diff --git a/org.eclipse.example.calc.test/tst/org/eclipse/example/calc/internal/CalculatorTest.java b/org.eclipse.example.calc.test/tst/org/eclipse/example/calc/internal/CalculatorTest.java
index 031d49c..318a4b4 100644
--- a/org.eclipse.example.calc.test/tst/org/eclipse/example/calc/internal/CalculatorTest.java
+++ b/org.eclipse.example.calc.test/tst/org/eclipse/example/calc/internal/CalculatorTest.java
@@ -1,93 +1,93 @@
-/*******************************************************************************
- * Copyright (C) 2010, Matthias Sohn <matthias.sohn@sap.com>
- * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
- *
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/epl-v10.html
- *******************************************************************************/
-package org.eclipse.example.calc.internal;
-
-import static org.junit.Assert.assertEquals;
-
-import org.eclipse.example.calc.Operations;
-import org.junit.After;
-import org.junit.Test;
-
-public class CalculatorTest {
-
-	@After
-	public void tearDown() throws Exception {
-		Operations.INSTANCE.reset();
-	}
-
-	@Test
-	public void testPlus() {
-		TestTextProvider textProvider = new TestTextProvider();
-		Calculator calculator = new Calculator(textProvider);
-
-		calculator.handleButtonClick("1");
-		calculator.handleButtonClick("+");
-		calculator.handleButtonClick("2");
-		calculator.handleButtonClick("=");
-
-		assertEquals("3.0", textProvider.getDisplayText());
-	}
-
-	@Test
-	public void testTwoTimesPlus() {
-		TestTextProvider textProvider = new TestTextProvider();
-		Calculator calculator = new Calculator(textProvider);
-
-		calculator.handleButtonClick("1");
-		calculator.handleButtonClick("+");
-		calculator.handleButtonClick("2");
-		calculator.handleButtonClick("+");
-		calculator.handleButtonClick("3");
-		calculator.handleButtonClick("=");
-
-		assertEquals("6.0", textProvider.getDisplayText());
-	}
-
-	@Test
-	public void testPlusWithFraction() {
-		TestTextProvider textProvider = new TestTextProvider();
-		Calculator calculator = new Calculator(textProvider);
-
-		calculator.handleButtonClick("1");
-		calculator.handleButtonClick("+");
-		calculator.handleButtonClick("2");
-		calculator.handleButtonClick(".");
-		calculator.handleButtonClick("1");
-		calculator.handleButtonClick("=");
-
-		assertEquals("3.1", textProvider.getDisplayText());
-	}
-
-	@Test
-	public void testSquare() {
-		TestTextProvider textProvider = new TestTextProvider();
-		Calculator calculator = new Calculator(textProvider);
-
-		calculator.handleButtonClick("2");
-		calculator.handleButtonClick("x²");
-
-		assertEquals("4.0", textProvider.getDisplayText());
-	}
-
-	private static final class TestTextProvider implements TextProvider {
-
-		private String text = "0";
-
-		public void setDisplayText(String text) {
-			this.text = text;
-
-		}
-
-		public String getDisplayText() {
-			return text;
-		}
-
-	}
-}
+/*******************************************************************************
+ * Copyright (C) 2010, Matthias Sohn <matthias.sohn@sap.com>
+ * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *******************************************************************************/
+package org.eclipse.example.calc.internal;
+
+import static org.junit.Assert.assertEquals;
+
+import org.eclipse.example.calc.Operations;
+import org.junit.After;
+import org.junit.Test;
+
+public class CalculatorTest {
+
+	@After
+	public void tearDown() throws Exception {
+		Operations.INSTANCE.reset();
+	}
+
+	@Test
+	public void testPlus() {
+		TestTextProvider textProvider = new TestTextProvider();
+		Calculator calculator = new Calculator(textProvider);
+
+		calculator.handleButtonClick("1");
+		calculator.handleButtonClick("+");
+		calculator.handleButtonClick("2");
+		calculator.handleButtonClick("=");
+
+		assertEquals("3.0", textProvider.getDisplayText());
+	}
+
+	@Test
+	public void testTwoTimesPlus() {
+		TestTextProvider textProvider = new TestTextProvider();
+		Calculator calculator = new Calculator(textProvider);
+
+		calculator.handleButtonClick("1");
+		calculator.handleButtonClick("+");
+		calculator.handleButtonClick("2");
+		calculator.handleButtonClick("+");
+		calculator.handleButtonClick("3");
+		calculator.handleButtonClick("=");
+
+		assertEquals("6.0", textProvider.getDisplayText());
+	}
+
+	@Test
+	public void testPlusWithFraction() {
+		TestTextProvider textProvider = new TestTextProvider();
+		Calculator calculator = new Calculator(textProvider);
+
+		calculator.handleButtonClick("1");
+		calculator.handleButtonClick("+");
+		calculator.handleButtonClick("2");
+		calculator.handleButtonClick(".");
+		calculator.handleButtonClick("1");
+		calculator.handleButtonClick("=");
+
+		assertEquals("3.1", textProvider.getDisplayText());
+	}
+
+	@Test
+	public void testSquare() {
+		TestTextProvider textProvider = new TestTextProvider();
+		Calculator calculator = new Calculator(textProvider);
+
+		calculator.handleButtonClick("2");
+		calculator.handleButtonClick("x²");
+
+		assertEquals("4.0", textProvider.getDisplayText());
+	}
+
+	private static final class TestTextProvider implements TextProvider {
