diff --git a/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/BasicMapsOwner.kt b/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/BasicMapsOwner.kt
new file mode 100644
index 00000000000..4aa11a21ac0
--- /dev/null
+++ b/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/BasicMapsOwner.kt
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2010-2015 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.jps.incremental
+
+import org.jetbrains.annotations.TestOnly
+import org.jetbrains.jps.incremental.storage.StorageOwner
+import org.jetbrains.kotlin.jps.incremental.storage.BasicMap
+
+open class BasicMapsOwner : StorageOwner {
+    private val maps = arrayListOf<BasicMap<*, *>>()
+
+    protected fun <K, V, M : BasicMap<K, V>> registerMap(map: M): M {
+        maps.add(map)
+        return map
+    }
+
+    override fun clean() {
+        maps.forEach { it.clean() }
+    }
+
+    override fun close() {
+        maps.forEach { it.close() }
+    }
+
+    override fun flush(memoryCachesOnly: Boolean) {
+        maps.forEach { it.flush(memoryCachesOnly) }
+    }
+
+    @TestOnly
+    public fun dump(): String = maps.map { it.dump() }.joinToString("\n\n")
+}
\ No newline at end of file
diff --git a/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt b/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt
index 3c3aa58d4d7..a5a6e5e3106 100644
--- a/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt
+++ b/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/IncrementalCacheImpl.kt
@@ -26,7 +26,6 @@ import org.jetbrains.jps.builders.storage.StorageProvider
 import org.jetbrains.jps.incremental.ModuleBuildTarget
 import org.jetbrains.jps.incremental.storage.BuildDataManager
 import org.jetbrains.jps.incremental.storage.PathStringDescriptor
-import org.jetbrains.jps.incremental.storage.StorageOwner
 import org.jetbrains.kotlin.inline.inlineFunctionsJvmNames
 import org.jetbrains.kotlin.jps.build.GeneratedJvmClass
 import org.jetbrains.kotlin.jps.build.KotlinBuilder
@@ -37,7 +36,6 @@ import org.jetbrains.kotlin.load.kotlin.header.*
 import org.jetbrains.kotlin.load.kotlin.incremental.components.IncrementalCache
 import org.jetbrains.kotlin.load.kotlin.incremental.components.JvmPackagePartProto
 import org.jetbrains.kotlin.resolve.jvm.JvmClassName
-import org.jetbrains.kotlin.resolve.jvm.JvmClassName.byInternalName
 import org.jetbrains.kotlin.serialization.jvm.BitEncoding
 import org.jetbrains.org.objectweb.asm.*
 import java.io.DataInput
@@ -56,9 +54,9 @@ public fun getCacheDirectoryName(): String =
 public class IncrementalCacheImpl(
         targetDataRoot: File,
         private val target: ModuleBuildTarget
-) : StorageOwner, IncrementalCache {
+) : BasicMapsOwner(), IncrementalCache {
     companion object {
-        val CACHE_EXTENSION = "tab"
+        val CACHE_EXTENSION = ".tab"
 
         val PROTO_MAP = "proto"
         val CONSTANTS_MAP = "constants"
@@ -75,15 +73,9 @@ public class IncrementalCacheImpl(
     }
 
     private val baseDir = File(targetDataRoot, CACHE_DIRECTORY_NAME)
-    private val maps = arrayListOf<BasicMap<*, *>>()
 
     private val String.storageFile: File
-        get() = File(baseDir, this + "." + CACHE_EXTENSION)
-
-    private fun <K, V, M : BasicMap<K, V>> registerMap(map: M): M {
-        maps.add(map)
-        return map
-    }
+        get() = File(baseDir, this + CACHE_EXTENSION)
 
     private val protoMap = registerMap(ProtoMap(PROTO_MAP.storageFile))
     private val constantsMap = registerMap(ConstantsMap(CONSTANTS_MAP.storageFile))
@@ -108,11 +100,6 @@ public class IncrementalCacheImpl(
         dependents.add(cache)
     }
 
-    @TestOnly
-    public fun dump(): String {
-        return maps.joinToString("\n\n") { it.dump() }
-    }
-
     public fun markOutputClassesDirty(removedAndCompiledSources: List<File>) {
         for (sourceFile in removedAndCompiledSources) {
             val classes = sourceToClassesMap[sourceFile]
@@ -278,19 +265,11 @@ public class IncrementalCacheImpl(
         return protoMap[JvmClassName.byInternalName(MODULE_MAPPING_FILE_NAME)]?.bytes
     }
 
-    override fun flush(memoryCachesOnly: Boolean) {
-        maps.forEach { it.flush(memoryCachesOnly) }
-    }
-
     public override fun clean() {
-        maps.forEach { it.clean() }
+        super.clean()
         cacheFormatVersion.clean()
     }
 
-    public override fun close() {
-        maps.forEach { it.close () }
-    }
-
     private inner class ProtoMap(storageFile: File) : BasicStringMap<ProtoMapValue>(storageFile, ProtoMapValueExternalizer) {
 
         public fun process(kotlinClass: LocalFileKotlinClass, isPackage: Boolean, checkChangesIsOpenPart: Boolean = true): ChangesInfo {
diff --git a/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/LookupTrackerImpl.kt b/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/LookupTrackerImpl.kt
index c65d559ece2..a7bc0eb6285 100644
--- a/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/LookupTrackerImpl.kt
+++ b/jps-plugin/src/org/jetbrains/kotlin/jps/incremental/LookupTrackerImpl.kt
@@ -17,7 +17,6 @@
 package org.jetbrains.kotlin.jps.incremental
 
 import org.jetbrains.jps.builders.storage.StorageProvider
-import org.jetbrains.jps.incremental.storage.StorageOwner
 import org.jetbrains.kotlin.incremental.components.LookupTracker
 import org.jetbrains.kotlin.incremental.components.ScopeKind
 import org.jetbrains.kotlin.jps.incremental.storage.LookupMap
@@ -27,8 +26,11 @@ object LOOKUP_TRACKER_STORAGE_PROVIDER : StorageProvider<LookupTrackerImpl>() {
     override fun createStorage(targetDataDir: File): LookupTrackerImpl = LookupTrackerImpl(targetDataDir)
 }
 
-class LookupTrackerImpl(targetDataDir: File) : LookupTracker, StorageOwner {
-    private val lookupMap = LookupMap(File(targetDataDir, "lookups.tab"))
+class LookupTrackerImpl(private val targetDataDir: File) : BasicMapsOwner(), LookupTracker {
+    private val String.storageFile: File
+        get() = File(targetDataDir, this + IncrementalCacheImpl.CACHE_EXTENSION)
+
+    private val lookupMap = registerMap(LookupMap("lookups".storageFile))
 
     override fun record(lookupContainingFile: String, lookupLine: Int?, lookupColumn: Int?, scopeFqName: String, scopeKind: ScopeKind, name: String) {
         lookupMap.add(name, scopeFqName, lookupContainingFile)