diff -r fbf8eb98a8ef -r 5751fe604e6b javaquery/demo-calculator-dynamic/src/main/java/org/apidesign/bck2brwsr/mavenhtml/App.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/javaquery/demo-calculator-dynamic/src/main/java/org/apidesign/bck2brwsr/mavenhtml/App.java	Mon Dec 24 08:04:45 2012 +0100
@@ -0,0 +1,88 @@
+/**
+ * Back 2 Browser Bytecode Translator
+ * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. Look for COPYING file in the top folder.
+ * If not, see http://opensource.org/licenses/GPL-2.0.
+ */
+package org.apidesign.bck2brwsr.mavenhtml;
+
+import org.apidesign.bck2brwsr.htmlpage.api.OnClick;
+import org.apidesign.bck2brwsr.htmlpage.api.Page;
+
+/** HTML5 & Java demo showing the power of 
+ * <a href="http://wiki.apidesign.org/wiki/AnnotationProcessor">annotation processors</a>
+ * as well as other goodies.
+ * 
+ * @author Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+ */
+@Page(xhtml="Calculator.xhtml")
+public class App {
+    private static double memory;
+    private static String operation;
+    
+    @OnClick(id="clear")
+    static void clear() {
+        memory = 0;
+        operation = null;
+        Calculator.DISPLAY.setValue("0");
+    }
+    
+    @OnClick(id= { "plus", "minus", "mul", "div" })
+    static void applyOp(String op) {
+        memory = getValue();
+        operation = op;
+        Calculator.DISPLAY.setValue("0");
+    }
+    
+    @OnClick(id="result")
+    static void computeTheValue() {
+        switch (operation) {
+            case "plus": setValue(memory + getValue()); break;
+            case "minus": setValue(memory - getValue()); break;
+            case "mul": setValue(memory * getValue()); break;
+            case "div": setValue(memory / getValue()); break;
+            default: throw new IllegalStateException(operation);
+        }
+    }
+    
+    @OnClick(id={"n0", "n1", "n2", "n3", "n4", "n5", "n6", "n7", "n8", "n9"}) 
+    static void addDigit(String digit) {
+        digit = digit.substring(1);
+        String v = Calculator.DISPLAY.getValue();
+        if (getValue() == 0.0) {
+            Calculator.DISPLAY.setValue(digit);
+        } else {
+            Calculator.DISPLAY.setValue(v + digit);
+        }
+    }
+    
+    private static void setValue(double v) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(v);
+        if (sb.toString().endsWith(".0")) {
+            final int l = sb.length();
+            sb.delete(l - 2, l);
+        }
+        Calculator.DISPLAY.setValue(sb.toString());
+    }
+
+    private static double getValue() {
+        try {
+            return Double.parseDouble(Calculator.DISPLAY.getValue());
+        } catch (NumberFormatException ex) {
+            Calculator.DISPLAY.setValue("err");
+            return 0.0;
+        }
+    }
+}