+
+		private String text = "0";
+
+		public void setDisplayText(String text) {
+			this.text = text;
+
+		}
+
+		public String getDisplayText() {
+			return text;
+		}
+
+	}
+}
diff --git a/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/Calculator.java b/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/Calculator.java
index 8d1725b..fe825b0 100644
--- a/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/Calculator.java
+++ b/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/Calculator.java
@@ -1,113 +1,113 @@
-/*******************************************************************************
- * Copyright (C) 2010, Matthias Sohn <matthias.sohn@sap.com>
- * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
- *
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/epl-v10.html
- *******************************************************************************/
-package org.eclipse.example.calc.internal;
-
-import org.eclipse.example.calc.BinaryOperation;
-import org.eclipse.example.calc.Operation;
-import org.eclipse.example.calc.Operations;
-import org.eclipse.example.calc.UnaryOperation;
-import org.eclipse.example.calc.internal.operations.Equals;
-import org.eclipse.example.calc.internal.operations.Minus;
-import org.eclipse.example.calc.internal.operations.Plus;
-import org.eclipse.example.calc.internal.operations.Square;
-
-public class Calculator {
-
-	private TextProvider textProvider;
-
-	private String cmd;
-
-	private boolean clearText;
-
-	private float value;
-
-	public static String NAME = "Simple Calculator";
-
-	public Calculator(TextProvider textProvider) {
-		this.textProvider = textProvider;
-		setupDefaultOperations();
-	}
-
-	private void setupDefaultOperations() {
-		new Equals();
-		new Minus();
-		new Plus();
-		new Square();
-	}
-
-	private void calculate(String cmdName) {
-		float curValue;
-		float newValue = 0;
-
-		// get current value of display
-		curValue = Float.parseFloat(textProvider.getDisplayText());
-
-		Operation currentOp = Operations.INSTANCE.getOperation(cmdName);
-		if ((currentOp instanceof BinaryOperation) && (cmd == null)) {
-			// if last clicked operation was binary and there is no saved
-			// operation, store it
-			cmd = cmdName;
-			setClearText(true);
-		} else {
-			// if saved command is binary perform it
-			Operation savedOp = Operations.INSTANCE.getOperation(cmd);
-			if (savedOp instanceof BinaryOperation) {
-				BinaryOperation bop = (BinaryOperation) savedOp;
-				newValue = bop.perform(value, curValue);
-			} // if current operation is unary perform it
-			else if (currentOp instanceof UnaryOperation) {
-				UnaryOperation uop = (UnaryOperation) currentOp;
-				newValue = uop.perform(curValue);
-			}
-
-			// display the result and prepare clear on next button
-			textProvider.setDisplayText("" + newValue);
-			setClearText(true);
-			if (currentOp instanceof Equals) {
-				// do not save "=" command
-				cmd = null;
-			} else if (currentOp instanceof BinaryOperation) {
-				// save binary commands as they are executed on next operation
-				cmd = cmdName;
-			} else {
-				// clear saved command
-				cmd = null;
-			}
-		}
-
-	}
-
-	private boolean isCommand(String name) {
-		return (Operations.INSTANCE.getOperation(name) != null);
-	}
-
-	public void handleButtonClick(String str) {
-		if (isCommand(str)) {
-			calculate(str);
-		} else {
-			char digit = (str.toCharArray())[0];
-			if (Character.isDigit(digit) || digit == '.') {
-				if (clearText) {
-					// save current value and clear the display
-					value = Float.parseFloat(textProvider.getDisplayText());
-					textProvider.setDisplayText("");
-					setClearText(false);
-				}
-
-				// add new digit to display
-				textProvider.setDisplayText(textProvider.getDisplayText() + digit);
-			}
-		}
-	}
-
-	public void setClearText(boolean clearText) {
-		this.clearText = clearText;
-	}
-}
+/*******************************************************************************
+ * Copyright (C) 2010, Matthias Sohn <matthias.sohn@sap.com>
+ * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *******************************************************************************/
+package org.eclipse.example.calc.internal;
+
+import org.eclipse.example.calc.BinaryOperation;
+import org.eclipse.example.calc.Operation;
+import org.eclipse.example.calc.Operations;
+import org.eclipse.example.calc.UnaryOperation;
+import org.eclipse.example.calc.internal.operations.Equals;
+import org.eclipse.example.calc.internal.operations.Minus;
+import org.eclipse.example.calc.internal.operations.Plus;
+import org.eclipse.example.calc.internal.operations.Square;
+
+public class Calculator {
+
+	private TextProvider textProvider;
+
+	private String cmd;
+
+	private boolean clearText;
+
+	private float value;
+
+	public static String NAME = "Simple Calculator";
+
+	public Calculator(TextProvider textProvider) {
+		this.textProvider = textProvider;
+		setupDefaultOperations();
+	}
+
+	private void setupDefaultOperations() {
+		new Equals();
+		new Minus();
+		new Plus();
+		new Square();
+	}
+
