1 files changed, 115 insertions, 0 deletions
diff --git a/src/com/vaadin/terminal/JavaScriptCallbackHelper.java b/src/com/vaadin/terminal/JavaScriptCallbackHelper.java
new file mode 100644
index 0000000000..01db0267d9
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+++ b/src/com/vaadin/terminal/JavaScriptCallbackHelper.java
@@ -0,0 +1,115 @@
+/* 
+@VaadinApache2LicenseForJavaFiles@
+ */
+
+package com.vaadin.terminal;
+
+import java.io.Serializable;
+import java.lang.reflect.Method;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+import com.vaadin.external.json.JSONArray;
+import com.vaadin.external.json.JSONException;
+import com.vaadin.terminal.gwt.client.JavaScriptConnectorHelper;
+import com.vaadin.terminal.gwt.client.JavaScriptConnectorHelper.JavaScriptConnectorState;
+import com.vaadin.tools.ReflectTools;
+import com.vaadin.ui.AbstractJavaScriptComponent;
+import com.vaadin.ui.JavaScript.JavaScriptCallbackRpc;
+import com.vaadin.ui.JavaScriptCallback;
+
+/**
+ * Internal helper class used to implement functionality common to
+ * {@link AbstractJavaScriptComponent} and {@link AbstractJavaScriptExtension}.
+ * Corresponding support in client-side code is in
+ * {@link JavaScriptConnectorHelper}.
+ * <p>
+ * You should most likely no use this class directly.
+ * 
+ * @author Vaadin Ltd
+ * @version @VERSION@
+ * @since 7.0.0
+ */
+public class JavaScriptCallbackHelper implements Serializable {
+
+    private static final Method CALL_METHOD = ReflectTools.findMethod(
+            JavaScriptCallbackRpc.class, "call", String.class, JSONArray.class);
+    private AbstractClientConnector connector;
+
+    private Map<String, JavaScriptCallback> callbacks = new HashMap<String, JavaScriptCallback>();
+    private JavaScriptCallbackRpc javascriptCallbackRpc;
+
+    public JavaScriptCallbackHelper(AbstractClientConnector connector) {
+        this.connector = connector;
+    }
+
+    public void registerCallback(String functionName,
+            JavaScriptCallback javaScriptCallback) {
+        callbacks.put(functionName, javaScriptCallback);
+        JavaScriptConnectorState state = getConnectorState();
+        if (state.getCallbackNames().add(functionName)) {
+            connector.requestRepaint();
+        }
+        ensureRpc();
+    }
+
+    private JavaScriptConnectorState getConnectorState() {
+        JavaScriptConnectorState state = (JavaScriptConnectorState) connector
+                .getState();
+        return state;
+    }
+
+    private void ensureRpc() {
+        if (javascriptCallbackRpc == null) {
+            javascriptCallbackRpc = new JavaScriptCallbackRpc() {
+                public void call(String name, JSONArray arguments) {
+                    JavaScriptCallback callback = callbacks.get(name);
+                    try {
+                        callback.call(arguments);
+                    } catch (JSONException e) {
+                        throw new IllegalArgumentException(e);
+                    }
+                }
+            };
+            connector.registerRpc(javascriptCallbackRpc);
+        }
+    }
+
+    public void invokeCallback(String name, Object... arguments) {
+        if (callbacks.containsKey(name)) {
+            throw new IllegalStateException(
+                    "Can't call callback "
+                            + name
+                            + " on the client because a callback with the same name is registered on the server.");
+        }
+        JSONArray args = new JSONArray(Arrays.asList(arguments));
+        connector.addMethodInvocationToQueue(
+                JavaScriptCallbackRpc.class.getName(), CALL_METHOD,
+                new Object[] { name, args });
+        connector.requestRepaint();
+    }
+
+    public void registerRpc(Class<?> rpcInterfaceType) {
+        if (rpcInterfaceType == JavaScriptCallbackRpc.class) {
+            // Ignore
+            return;
+        }
+        Map<String, Set<String>> rpcInterfaces = getConnectorState()
+                .getRpcInterfaces();
+        String interfaceName = rpcInterfaceType.getName();
+        if (!rpcInterfaces.containsKey(interfaceName)) {
+            Set<String> methodNames = new HashSet<String>();
+
+            for (Method method : rpcInterfaceType.getMethods()) {
+                methodNames.add(method.getName());
+            }
+
+            rpcInterfaces.put(interfaceName, methodNames);
+            connector.requestRepaint();
+        }
+    }
+
+}