Create declarative UI test harness (#17484)

Change-Id: I8d83830f897b50a73f2fa125d297457f7a90888c

uitest/src/com/vaadin/tests/components/DeclarativeTestUI.java

@@ -0,0 +1,175 @@
+/*
+ * Copyright 2000-2014 Vaadin Ltd.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.tests.components;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.ui.Component;
+import com.vaadin.ui.declarative.Design;
+
+/**
+ * Declarative test UI. Provides simple instantiation of HTML designs located
+ * under {@code uitest/src}. Also provides {@link OnLoad} annotation that lets
+ * you easily hook up methods to run after the UI has been created. Note: you
+ * <i>must</i> add the {@link DeclarativeUI} annotation to your subclass; not
+ * doing this will result in program failure.
+ */
+@SuppressWarnings("serial")
+public class DeclarativeTestUI extends AbstractTestUI {
+
+    private Logger logger;
+    private Component component;
+
+    /**
+     * Class marker indicating the design .html file to load
+     */
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.TYPE)
+    public static @interface DeclarativeUI {
+        String value();
+
+        /**
+         * Set this property to true if you provide an absolute path to your
+         * design; otherwise, the DeclarativeTestUI logic will look for the HTML
+         * design file under {@code vaadin_project/uitest/src/<package path>/}.
+         */
+        boolean absolutePath() default false;
+    }
+
+    /**
+     * Method marker interface indicating that a method should be run after the
+     * declarative UI has been created
+     */
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.METHOD)
+    public static @interface OnLoad {
+
+    }
+
+    /**
+     * Figure out the proper path for the HTML design file
+     */
+    private String getDesignPath() {
+        Class<?> clazz = getClass();
+        String designFilePath = null;
+        if (clazz.getAnnotation(DeclarativeUI.class).absolutePath()) {
+            designFilePath = "";
+        } else {
+            // This is rather nasty.. but it works well enough for now.
+            String userDir = System.getProperty("user.dir");
+            designFilePath = userDir + "/uitest/src/"
+                    + clazz.getPackage().getName().replace('.', '/') + "/";
+        }
+
+        String designFileName = clazz.getAnnotation(DeclarativeUI.class)
+                .value();
+
+        return designFilePath + designFileName;
+    }
+
+    private Component readDesign() throws Exception {
+        String path = getDesignPath();
+        getLogger().log(Level.INFO, "Reading design from " + path);
+
+        File file = new File(path);
+        return Design.read(new FileInputStream(file));
+    }
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        Class<?> clazz = getClass();
+
+        if (clazz.isAnnotationPresent(DeclarativeUI.class)) {
+
+            // Create component
+            try {
+                component = readDesign();
+            } catch (Exception e1) {
+                getLogger().log(Level.SEVERE, "Error reading design", e1);
+                return;
+            }
+
+            addComponent(component);
+
+            // Call on-load methods (if applicable)
+            Method[] methods = clazz.getMethods();
+            for (Method m : methods) {
+                if (m.isAnnotationPresent(OnLoad.class)) {
+                    try {
+                        m.invoke(this, (Object[]) null);
+                    } catch (IllegalAccessException e) {
+                        getLogger().log(Level.SEVERE,
+                                "Error invoking @OnLoad method", e);
+                        return;
+                    } catch (IllegalArgumentException e) {
+                        getLogger().log(Level.SEVERE,
+                                "Error invoking @OnLoad method", e);
+                        return;
+                    } catch (InvocationTargetException e) {
+                        getLogger().log(Level.SEVERE,
+                                "Error invoking @OnLoad method", e);
+                        return;
+                    }
+                }
+            }
+
+        } else {
+            throw new IllegalStateException(
+                    "Cannot find declarative UI annotation");
+        }
+    }
+
+    /**
+     * Get access to the declaratively created component. This method typecasts
+     * the component to the receiving type; if there's a mismatch between what
+     * you expect and what's written in the design, this will fail with a
+     * ClassCastException.
+     * 
+     * @return a Vaadin component
+     */
+    @SuppressWarnings("unchecked")
+    public <T extends Component> T getComponent() {
+        try {
+            return (T) component;
+        } catch (ClassCastException ex) {
+            getLogger().log(Level.SEVERE,
+                    "Component code/design type mismatch", ex);
+        }
+        return null;
+    }
+
+    /**
+     * Get access to the logger of this class
+     * 
+     * @return a Logger instance
+     */
+    protected Logger getLogger() {
+        if (logger == null) {
+            logger = Logger.getLogger(getClass().getName());
+        }
+        return logger;
+    }
+}