diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspectionBase.java b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspectionBase.java
new file mode 100644
index 000000000000..5f4dbd1a0d36
--- /dev/null
+++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspectionBase.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2000-2013 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 com.siyeh.ig.classlayout;
+
+import com.intellij.psi.PsiAnonymousClass;
+import com.intellij.psi.PsiClass;
+import com.intellij.psi.PsiTypeParameter;
+import com.siyeh.InspectionGadgetsBundle;
+import com.siyeh.ig.BaseInspection;
+import com.siyeh.ig.BaseInspectionVisitor;
+import org.jetbrains.annotations.NotNull;
+
+public class InnerClassOnInterfaceInspectionBase extends BaseInspection {
+  /**
+   * @noinspection PublicField
+   */
+  public boolean m_ignoreInnerInterfaces = false;
+
+  @Override
+  @NotNull
+  public String getID() {
+    return "InnerClassOfInterface";
+  }
+
+  @Override
+  @NotNull
+  public String getDisplayName() {
+    return InspectionGadgetsBundle.message(
+      "inner.class.on.interface.display.name");
+  }
+
+  @Override
+  @NotNull
+  public String buildErrorString(Object... infos) {
+    final PsiClass parentInterface = (PsiClass)infos[0];
+    final String interfaceName = parentInterface.getName();
+    return InspectionGadgetsBundle.message(
+      "inner.class.on.interface.problem.descriptor", interfaceName);
+  }
+
+  @Override
+  protected boolean buildQuickFixesOnlyForOnTheFlyErrors() {
+    return true;
+  }
+
+  @Override
+  public BaseInspectionVisitor buildVisitor() {
+    return new InnerClassOnInterfaceVisitor();
+  }
+
+  private class InnerClassOnInterfaceVisitor extends BaseInspectionVisitor {
+
+    @Override
+    public void visitClass(@NotNull PsiClass aClass) {
+      // no call to super, so that it doesn't drill down to inner classes
+      if (!aClass.isInterface() || aClass.isAnnotationType()) {
+        return;
+      }
+      final PsiClass[] innerClasses = aClass.getInnerClasses();
+      for (final PsiClass innerClass : innerClasses) {
+        if (isInnerClass(innerClass)) {
+          registerClassError(innerClass, aClass);
+        }
+      }
+    }
+
+    private boolean isInnerClass(PsiClass innerClass) {
+      if (innerClass.isEnum()) {
+        return false;
+      }
+      if (innerClass.isAnnotationType()) {
+        return false;
+      }
+      if (innerClass instanceof PsiTypeParameter ||
+          innerClass instanceof PsiAnonymousClass) {
+        return false;
+      }
+      return !(innerClass.isInterface() && m_ignoreInnerInterfaces);
+    }
+  }
+}
diff --git a/plugins/InspectionGadgets/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspection.java b/plugins/InspectionGadgets/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspection.java
index cff1d771c29c..faf2281c84f5 100644
--- a/plugins/InspectionGadgets/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspection.java
+++ b/plugins/InspectionGadgets/src/com/siyeh/ig/classlayout/InnerClassOnInterfaceInspection.java
@@ -16,37 +16,13 @@
 package com.siyeh.ig.classlayout;
 
 import com.intellij.codeInspection.ui.SingleCheckboxOptionsPanel;
-import com.intellij.psi.PsiAnonymousClass;
-import com.intellij.psi.PsiClass;
-import com.intellij.psi.PsiTypeParameter;
 import com.siyeh.InspectionGadgetsBundle;
-import com.siyeh.ig.BaseInspection;
-import com.siyeh.ig.BaseInspectionVisitor;
 import com.siyeh.ig.InspectionGadgetsFix;
 import com.siyeh.ig.fixes.MoveClassFix;
-import org.jetbrains.annotations.NotNull;
 
 import javax.swing.*;
 
-public class InnerClassOnInterfaceInspection extends BaseInspection {
-
-  /**
-   * @noinspection PublicField
-   */
-  public boolean m_ignoreInnerInterfaces = false;
-
-  @Override
-  @NotNull
-  public String getID() {
-    return "InnerClassOfInterface";
-  }
-
-  @Override
-  @NotNull
-  public String getDisplayName() {
-    return InspectionGadgetsBundle.message(
-      "inner.class.on.interface.display.name");
-  }
+public class InnerClassOnInterfaceInspection extends InnerClassOnInterfaceInspectionBase {
 
   @Override
   public JComponent createOptionsPanel() {
@@ -55,58 +31,8 @@ public class InnerClassOnInterfaceInspection extends BaseInspection {
                                           this, "m_ignoreInnerInterfaces");
   }
 
-  @Override
-  @NotNull
-  public String buildErrorString(Object... infos) {
-    final PsiClass parentInterface = (PsiClass)infos[0];
-    final String interfaceName = parentInterface.getName();
-    return InspectionGadgetsBundle.message(
-      "inner.class.on.interface.problem.descriptor", interfaceName);
-  }
-
   @Override
   protected InspectionGadgetsFix buildFix(Object... infos) {
     return new MoveClassFix();
   }
-
-  @Override
-  protected boolean buildQuickFixesOnlyForOnTheFlyErrors() {
-    return true;
-  }
-
-  @Override
-  public BaseInspectionVisitor buildVisitor() {
-    return new InnerClassOnInterfaceVisitor();
-  }
-
-  private class InnerClassOnInterfaceVisitor extends BaseInspectionVisitor {
-
-    @Override
-    public void visitClass(@NotNull PsiClass aClass) {
-      // no call to super, so that it doesn't drill down to inner classes
-      if (!aClass.isInterface() || aClass.isAnnotationType()) {
-        return;
-      }
-      final PsiClass[] innerClasses = aClass.getInnerClasses();
-      for (final PsiClass innerClass : innerClasses) {
-        if (isInnerClass(innerClass)) {
-          registerClassError(innerClass, aClass);
-        }
-      }
-    }
-
-    private boolean isInnerClass(PsiClass innerClass) {
-      if (innerClass.isEnum()) {
-        return false;
-      }
-      if (innerClass.isAnnotationType()) {
-        return false;
-      }
-      if (innerClass instanceof PsiTypeParameter ||
-          innerClass instanceof PsiAnonymousClass) {
-        return false;
-      }
-      return !(innerClass.isInterface() && m_ignoreInnerInterfaces);
-    }
-  }
 }
\ No newline at end of file