--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/truffle/com.oracle.truffle.dsl.processor/src/com/oracle/truffle/dsl/processor/LanguageRegistrationProcessor.java	Wed Jun 17 10:58:08 2015 +0200
@@ -0,0 +1,142 @@
+/*
+ * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.truffle.dsl.processor;
+
+import java.io.*;
+import java.util.*;
+
+import javax.annotation.processing.*;
+import javax.lang.model.*;
+import javax.lang.model.element.*;
+import javax.lang.model.type.*;
+import javax.tools.Diagnostic.Kind;
+import javax.tools.*;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.TruffleLanguage.Registration;
+
+@SupportedAnnotationTypes("com.oracle.truffle.api.*")
+public final class LanguageRegistrationProcessor extends AbstractProcessor {
+    private final List<TypeElement> registrations = new ArrayList<>();
+
+    @Override
+    public SourceVersion getSupportedSourceVersion() {
+        return SourceVersion.latest();
+    }
+
+    private void generateFile(List<TypeElement> languages) {
+        String filename = "META-INF/truffle/language";
+        Properties p = new Properties();
+        int cnt = 0;
+        for (TypeElement l : languages) {
+            Registration annotation = l.getAnnotation(Registration.class);
+            if (annotation == null) {
+                continue;
+            }
+            String prefix = "language" + ++cnt + ".";
+            String className = processingEnv.getElementUtils().getBinaryName(l).toString();
+            p.setProperty(prefix + "name", annotation.name());
+            p.setProperty(prefix + "version", annotation.version());
+            p.setProperty(prefix + "className", className);
+            String[] mimes = annotation.mimeType();
+            for (int i = 0; i < mimes.length; i++) {
+                p.setProperty(prefix + "mimeType." + i, mimes[i]);
+            }
+        }
+        if (cnt > 0) {
+            try {
+                FileObject file = processingEnv.getFiler().createResource(StandardLocation.CLASS_OUTPUT, "", filename, languages.toArray(new Element[0]));
+                try (OutputStream os = file.openOutputStream()) {
+                    p.store(os, "Generated by " + LanguageRegistrationProcessor.class.getName());
+                }
+            } catch (IOException e) {
+                processingEnv.getMessager().printMessage(Kind.ERROR, e.getMessage(), languages.get(0));
+            }
+        }
+    }
+
+    @Override
+    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
+        if (roundEnv.processingOver()) {
+            generateFile(registrations);
+            registrations.clear();
+            return true;
+        }
+        for (Element e : roundEnv.getElementsAnnotatedWith(Registration.class)) {
+            Registration annotation = e.getAnnotation(Registration.class);
+            if (annotation != null && e.getKind() == ElementKind.CLASS) {
+                if (!e.getModifiers().contains(Modifier.PUBLIC)) {
+                    emitError("Registered language class must be public", e);
+                    continue;
+                }
+                if (e.getEnclosingElement().getKind() != ElementKind.PACKAGE && !e.getModifiers().contains(Modifier.STATIC)) {
+                    emitError("Registered language inner-class must be static", e);
+                    continue;
+                }
+                TypeMirror truffleLang = processingEnv.getElementUtils().getTypeElement(TruffleLanguage.class.getName()).asType();
+                if (!processingEnv.getTypeUtils().isAssignable(e.asType(), truffleLang)) {
+                    emitError("Registered language class must subclass TruffleLanguage", e);
+                    continue;
+                }
+                boolean found = false;
+                for (Element mem : e.getEnclosedElements()) {
+                    if (mem.getKind() != ElementKind.CONSTRUCTOR) {
+                        continue;
+                    }
+                    ExecutableElement ee = (ExecutableElement) mem;
+                    if (ee.getParameters().size() != 1) {
+                        continue;
+                    }
+                    if (!ee.getModifiers().contains(Modifier.PUBLIC)) {
+                        continue;
+                    }
+                    TypeMirror env = processingEnv.getElementUtils().getTypeElement(TruffleLanguage.Env.class.getCanonicalName()).asType();
+                    if (processingEnv.getTypeUtils().isSameType(ee.getParameters().get(0).asType(), env)) {
+                        found = true;
+                        break;
+                    }
+                }
+                if (!found) {
+                    emitError("Language must have a public constructor accepting TruffleLanguage.Env as parameter", e);
+                    continue;
+                }
+                assertNoErrorExpected(e);
+                registrations.add((TypeElement) e);
+            }
+        }
+
+        return true;
+    }
+
+    void assertNoErrorExpected(Element e) {
+        ExpectError.assertNoErrorExpected(processingEnv, e);
+    }
+
+    void emitError(String msg, Element e) {
+        if (ExpectError.isExpectedError(processingEnv, e, msg)) {
+            return;
+        }
+        processingEnv.getMessager().printMessage(Kind.ERROR, msg, e);
+    }
+
+}