+	private void calculate(String cmdName) {
+		float curValue;
+		float newValue = 0;
+
+		// get current value of display
+		curValue = Float.parseFloat(textProvider.getDisplayText());
+
+		Operation currentOp = Operations.INSTANCE.getOperation(cmdName);
+		if ((currentOp instanceof BinaryOperation) && (cmd == null)) {
+			// if last clicked operation was binary and there is no saved
+			// operation, store it
+			cmd = cmdName;
+			setClearText(true);
+		} else {
+			// if saved command is binary perform it
+			Operation savedOp = Operations.INSTANCE.getOperation(cmd);
+			if (savedOp instanceof BinaryOperation) {
+				BinaryOperation bop = (BinaryOperation) savedOp;
+				newValue = bop.perform(value, curValue);
+			} // if current operation is unary perform it
+			else if (currentOp instanceof UnaryOperation) {
+				UnaryOperation uop = (UnaryOperation) currentOp;
+				newValue = uop.perform(curValue);
+			}
+
+			// display the result and prepare clear on next button
+			textProvider.setDisplayText("" + newValue);
+			setClearText(true);
+			if (currentOp instanceof Equals) {
+				// do not save "=" command
+				cmd = null;
+			} else if (currentOp instanceof BinaryOperation) {
+				// save binary commands as they are executed on next operation
+				cmd = cmdName;
+			} else {
+				// clear saved command
+				cmd = null;
+			}
+		}
+
+	}
+
+	private boolean isCommand(String name) {
+		return (Operations.INSTANCE.getOperation(name) != null);
+	}
+
+	public void handleButtonClick(String str) {
+		if (isCommand(str)) {
+			calculate(str);
+		} else {
+			char digit = (str.toCharArray())[0];
+			if (Character.isDigit(digit) || digit == '.') {
+				if (clearText) {
+					// save current value and clear the display
+					value = Float.parseFloat(textProvider.getDisplayText());
+					textProvider.setDisplayText("");
+					setClearText(false);
+				}
+
+				// add new digit to display
+				textProvider.setDisplayText(textProvider.getDisplayText() + digit);
+			}
+		}
+	}
+
+	public void setClearText(boolean clearText) {
+		this.clearText = clearText;
+	}
+}
diff --git a/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/TextProvider.java b/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/TextProvider.java
index 4a1993d..db2edb5 100644
--- a/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/TextProvider.java
+++ b/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/TextProvider.java
@@ -1,26 +1,26 @@
-/*******************************************************************************
- * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
- *
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/epl-v10.html
- *******************************************************************************/
-package org.eclipse.example.calc.internal;
-
-/**
- * Display abstraction for {@link Calculator}
- */
-public interface TextProvider {
-
-	/**
-	 * @param text the text to display on the {@link Calculator}
-	 */
-	public void setDisplayText(String text);
-
-	/**
-	 * @return the text on the display of the  {@link Calculator}
-	 */
-	public String getDisplayText();
-
-}
+/*******************************************************************************
+ * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *******************************************************************************/
+package org.eclipse.example.calc.internal;
+
+/**
+ * Display abstraction for {@link Calculator}
+ */
+public interface TextProvider {
+
+	/**
+	 * @param text the text to display on the {@link Calculator}
+	 */
+	public void setDisplayText(String text);
+
+	/**
+	 * @return the text on the display of the  {@link Calculator}
+	 */
+	public String getDisplayText();
+
+}
diff --git a/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/ui/swt/CalculatorUI.java b/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/ui/swt/CalculatorUI.java
index 2961499..a082ef3 100644
--- a/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/ui/swt/CalculatorUI.java
+++ b/org.eclipse.example.calc/src/org/eclipse/example/calc/internal/ui/swt/CalculatorUI.java
@@ -1,147 +1,147 @@
-/*******************************************************************************
- * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
- *
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/epl-v10.html
- *******************************************************************************/
-package org.eclipse.example.calc.internal.ui.swt;
-
-import org.eclipse.example.calc.Operations;
-import org.eclipse.example.calc.internal.Calculator;
-import org.eclipse.example.calc.internal.TextProvider;
-import org.eclipse.swt.SWT;
-import org.eclipse.swt.events.SelectionEvent;
-import org.eclipse.swt.events.SelectionListener;
-import org.eclipse.swt.layout.GridData;
-import org.eclipse.swt.layout.GridLayout;
-import org.eclipse.swt.widgets.Button;
-import org.eclipse.swt.widgets.Composite;
-import org.eclipse.swt.widgets.Display;
-import org.eclipse.swt.widgets.Group;
-import org.eclipse.swt.widgets.Shell;
-import org.eclipse.swt.widgets.Text;
-
-/*
- * A simple calculator featuring a SWT
- *  UI.
