Added BitSetUtils and method converting BitSet to int.

compiler/backend/src/org/jetbrains/jet/codegen/ImplementationBodyCodegen.java

@@ -37,6 +37,7 @@ import org.jetbrains.jet.lang.resolve.java.JvmStdlibNames;
 import org.jetbrains.jet.lang.resolve.scopes.DescriptorPredicate;
 import org.jetbrains.jet.lang.types.JetType;
 import org.jetbrains.jet.lexer.JetTokens;
+import org.jetbrains.jet.utils.BitSetUtils;
 import org.objectweb.asm.AnnotationVisitor;
 import org.objectweb.asm.MethodVisitor;
 import org.objectweb.asm.Type;
@@ -168,11 +169,16 @@ public class ImplementationBodyCodegen extends ClassBodyCodegen {
         if (signature.getKotlinGenericSignature() != null || descriptor.getVisibility() != Visibilities.PUBLIC) {
             AnnotationVisitor annotationVisitor = v.newAnnotation(myClass, JvmStdlibNames.JET_CLASS.getDescriptor(), true);
             annotationVisitor.visit(JvmStdlibNames.JET_CLASS_SIGNATURE, signature.getKotlinGenericSignature());
+            BitSet flags = new BitSet();
             if (descriptor.getVisibility() == Visibilities.INTERNAL) {
-                annotationVisitor.visit(JvmStdlibNames.JET_CLASS_FLAGS_FIELD, 1 << JvmStdlibNames.FLAG_INTERNAL_BIT);
+                flags.set(JvmStdlibNames.FLAG_INTERNAL_BIT);
             }
             else if (descriptor.getVisibility() == Visibilities.PRIVATE) {
-                annotationVisitor.visit(JvmStdlibNames.JET_CLASS_FLAGS_FIELD, 1 << JvmStdlibNames.FLAG_PRIVATE_BIT);
+                flags.set(JvmStdlibNames.FLAG_PRIVATE_BIT);
+            }
+            int flagsValue = BitSetUtils.toInt(flags);
+            if (JvmStdlibNames.FLAGS_DEFAULT_VALUE != flagsValue) {
+                annotationVisitor.visit(JvmStdlibNames.JET_CLASS_FLAGS_FIELD, flagsValue);
             }
             annotationVisitor.visitEnd();
         }

compiler/backend/src/org/jetbrains/jet/codegen/signature/kotlin/JetMethodAnnotationWriter.java

@@ -18,6 +18,7 @@ package org.jetbrains.jet.codegen.signature.kotlin;
 
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.lang.resolve.java.JvmStdlibNames;
+import org.jetbrains.jet.utils.BitSetUtils;
 import org.objectweb.asm.AnnotationVisitor;
 import org.objectweb.asm.MethodVisitor;
 
@@ -34,13 +35,7 @@ public class JetMethodAnnotationWriter {
     }
 
     public void writeFlags(BitSet flags) {
-        int flagsValue = 0;
-        for (int bit = 0; bit < flags.length(); bit++) {
-            if (flags.get(bit)) {
-                flagsValue |= (1 << bit);
-            }
-        }
-
+        int flagsValue = BitSetUtils.toInt(flags);
         if (flagsValue != JvmStdlibNames.FLAGS_DEFAULT_VALUE) {
             av.visit(JvmStdlibNames.JET_METHOD_FLAGS_FIELD, flagsValue);
         }

compiler/util/src/org/jetbrains/jet/utils/BitSetUtils.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2010-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.jet.utils;
+
+import java.util.BitSet;
+
+/**
+ * @author Evgeny Gerashchenko
+ * @since 6/14/12
+ */
+public class BitSetUtils {
+    private BitSetUtils() {
+    }
+
+    public static int toInt(BitSet bitSet) {
+        int intValue = 0;
+        for (int bit = 0; bit < bitSet.length(); bit++) {
+            if (bitSet.get(bit)) {
+                intValue |= (1 << bit);
+            }
+        }
+        return intValue;
+    }
+}