ONOS checkin based on commit tag e796610b1f721d02f9b0e213cf6f7790c10ecd60

Change-Id: Ife8810491034fe7becdba75dda20de4267bd15cd

1 files changed, 200 insertions, 0 deletions

diff --git a/framework/src/onos/core/api/src/main/java/org/onosproject/ui/UiExtension.java b/framework/src/onos/core/api/src/main/java/org/onosproject/ui/UiExtension.java
new file mode 100644
index 00000000..1f5fbd48
--- /dev/null
+++ b/framework/src/onos/core/api/src/main/java/org/onosproject/ui/UiExtension.java
@@ -0,0 +1,200 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * 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 org.onosproject.ui;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * User interface extension.
+ */
+public final class UiExtension {
+
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    private static final String VIEW_PREFIX = "app/view/";
+    private static final String EMPTY = "";
+    private static final String SLASH = "/";
+    private static final String CSS_HTML = "css.html";
+    private static final String JS_HTML = "js.html";
+
+    private final ClassLoader classLoader;
+    private final String resourcePath;
+    private final List<UiView> views;
+    private final UiMessageHandlerFactory messageHandlerFactory;
+    private final UiTopoOverlayFactory topoOverlayFactory;
+
+
+    // private constructor - only the builder calls this
+    private UiExtension(ClassLoader cl, String path, List<UiView> views,
+                        UiMessageHandlerFactory mhFactory,
+                        UiTopoOverlayFactory toFactory) {
+        this.classLoader = cl;
+        this.resourcePath = path;
+        this.views = views;
+        this.messageHandlerFactory = mhFactory;
+        this.topoOverlayFactory = toFactory;
+    }
+
+
+    /**
+     * Returns input stream containing CSS inclusion statements.
+     *
+     * @return CSS inclusion statements
+     */
+    public InputStream css() {
+        return getStream(resourcePath + CSS_HTML);
+    }
+
+    /**
+     * Returns input stream containing JavaScript inclusion statements.
+     *
+     * @return JavaScript inclusion statements
+     */
+    public InputStream js() {
+        return getStream(resourcePath + JS_HTML);
+    }
+
+    /**
+     * Returns list of user interface views contributed by this extension.
+     *
+     * @return contributed view descriptors
+     */
+    public List<UiView> views() {
+        return views;
+    }
+
+    /**
+     * Returns input stream containing specified view-specific resource.
+     *
+     * @param viewId view identifier
+     * @param path   resource path, relative to the view directory
+     * @return resource input stream
+     */
+    public InputStream resource(String viewId, String path) {
+        return getStream(VIEW_PREFIX + viewId + SLASH + path);
+    }
+
+    /**
+     * Returns message handler factory, if one was defined.
+     *
+     * @return message handler factory
+     */
+    public UiMessageHandlerFactory messageHandlerFactory() {
+        return messageHandlerFactory;
+    }
+
+    /**
+     * Returns the topology overlay factory, if one was defined.
+     *
+     * @return topology overlay factory
+     */
+    public UiTopoOverlayFactory topoOverlayFactory() {
+        return topoOverlayFactory;
+    }
+
+
+    // Returns the resource input stream from the specified class-loader.
+    private InputStream getStream(String path) {
+        InputStream stream = classLoader.getResourceAsStream(path);
+        if (stream == null) {
+            log.warn("Unable to find resource {}", path);
+        }
+        return stream;
+    }
+
+
+    /**
+     * UI Extension Builder.
+     */
+    public static class Builder {
+        private ClassLoader classLoader;
+
+        private String resourcePath = EMPTY;
+        private List<UiView> views = new ArrayList<>();
+        private UiMessageHandlerFactory messageHandlerFactory = null;
+        private UiTopoOverlayFactory topoOverlayFactory = null;
+
+        /**
+         * Create a builder with the given class loader.
+         * Resource path defaults to "".
+         * Views defaults to an empty list.
+         * Both Message and TopoOverlay factories default to null.
+         *
+         * @param cl    the class loader
+         * @param views list of views contributed by this extension
+         */
+        public Builder(ClassLoader cl, List<UiView> views) {
+            checkNotNull(cl, "Must provide a class loader");
+            checkArgument(views.size() > 0, "Must provide at least one view");
+            this.classLoader = cl;
+            this.views = views;
+        }
+
+        /**
+         * Set the resource path. That is, path to where the CSS and JS
+         * files are located. This value should
+         *
+         * @param path resource path
+         * @return self, for chaining
+         */
+        public Builder resourcePath(String path) {
+            this.resourcePath = path == null ? EMPTY : path + SLASH;
+            return this;
+        }
+
+        /**
+         * Sets the message handler factory for this extension.
+         *
+         * @param mhFactory message handler factory
+         * @return self, for chaining
+         */
+        public Builder messageHandlerFactory(UiMessageHandlerFactory mhFactory) {
+            this.messageHandlerFactory = mhFactory;
+            return this;
+        }
+
+        /**
+         * Sets the topology overlay factory for this extension.
+         *
+         * @param toFactory topology overlay factory
+         * @return self, for chaining
+         */
+        public Builder topoOverlayFactory(UiTopoOverlayFactory toFactory) {
+            this.topoOverlayFactory = toFactory;
+            return this;
+        }
+
+        /**
+         * Builds the UI extension.
+         *
+         * @return UI extension instance
+         */
+        public UiExtension build() {
+            return new UiExtension(classLoader, resourcePath, views,
+                                   messageHandlerFactory, topoOverlayFactory);
+        }
+
+    }
+
+}