- */
-public class CalculatorUI implements TextProvider, SelectionListener {
-
-	private static final long serialVersionUID = 1L;
-
-	private Calculator calculator;
-
-	private Shell shell;
-
-	private Text display;
-
-	private Button[] numberButtons;
-
-	private Button[] cmdButtons;
-
-	public static void main(String[] args) {
-		Display display = new Display();
-		Shell shell = new CalculatorUI().open(display);
-		while (!shell.isDisposed()) {
-			if (!display.readAndDispatch())
-				display.sleep();
-		}
-		display.dispose();
-	}
-
-	private Shell open(Display display) {
-		shell = new Shell(display);
-		setupGUI();
-
-		shell.pack();
-		shell.open();
-		return shell;
-	}
-
-	public CalculatorUI() {
-		calculator = new Calculator(this);
-	}
-
-	private void setupGUI() {
-		shell.setText(Calculator.NAME);
-		GridLayout gridLayout = new GridLayout();
-		gridLayout.numColumns = 1;
-		gridLayout.marginHeight = gridLayout.marginWidth = 0;
-		shell.setLayout(gridLayout);
-
-		setupDisplay();
-		setupNumberButtons();
-		setupCommandButtons();
-
-	}
-
-	private void setupDisplay() {
-		GridData gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
-		display = new Text(shell, SWT.BORDER_SOLID | SWT.RIGHT);
-		display.setLayoutData(gridData);
-		display.setText("0");
-		calculator.setClearText(true);
-	}
-
-	private void setupNumberButtons() {
-		Composite numberButtonsPanel = new Composite(shell, SWT.NONE);
-		numberButtonsPanel.setLayout(new GridLayout(4, true));
-		numberButtons = new Button[11];
-
-		for (int i = 0; i < numberButtons.length - 1; i++) {
-			addNumberButton(numberButtonsPanel, i, Integer.valueOf(i)
-					.toString());
-		}
-		addNumberButton(numberButtonsPanel, 10, ".");
-	}
-
-	private void addNumberButton(Composite parent, int i, String name) {
-		numberButtons[i] = new Button(parent, SWT.PUSH);
-		numberButtons[i].setText(name);
-		numberButtons[i].addSelectionListener(this);
-	}
-
-	private void setupCommandButtons() {
-		// command buttons
-		Group cmdButtonsPanel = new Group(shell, SWT.NONE);
-		cmdButtonsPanel.setText("Operations");
-		cmdButtonsPanel.setLayout(new GridLayout(4, true));
-
-		cmdButtons = new Button[Operations.INSTANCE.size()];
-
-		// make the buttons, set ActionListener and add to panel
-		for (int i = 0; i < cmdButtons.length; i++) {
-			addCommandButton(cmdButtonsPanel, i);
-		}
-	}
-
-	private void addCommandButton(Composite parent, int i) {
-		cmdButtons[i] = new Button(parent, SWT.NONE);
-		cmdButtons[i].setText(Operations.INSTANCE.getOperationName(i));
-		cmdButtons[i].addSelectionListener(this);
-	}
-
-	@Override
-	public void widgetDefaultSelected(SelectionEvent arg0) {
-		// empty
-	}
-
-	@Override
-	public void widgetSelected(SelectionEvent event) {
-		String str = ((Button) event.getSource()).getText();
-		calculator.handleButtonClick(str);
-	}
-
-	@Override
-	public void setDisplayText(String text) {
-		display.setText(text);
-	}
-
-	@Override
-	public String getDisplayText() {
-		return display.getText();
-	}
-
-}
+/*******************************************************************************
+ * Copyright (C) 2010, Stefan Lay <stefan.lay@sap.com>
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *******************************************************************************/
+package org.eclipse.example.calc.internal.ui.swt;
+
+import org.eclipse.example.calc.Operations;
+import org.eclipse.example.calc.internal.Calculator;
+import org.eclipse.example.calc.internal.TextProvider;
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.events.SelectionEvent;
+import org.eclipse.swt.events.SelectionListener;
+import org.eclipse.swt.layout.GridData;
+import org.eclipse.swt.layout.GridLayout;
+import org.eclipse.swt.widgets.Button;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Group;
+import org.eclipse.swt.widgets.Shell;
+import org.eclipse.swt.widgets.Text;
+
+/*
+ * A simple calculator featuring a SWT
+ *  UI.
