How to show Data in JLabel and Jext Boxes java swing dynamically from properties file Without knowing data in properties file

Question

Ii am working on a module of java swing in which i want to return data into java swing textboxes and labels.

The text boxes and JLabel should be varies dynamically according to data retrieve and I don't know about the properties name and their values...but i have to retrieve data from properties file without knowing the properties name and its value into Jlabel and Jtextboxes.

...and they should be varies according to data...like property name should comes into Jlabel and its value should come into Jtextboxes...

I used set interface of collection framework so i got all data from properties file into its key and values of key...but i don't know how to show it in Jlabel And JTextBoxs

public class ConfigSwingDemo extends JFrame
 {



    private File configFile = new File("momark.properties");
    private Properties configProps;
    private JButton buttonSave = new JButton("Save");
    static List<JLabel> listOfLabels = new ArrayList<JLabel>();
    static List<JTextField> listOfTextFields = new ArrayList<JTextField>();

    public ConfigSwingDemo()
    {
        super("Properties Configuration Demo");

        setLayout(new GridBagLayout());


        GridBagConstraints constraints = new GridBagConstraints();
        constraints.gridx = 0;
        constraints.gridy = 0;
        constraints.insets = new Insets(10, 10, 5, 10);
        constraints.anchor = GridBagConstraints.WEST;
        constraints.gridy = 1;
        constraints.gridx = 0;
        constraints.gridwidth = 2;
        constraints.anchor = GridBagConstraints.CENTER;
        add(buttonSave, constraints);


        buttonSave.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent arg0) {
                try {
                    saveProperties();
                    JOptionPane.showMessageDialog(ConfigSwingDemo.this, 
                            "Properties were saved successfully!");     
                } catch (IOException ex) {
                    JOptionPane.showMessageDialog(ConfigSwingDemo.this, 
                            "Error saving properties file: " + ex.getMessage());        
                }
            }
        });

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
        setLocationRelativeTo(null);
        setVisible(true);

        try {
            loadProperties();
        } catch (IOException ex) {
            JOptionPane.showMessageDialog(this, "The momark.properties file does not exist, default properties loaded.");
        }

              Set<Object> keys = configProps.keySet();

            for(Object k:keys){
                String key = (String)k;
                System.out.println(key+": "+configProps.getProperty(key));    
            }
    }

    /////////////////
    private void loadProperties() throws IOException {
        Properties defaultProps = new Properties();
        // sets default properties

        configProps = new Properties(defaultProps);

        // loads properties from file
        InputStream inputStream = new FileInputStream(configFile);
        configProps.load(inputStream);

        inputStream.close();

    }

    private void saveProperties() throws IOException {
        //configProps.setProperty("server.url", textUrl.getText());

        OutputStream outputStream = new FileOutputStream(configFile);
        configProps.store(outputStream, "properties setttings");
        outputStream.close();
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new ConfigSwingDemo();

            }
        });

    }
}

/*output console is :

          property1 : value1

          property2 : value2

          property3 : value3

          property4 : value4

i want to show output in Jlabel and Jtext field dynamically without know properies data ..so if properties increase JLabels and Textboxes also increse according to properties*/

Answer 1

Okay, so you have a Properties in key/value pairs, assuming that the key represents the label and the value the text, you can use propertyNames to get an Enumeration and iterate over the list ... that will allow you to create the labels/fields.

    GridBagConstraints constraints = new GridBagConstraints();
    constraints.gridx = 0;
    constraints.gridy = 0;
    constraints.insets = new Insets(10, 10, 5, 10);
    constraints.anchor = GridBagConstraints.WEST;

    Set<Object> keys = configProps.keySet();
    for (Object k : keys) {
        JLabel label = new JLabel(k.toString());
        JTextField field = new JTextField(configProps.getProperty(k.toString()), 10);

        constraints.gridx = 0;
        add(label, constraints);
        constraints.gridx++;
        add(field, constraints);
        constraints.gridy++;
    }
    constraints.gridx = 0;
    constraints.gridwidth = 2;
    constraints.anchor = GridBagConstraints.CENTER;
    add(buttonSave, constraints);

But you will probably want another Map which maps the keys/labels to the fields, assuming you want to save the values back again...

public class ConfigSwingDemo extends JFrame {

    private Map<String, JTextField> fieldsMap = new HashMap<>(25);
    //...

    for (Object k : keys) {
        JLabel label = new JLabel(k.toString());
        JTextField field = new JTextField(configProps.getProperty(k.toString()), 10);
        fieldsMap.put(k.toString(), field);

Then, we you want to save the values, you could use something like...

configProps.clear();
for (String key : fieldsMap.keySet()) {
    JTextField field = fieldsMap.get(key);
    configProps.setProperty(key, field.getText());
}

To copy the values back to the Properties and save it.

Now, having said all that, I'd recommend using a JTable, as you already have a basic model (key/value pairs in the Properties), it would be a lot simpler

See How to Use Tables for more details