Generate implementations of RPC interfaces on the client side (#8278).

The current implementation still requires paintables to explicitly
initialize the generated proxy instances before using them.

1 files changed, 146 insertions, 0 deletions

diff --git a/src/com/vaadin/terminal/gwt/widgetsetutils/RpcProxyGenerator.java b/src/com/vaadin/terminal/gwt/widgetsetutils/RpcProxyGenerator.java
new file mode 100644
index 0000000000..e00b558af0
--- /dev/null
+++ b/src/com/vaadin/terminal/gwt/widgetsetutils/RpcProxyGenerator.java
@@ -0,0 +1,146 @@
+package com.vaadin.terminal.gwt.widgetsetutils;
+
+import java.io.PrintWriter;
+
+import com.google.gwt.core.ext.Generator;
+import com.google.gwt.core.ext.GeneratorContext;
+import com.google.gwt.core.ext.TreeLogger;
+import com.google.gwt.core.ext.TreeLogger.Type;
+import com.google.gwt.core.ext.UnableToCompleteException;
+import com.google.gwt.core.ext.typeinfo.JClassType;
+import com.google.gwt.core.ext.typeinfo.JMethod;
+import com.google.gwt.core.ext.typeinfo.JParameter;
+import com.google.gwt.core.ext.typeinfo.TypeOracle;
+import com.google.gwt.user.rebind.ClassSourceFileComposerFactory;
+import com.google.gwt.user.rebind.SourceWriter;
+import com.vaadin.terminal.gwt.client.ApplicationConnection;
+import com.vaadin.terminal.gwt.client.communication.ClientToServerRpc;
+import com.vaadin.terminal.gwt.client.communication.ClientToServerRpc.InitializableClientToServerRpc;
+import com.vaadin.terminal.gwt.client.communication.MethodInvocation;
+
+/**
+ * GWT generator that creates client side proxy classes for making RPC calls
+ * from the client to the server.
+ * 
+ * GWT.create() calls for interfaces extending {@link ClientToServerRpc} are
+ * affected, and a proxy implementation is created. Note that the init(...)
+ * method of the proxy must be called before the proxy is used.
+ * 
+ * @since 7.0
+ */
+public class RpcProxyGenerator extends Generator {
+    @Override
+    public String generate(TreeLogger logger, GeneratorContext ctx,
+            String requestedClassName) throws UnableToCompleteException {
+        Type logType = TreeLogger.INFO;
+
+        logger.log(TreeLogger.INFO, "Running RpcProxyGenerator", null);
+
+        TypeOracle typeOracle = ctx.getTypeOracle();
+        assert (typeOracle != null);
+
+        JClassType requestedType = typeOracle.findType(requestedClassName);
+        if (requestedType == null) {
+            logger.log(TreeLogger.ERROR, "Unable to find metadata for type '"
+                    + requestedClassName + "'", null);
+            throw new UnableToCompleteException();
+        }
+
+        String generatedClassName = "ClientToServerRpc_"
+                + requestedType.getName().replaceAll("[$.]", "_");
+
+        JClassType initializableInterface = typeOracle
+                .findType(InitializableClientToServerRpc.class
+                        .getCanonicalName());
+
+        ClassSourceFileComposerFactory composer = new ClassSourceFileComposerFactory(
+                requestedType.getPackage().getName(), generatedClassName);
+        // composer.setSuperclass(requestedType.getQualifiedSourceName());
+        composer.addImplementedInterface(requestedType.getQualifiedSourceName());
+        composer.addImplementedInterface(initializableInterface
+                .getQualifiedSourceName());
+        composer.addImport(MethodInvocation.class.getCanonicalName());
+
+        logger.log(logType,
+                "Generating client proxy for remote service interface '"
+                        + requestedType.getQualifiedSourceName() + "'");
+        PrintWriter printWriter = ctx.tryCreate(logger,
+                composer.getCreatedPackage(),
+                composer.getCreatedClassShortName());
+        if (printWriter != null) {
+            SourceWriter writer = composer.createSourceWriter(ctx, printWriter);
+
+            // constructor
+            writer.println("public " + generatedClassName + "() {}");
+
+            // initialization etc.
+            writeCommonFieldsAndMethods(logger, writer, typeOracle);
+
+            // actual proxy methods forwarding calls to the server
+            writeRemoteProxyMethods(logger, writer, typeOracle, requestedType
+                    .isClassOrInterface().getMethods());
+
+            // End of class
+            writer.outdent();
+            writer.println("}");
+
+            ctx.commit(logger, printWriter);
+        }
+
+        return composer.getCreatedClassName();
+    }
+
+    private void writeCommonFieldsAndMethods(TreeLogger logger,
+            SourceWriter writer, TypeOracle typeOracle) {
+        JClassType applicationConnectionClass = typeOracle
+                .findType(ApplicationConnection.class.getCanonicalName());
+
+        // fields
+        writer.println("private String paintableId;");
+        writer.println("private "
+                + applicationConnectionClass.getQualifiedSourceName()
+                + " client;");
+
+        // init method from the RPC interface
+        writer.println("public void initRpc(String paintableId, "
+                + applicationConnectionClass.getQualifiedSourceName()
+                + " client) {");
+        writer.indent();
+
+        writer.println("this.paintableId = paintableId;");
+        writer.println("this.client = client;");
+
+        writer.outdent();
+        writer.println("}");
+    }
+
+    private static void writeRemoteProxyMethods(TreeLogger logger,
+            SourceWriter writer, TypeOracle typeOracle, JMethod[] methods) {
+        for (JMethod m : methods) {
+            writer.print(m.getReadableDeclaration(false, false, false, false,
+                    true));
+            writer.println(" {");
+            writer.indent();
+
+            writer.print("client.addMethodInvocationToQueue(new MethodInvocation(paintableId, \"");
+            writer.print(m.getName());
+            writer.print("\", new Object[] {");
+            // new Object[] { ... } for parameters - autoboxing etc. by the
+            // compiler
+            JParameter[] parameters = m.getParameters();
+            boolean first = true;
+            for (JParameter p : parameters) {
+                if (!first) {
+                    writer.print(", ");
+                }
+                first = false;
+
+                writer.print(p.getName());
+            }
+            writer.println("}), true);");
+
+            writer.outdent();
+            writer.println("}");
+        }
+    }
+}