+ */
+public class CalculatorUI implements TextProvider, SelectionListener {
+
+	private static final long serialVersionUID = 1L;
+
+	private Calculator calculator;
+
+	private Shell shell;
+
+	private Text display;
+
+	private Button[] numberButtons;
+
+	private Button[] cmdButtons;
+
+	public static void main(String[] args) {
+		Display display = new Display();
+		Shell shell = new CalculatorUI().open(display);
+		while (!shell.isDisposed()) {
+			if (!display.readAndDispatch())
+				display.sleep();
+		}
+		display.dispose();
+	}
+
+	private Shell open(Display display) {
+		shell = new Shell(display);
+		setupGUI();
+
+		shell.pack();
+		shell.open();
+		return shell;
+	}
+
+	public CalculatorUI() {
+		calculator = new Calculator(this);
+	}
+
+	private void setupGUI() {
+		shell.setText(Calculator.NAME);
+		GridLayout gridLayout = new GridLayout();
+		gridLayout.numColumns = 1;
+		gridLayout.marginHeight = gridLayout.marginWidth = 0;
+		shell.setLayout(gridLayout);
+
+		setupDisplay();
+		setupNumberButtons();
+		setupCommandButtons();
+
+	}
+
+	private void setupDisplay() {
+		GridData gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
+		display = new Text(shell, SWT.BORDER_SOLID | SWT.RIGHT);
+		display.setLayoutData(gridData);
+		display.setText("0");
+		calculator.setClearText(true);
+	}
+
+	private void setupNumberButtons() {
+		Composite numberButtonsPanel = new Composite(shell, SWT.NONE);
+		numberButtonsPanel.setLayout(new GridLayout(4, true));
+		numberButtons = new Button[11];
+
+		for (int i = 0; i < numberButtons.length - 1; i++) {
+			addNumberButton(numberButtonsPanel, i, Integer.valueOf(i)
+					.toString());
+		}
+		addNumberButton(numberButtonsPanel, 10, ".");
+	}
+
+	private void addNumberButton(Composite parent, int i, String name) {
+		numberButtons[i] = new Button(parent, SWT.PUSH);
+		numberButtons[i].setText(name);
+		numberButtons[i].addSelectionListener(this);
+	}
+
+	private void setupCommandButtons() {
+		// command buttons
+		Group cmdButtonsPanel = new Group(shell, SWT.NONE);
+		cmdButtonsPanel.setText("Operations");
+		cmdButtonsPanel.setLayout(new GridLayout(4, true));
+
+		cmdButtons = new Button[Operations.INSTANCE.size()];
+
+		// make the buttons, set ActionListener and add to panel
+		for (int i = 0; i < cmdButtons.length; i++) {
+			addCommandButton(cmdButtonsPanel, i);
+		}
+	}
+
+	private void addCommandButton(Composite parent, int i) {
+		cmdButtons[i] = new Button(parent, SWT.NONE);
+		cmdButtons[i].setText(Operations.INSTANCE.getOperationName(i));
+		cmdButtons[i].addSelectionListener(this);
+	}
+
+	@Override
+	public void widgetDefaultSelected(SelectionEvent arg0) {
+		// empty
+	}
+
+	@Override
+	public void widgetSelected(SelectionEvent event) {
+		String str = ((Button) event.getSource()).getText();
+		calculator.handleButtonClick(str);
+	}
+
+	@Override
+	public void setDisplayText(String text) {
+		display.setText(text);
+	}
+
+	@Override
+	public String getDisplayText() {
+		return display.getText();
+	}
+
+}