THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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- A component implementing a dictionary service
- A component requiring the dictionary service and providing a spellchecker service
- A component requiring the spellchecker and providing an user interface
// FIGURE HERE
- !spell.png!
Preparing the tutorial
This tutorial is based on Ant. So, you need to have the Ant program accessible in your path (see here to download and install Ant). Download the tutorial archive available here and then unzip it. The archive is composed by seven directories:
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package spell.gui;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import spell.services.SpellChecker;
/**
* A very simple Gui interacting with the CheckSpeller service
*/
public class SpellCheckerGui extends JFrame {
/**
* Swing component where the user write the passage to check.
*/
private JTextField m_passage = null;
/**
* Check button
*/
private JButton m_checkButton = null;
/**
* Area where the result is displayed.
*/
private JLabel m_result = null;
/**
* Service dependency on the SpellChecker.
*/
private SpellChecker m_checker;
/**
* Constructor.
* Initialize the GUI.
*/
public SpellCheckerGui() {
super();
initComponents();
this.setTitle("Spellchecker Gui");
}
/**
* Initialize the Swing Gui.
*/
private void initComponents() {
java.awt.GridBagConstraints gridBagConstraints;
m_checkButton = new javax.swing.JButton();
m_result = new javax.swing.JLabel();
m_passage = new javax.swing.JTextField();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
getContentPane().setLayout(new java.awt.GridBagLayout());
m_checkButton.setText("Check");
m_checkButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent e) {
check();
}
});
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 1;
gridBagConstraints.insets = new java.awt.Insets(2, 2, 2, 2);
getContentPane().add(m_checkButton, gridBagConstraints);
m_result.setPreferredSize(new java.awt.Dimension(175, 20));
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 2;
gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;
gridBagConstraints.insets = new java.awt.Insets(2, 2, 2, 2);
getContentPane().add(m_result, gridBagConstraints);
m_passage.setPreferredSize(new java.awt.Dimension(175, 20));
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 0;
gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;
gridBagConstraints.insets = new java.awt.Insets(2, 2, 2, 2);
getContentPane().add(m_passage, gridBagConstraints);
pack();
}
/**
* Check Button action.
* Collects the user input and checks it.
*/
private void check() {
String[] result = m_checker.check(m_passage.getText());
if (result != null) {
m_result.setText(result.length + " word(s) are mispelled");
} else {
m_result.setText("All words are correct");
}
}
/**
* Start callback.
* This method will be called when the instance becomes valid.
* It set the Gui visibility to true.
*/
public void start() {
this.setVisible(true);
}
/**
* Stop callback.
* This method will be called when the instance becomes invalid or stops.
* It deletes the Gui.
*/
public void stop() {
this.dispose();
}
}
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When starting the GUI bundle, the user interface appears. Indeed, the Check Speller service is provided. You can interact with this service by entering a passage and clicking on the check button:
//FIGURE HERE
Then, stop the Dictionaryservice provider (with the stop 6) command. The GUI disappears. Indeed, Spell Checker service cannot be provided as it depends on the Dictionary service.
//FIGURE HERE
Then, restart the Dictionary service provider with the start 6 command. The GUI reappears immediately. You can try to stop the check speller service provider without stopping the dictionary service provider with the stop 7 command. As for the last manipulation, the GUI disappears.// FIGURE HERE
Conclusion
We saw how to use easily iPOJO to build service-oriented component. In this tutorial, we have demonstrated how to:
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