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    <p>Here is a way to 'cheat'. All the parsing is done by the <code>ScriptEngine</code>, we just need to assemble the parts of the expression.</p> <p><img src="https://i.stack.imgur.com/OE2LU.png" alt="ScriptEngine Calculator"></p> <pre><code>import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.script.*; class ScriptEngineCalculations { public static void main(String[] args) { final ScriptEngine engine = new ScriptEngineManager(). getEngineByExtension( "js" ); String[] ops = {"+", "-", "*", "/"}; JPanel gui = new JPanel(new BorderLayout(2,2)); JPanel labels = new JPanel(new GridLayout(0,1)); gui.add(labels, BorderLayout.WEST); labels.add(new JLabel("a")); labels.add(new JLabel("operand")); labels.add(new JLabel("b")); labels.add(new JLabel("=")); JPanel controls = new JPanel(new GridLayout(0,1)); gui.add(controls, BorderLayout.CENTER); final JTextField a = new JTextField(10); controls.add(a); final JComboBox operand = new JComboBox(ops); controls.add(operand); final JTextField b = new JTextField(10); controls.add(b); final JTextField output = new JTextField(10); controls.add(output); ActionListener al = new ActionListener(){ public void actionPerformed(ActionEvent ae) { String expression = a.getText() + operand.getSelectedItem() + b.getText(); try { Object result = engine.eval(expression); if (result==null) { output.setText( "Output was 'null'" ); } else { output.setText( result.toString() ); } } catch(ScriptException se) { output.setText( se.getMessage() ); } } }; // do the calculation on event. operand.addActionListener(al); a.addActionListener(al); b.addActionListener(al); JOptionPane.showMessageDialog(null, gui); } } </code></pre> <h2>See Also</h2> <ul> <li>The <a href="http://download.oracle.com/javase/6/docs/api/javax/script/package-summary.html" rel="nofollow noreferrer"><code>javax.script</code> package</a></li> <li>The <a href="http://download.oracle.com/javase/6/docs/api/javax/script/ScriptEngine.html" rel="nofollow noreferrer"><code>ScriptEngine</code></a></li> <li>My <a href="http://pscode.org/jse.html" rel="nofollow noreferrer"><code>ScriptEngine</code> demo.</a> for exploring the capabilities of the JS engine.</li> </ul>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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