diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/MemberCodegen.java b/compiler/backend/src/org/jetbrains/kotlin/codegen/MemberCodegen.java
index ab9bc4d7c99..05628aa8213 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/MemberCodegen.java
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/MemberCodegen.java
@@ -270,7 +270,7 @@ public abstract class MemberCodegen<T extends KtElement/* TODO: & JetDeclaration
         new ImplementationBodyCodegen(aClass, classContext, classBuilder, state, parentCodegen, false).generate();
     }
 
-    private static void badDescriptor(ClassDescriptor descriptor, ClassBuilderMode mode) {
+    public static void badDescriptor(ClassDescriptor descriptor, ClassBuilderMode mode) {
         if (mode.generateBodies) {
             throw new IllegalStateException("Generating bad descriptor in ClassBuilderMode = " + mode + ": " + descriptor);
         }
diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmClassGenerator.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmClassGenerator.kt
new file mode 100644
index 00000000000..124bbeb12ca
--- /dev/null
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmClassGenerator.kt
@@ -0,0 +1,166 @@
+/*
+ * Copyright 2010-2016 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.kotlin.backend.jvm
+
+import org.jetbrains.kotlin.codegen.ClassBuilder
+import org.jetbrains.kotlin.codegen.ImplementationBodyCodegen
+import org.jetbrains.kotlin.codegen.MemberCodegen.badDescriptor
+import org.jetbrains.kotlin.codegen.OwnerKind
+import org.jetbrains.kotlin.codegen.SuperClassInfo
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.MemberDescriptor
+import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.name.SpecialNames
+import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.jvm.diagnostics.JvmDeclarationOrigin
+import org.jetbrains.kotlin.resolve.jvm.diagnostics.OtherOrigin
+import org.jetbrains.kotlin.resolve.source.PsiSourceElement
+import org.jetbrains.kotlin.types.ErrorUtils
+import org.jetbrains.org.objectweb.asm.Opcodes
+
+class JvmClassGenerator private constructor(val irClass: IrClass, context: JvmBackendContext) {
+
+    val state = context.state
+
+    val typeMapper = context.state.typeMapper
+
+    val descriptor = irClass.descriptor
+
+    val type = typeMapper.mapType(descriptor)
+
+    val visitor: ClassBuilder
+
+    init {
+        val element = (irClass.descriptor.source as PsiSourceElement).psi!!
+        visitor = state.factory.newVisitor(irClass.OtherOrigin, type, element.containingFile)
+    }
+
+    fun generate() {
+        val superClassInfo = SuperClassInfo.getSuperClassInfo(descriptor, typeMapper)
+        val signature = ImplementationBodyCodegen.signature(descriptor, type, superClassInfo, typeMapper)
+
+        visitor.defineClass(irClass.OtherOrigin.element, state.classFileVersion,
+                            descriptor.calculateClassFlags(),
+                            signature.name,
+                            signature.javaGenericSignature,
+                            signature.superclassName,
+                            signature.interfaces.toTypedArray()
+        )
+
+        irClass.declarations.forEach {
+            generateDeclaration(it)
+        }
+
+        visitor.done()
+    }
+
+    companion object {
+        fun generate(irClass: IrClass, context: JvmBackendContext) {
+            val descriptor = irClass.descriptor
+            val state = context.state
+
+            if (ErrorUtils.isError(descriptor)) {
+                badDescriptor(descriptor, state.classBuilderMode)
+                return
+            }
+
+            if (descriptor.name == SpecialNames.NO_NAME_PROVIDED) {
+                badDescriptor(descriptor, state.classBuilderMode)
+            }
+
+            JvmClassGenerator(irClass, context).generate()
+        }
+    }
+
+    fun generateDeclaration(declaration: IrDeclaration) {
+        when (declaration) {
+            is IrProperty -> {
+                declaration.backingField?.let {
+                    generateField(it)
+                }
+
+                declaration.getter?.let {
+                    generateMethod(it)
+                }
+
+                declaration.setter?.let {
+                    generateMethod(it)
+                }
+            }
+            is IrFunction -> {
+                generateMethod(declaration)
+            }
+            else -> throw RuntimeException("Unsupported declaration $declaration")
+        }
+    }
+
+
+    fun generateField(field: IrField) {
+        val fieldType = typeMapper.mapType(field.descriptor)
+        val fieldSignature = typeMapper.mapFieldSignature(field.descriptor.type, field.descriptor)
+        visitor.newField(field.OtherOrigin, field.descriptor.calculateCommonFlags(), field.descriptor.name.asString(), fieldType.descriptor,
+                         fieldSignature, null/*TODO support default values*/)
+    }
+
+    fun generateMethod(method: IrFunction) {
+        val signature = typeMapper.mapSignatureWithGeneric(method.descriptor, OwnerKind.IMPLEMENTATION)
+        visitor.newMethod(method.OtherOrigin, method.descriptor.calculateCommonFlags(), method.descriptor.name.asString(), signature.asmMethod.descriptor,
+                          signature.genericsSignature, null/*TODO support exception*/)
+    }
+
+}
+
+fun ClassDescriptor.calculateClassFlags(): Int {
+    return Opcodes.ACC_SUPER.or(calculateCommonFlags()).or(if (DescriptorUtils.isInterface(this)) Opcodes.ACC_INTERFACE else 0)
+}
+
+fun MemberDescriptor.calculateCommonFlags(): Int {
+    var flags = 0
+    if (Visibilities.isPrivate(visibility)) {
+        flags = flags.or(Opcodes.ACC_PRIVATE)
+    }
+    else if (visibility == Visibilities.PUBLIC || visibility == Visibilities.INTERNAL) {
+        flags = flags.or(Opcodes.ACC_PUBLIC)
+    }
+    else if (visibility == Visibilities.PROTECTED) {
+        flags = flags.or(Opcodes.ACC_PROTECTED)
+    }
+    else {
+        throw RuntimeException("Unsupported visibility $visibility for descriptor $this")
+    }
+
+    when (modality) {
+        Modality.ABSTRACT -> {flags = flags.or(Opcodes.ACC_ABSTRACT)}
+        Modality.FINAL -> {flags = flags.or(Opcodes.ACC_FINAL)}
+        Modality.OPEN -> {
+            assert(!Visibilities.isPrivate(visibility))
+        }
+        else -> throw RuntimeException("Unsupported modality $modality for descriptor $this")
+    }
+    return flags
+}
+
+val IrClass.OtherOrigin: JvmDeclarationOrigin
+    get() = OtherOrigin((this.descriptor.source as PsiSourceElement).psi!!, this.descriptor)
+
+val IrField.OtherOrigin: JvmDeclarationOrigin
+    get() = OtherOrigin((this.descriptor.source as PsiSourceElement).psi!!, this.descriptor)
+
+val IrFunction.OtherOrigin: JvmDeclarationOrigin
+    get() = OtherOrigin((this.descriptor.source as PsiSourceElement).psi!!, this.descriptor)
\ No newline at end of file
diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmCodegen.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmCodegen.kt
index 9d5b8bd84fa..0c1ddb38bae 100644
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmCodegen.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmCodegen.kt
@@ -20,6 +20,6 @@ import org.jetbrains.kotlin.ir.declarations.IrClass
 
 class JvmCodegen(val context: JvmBackendContext) {
     fun generateClass(irClass: IrClass) {
-        // TODO
+        JvmClassGenerator.generate(irClass, context)
     }
 }