diff -r 000000000000 -r 58ce0cd13d26 ide/editor/src/main/java/org/apidesign/bck2brwsr/ide/editor/JNIHelper.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ide/editor/src/main/java/org/apidesign/bck2brwsr/ide/editor/JNIHelper.java	Wed Feb 13 12:08:00 2013 +0100
@@ -0,0 +1,80 @@
+/**
+ * Back 2 Browser Bytecode Translator
+ * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * This program 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. Look for COPYING file in the top folder.
+ * If not, see http://opensource.org/licenses/GPL-2.0.
+ */
+package org.apidesign.bck2brwsr.ide.editor;
+
+import java.lang.reflect.Method;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * JNI Helper.
+ * To facilitate lookup of methods by name and signature, instead of manually parsing signatures,
+ * constructs the map of all methods and uses Class.getName() to generate almost-correct signatures.
+ */
+public class JNIHelper {
+
+    static Method method(String clazz, String method, String signature) {
+        final Map<String, Method> methods = methodMap(JNIHelper.clazz(clazz));
+        return methods.get(methodKey(method, signature));
+    }
+
+    static Class<?> clazz(String clazz) {
+        try {
+            return Class.forName(clazz);
+        } catch (ClassNotFoundException e) {
+            throw new IllegalArgumentException(e);
+        }
+    }
+
+    static Map<String, Method> methodMap(final Class<?> clazz) {
+        final Map<String, Method> map = new HashMap<String, Method>();
+        final Method[] methods = clazz.getDeclaredMethods();
+        for (int i = 0; i < methods.length; i++) {
+            final Method method = methods[i];
+            map.put(methodKey(method.getName(), signature(method)), method);
+        }
+        return map;
+    }
+
+    static String methodKey(String method, String signature) {
+        return method + '@' + signature;
+    }
+
+    static String signature(final Method method) {
+        final Class<?>[] parameterTypes = method.getParameterTypes();
+        final StringBuilder b = new StringBuilder();
+        for (int j = 0; j < parameterTypes.length; j++) {
+            b.append(signature(parameterTypes[j]));
+        }
+        return b.toString();
+    }
+
+    static String signature(final Class<?> clazz) {
+        if (clazz == boolean.class) return "Z";
+        else if (clazz == byte.class) return "B";
+        else if (clazz == char.class) return "C";
+        else if (clazz == double.class) return "D";
+        else if (clazz == float.class) return "F";
+        else if (clazz == int.class) return "I";
+        else if (clazz == long.class) return "J";
+        else if (clazz == short.class) return "S";
+        else if (clazz == void.class) return "V";
+        else if (clazz.isArray()) return clazz.getName().replace('.','/');
+        else return "L" + clazz.getName().replace('.','/') + ";";
+    }
+}