont(font.getStyle() ^ Font.BOLD));
            layout.row().left().fill().add(headline1);

            final JLabel lEnvironment = new JLabel("Environment");
            _environment = new JTextField(_config.getProperty(PROP_ENVIRONMENT));
            layout.row().grid(lEnvironment).add(_environment, 4);

            final JLabel lInitalCount = new JLabel("Counter Inital Value");
            _counterInitalValue = new TextField(_config.getProperty(
                    PROP_COUNTER_INITAL_VALUE));
            layout.row().grid(lInitalCount).add(_counterInitalValue, 4);

            _gui = mainPanel;
        }
        return _gui;
    }

    /**
     * load configuration from configuration file
     */
    public void load() {

        //set default value to PRODUCTION
        _config.setProperty(PROP_ENVIRONMENT,"PRODUCTION");
        _config.setProperty(PROP_COUNTER_INITAL_VALUE,"0");
        try {
            final FileHandle iniFile = getEnvironment().getConfDir()
                    .obtain(CONFIGURATION_FILE);
            if(iniFile.isFile()) {
                _config.load(iniFile.load());
            }
        } catch (IOException e) {
            Logging.logWarning("Couldn't load configuration file!",
                    e, WebAppConfiguration.class);
        }
        if(_gui != null) {
            _environment.setText(_config.getProperty(PROP_ENVIRONMENT));
            _counterInitalValue.setText(_config.getProperty(
                    PROP_COUNTER_INITAL_VALUE));
        }
    }

    /**
     * read values from gui and store them into the configuration file
     */
    public void store() {
        if(_gui != null) {
            _config.setProperty(PROP_ENVIRONMENT, _environment.getText());
            _config.setProperty(PROP_COUNTER_INITAL_VALUE,
                    _counterInitalValue.getText());
        }

        try {
            final ByteArrayOutputStream out = new ByteArrayOutputStream();
            _config.store(out, "FirstSpirit WebApp Example Module - Configuration");
            final FileHandle iniFile =getEnvironment().getConfDir()
                    .obtain(CONFIGURATION_FILE);
            iniFile.save(new ByteArrayInputStream(out.toByteArray()));
        } catch (IOException e) {
            Logging.logWarning("Couldn't store configuration file!",
                    e, WebAppConfiguration.class);
        }
    }

    public Set<String> getParameterNames() {
        final Set<String> result = new HashSet<String>();
        for (final Enumeration<?> names = _config.propertyNames();
                names.hasMoreElements();) {
            result.add(names.nextElement().toString());
        }
        return result;
    }

    public String getParameter(final String name) {
        return _config.getProperty(name);
    }

    public void init(final String moduleName, final String componentName,
            final WebEnvironment env) {
        _env = env;
    }

    public WebEnvironment getEnvironment() {
        return _env;
    }

    /**
     * Main method for easier gui development.
     *
     * @param args   unused.
     */
    public static void main(final String[] args) {
        final JFrame frame = new JFrame("Configuration");
        final WebAppConfiguration configurator = new WebAppConfiguration();
        final JComponent gui = configurator.getGui(frame);
        final JButton closeBtn = new JButton("Close");
        closeBtn.addActionListener(
                new ActionListener() {
                    public void actionPerformed(final ActionEvent e) {
                        frame.setVisible(false);
                        frame.dispose();
                    }
                }
                );

        frame.getContentPane().add(gui);
        frame.getRootPane().setDefaultButton(closeBtn);
        frame.setSize(580, 300);
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

}