diff -r 000000000000 -r f2352e0b713e vm/src/main/java/org/apidesign/vm4brwsr/Variable.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vm/src/main/java/org/apidesign/vm4brwsr/Variable.java	Fri Dec 07 15:02:35 2012 +0100
@@ -0,0 +1,101 @@
+/**
+ * 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.vm4brwsr;
+
+public final class Variable implements CharSequence {
+    public static final int TYPE_INT = 0;
+    public static final int TYPE_LONG = 1;
+    public static final int TYPE_FLOAT = 2;
+    public static final int TYPE_DOUBLE = 3;
+    public static final int TYPE_REF = 4;
+
+    public static final int LAST_TYPE = TYPE_REF;
+
+    private static final String STACK_VAR_PREFIX = "st";
+
+    private final String name;
+    private final int type;
+    private final int index;
+
+    private static final char[] TYPE_IDS = { 'I', 'L', 'F', 'D', 'A' };
+
+    private Variable(final String prefix, final int type, final int index) {
+        this.name = prefix + TYPE_IDS[type] + index;
+        this.type = type;
+        this.index = index;
+    }
+
+    public static Variable getStackVariable(
+            final int type, final int index) {
+        // TODO: precreate frequently used variables
+        return new Variable(STACK_VAR_PREFIX, type, index);
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getType() {
+        return type;
+    }
+
+    public int getIndex() {
+        return index;
+    }
+
+    public boolean isCategory2() {
+        return (type == TYPE_LONG) || (type == TYPE_DOUBLE);
+    }
+
+    @Override
+    public int length() {
+        return name.length();
+    }
+
+    @Override
+    public char charAt(final int index) {
+        return name.charAt(index);
+    }
+
+    @Override
+    public CharSequence subSequence(final int start, final int end) {
+        return name.subSequence(start, end);
+    }
+
+    @Override
+    public int hashCode() {
+        return name.hashCode();
+    }
+
+    @Override
+    public boolean equals(final Object other) {
+        if (this == other) {
+            return true;
+        }
+        if (!(other instanceof Variable)) {
+            return false;
+        }
+
+        return name.equals(((Variable) other).name);
+    }
+
+    @Override
+    public String toString() {
+        return name;
+    }
+}