diff --git a/java/java-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessor.java b/java/java-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessor.java
index efa82dfbc230..77fce0eb1366 100644
--- a/java/java-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessor.java
+++ b/java/java-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessor.java
@@ -37,7 +37,10 @@ import com.intellij.util.containers.MultiMap;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Set;
 
 import static com.intellij.util.ObjectUtils.assertNotNull;
 
@@ -140,15 +143,7 @@ public class ChangeSignatureProcessor extends ChangeSignatureProcessorBase {
       if (!processor.setupDefaultValues(myChangeInfo, refUsages, myProject)) return false;
     }
     MultiMap<PsiElement, String> conflictDescriptions = new MultiMap<PsiElement, String>();
-    for (ChangeSignatureUsageProcessor usageProcessor : ChangeSignatureUsageProcessor.EP_NAME.getExtensions()) {
-      final MultiMap<PsiElement, String> conflicts = usageProcessor.findConflicts(myChangeInfo, refUsages);
-      for (PsiElement key : conflicts.keySet()) {
-        Collection<String> collection = conflictDescriptions.get(key);
-        if (collection.size() == 0) collection = new HashSet<String>();
-        collection.addAll(conflicts.get(key));
-        conflictDescriptions.put(key, collection);
-      }
-    }
+    collectConflictsFromExtensions(refUsages, conflictDescriptions, myChangeInfo);
 
     final UsageInfo[] usagesIn = refUsages.get();
     RenameUtil.addConflictDescriptions(usagesIn, conflictDescriptions);
diff --git a/java/java-impl/src/com/intellij/refactoring/introduceparameterobject/IntroduceParameterObjectProcessor.java b/java/java-impl/src/com/intellij/refactoring/introduceparameterobject/IntroduceParameterObjectProcessor.java
index 39c943eb3020..2cd79bd89714 100644
--- a/java/java-impl/src/com/intellij/refactoring/introduceparameterobject/IntroduceParameterObjectProcessor.java
+++ b/java/java-impl/src/com/intellij/refactoring/introduceparameterobject/IntroduceParameterObjectProcessor.java
@@ -167,6 +167,7 @@ public class IntroduceParameterObjectProcessor extends FixableUsagesRefactoringP
         }
       }
     }
+    List<UsageInfo> changeSignatureUsages = new ArrayList<>();
     for (UsageInfo usageInfo : refUsages.get()) {
       if (usageInfo instanceof FixableUsageInfo) {
         final String conflictMessage = ((FixableUsageInfo)usageInfo).getConflictMessage();
@@ -174,7 +175,13 @@ public class IntroduceParameterObjectProcessor extends FixableUsagesRefactoringP
           conflicts.putValue(usageInfo.getElement(), conflictMessage);
         }
       }
+      else {
+        changeSignatureUsages.add(usageInfo);
+      }
     }
+
+    ChangeSignatureProcessorBase.collectConflictsFromExtensions(new Ref<>(changeSignatureUsages.toArray(new UsageInfo[changeSignatureUsages.size()])), conflicts, myChangeInfo);
+
     return showConflicts(conflicts, refUsages.get());
   }
 
diff --git a/platform/lang-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessorBase.java b/platform/lang-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessorBase.java
index 867e566d5cc6..d3c0f6a202bc 100644
--- a/platform/lang-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessorBase.java
+++ b/platform/lang-impl/src/com/intellij/refactoring/changeSignature/ChangeSignatureProcessorBase.java
@@ -22,6 +22,7 @@ import com.intellij.openapi.command.undo.UndoManager;
 import com.intellij.openapi.command.undo.UndoableAction;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.Ref;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiManager;
 import com.intellij.refactoring.BaseRefactoringProcessor;
@@ -36,15 +37,13 @@ import com.intellij.refactoring.util.MoveRenameUsageInfo;
 import com.intellij.usageView.UsageInfo;
 import com.intellij.util.IncorrectOperationException;
 import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.containers.MultiMap;
 import com.intellij.util.containers.hash.HashMap;
 import com.intellij.util.containers.hash.HashSet;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
+import java.util.*;
 
 /**
  * @author Maxim.Medvedev
@@ -74,6 +73,20 @@ public abstract class ChangeSignatureProcessorBase extends BaseRefactoringProces
     return findUsages(myChangeInfo);
   }
 
+  public static void collectConflictsFromExtensions(@NotNull Ref<UsageInfo[]> refUsages,
+                                                    MultiMap<PsiElement, String> conflictDescriptions,
+                                                    ChangeInfo changeInfo) {
+    for (ChangeSignatureUsageProcessor usageProcessor : ChangeSignatureUsageProcessor.EP_NAME.getExtensions()) {
+      final MultiMap<PsiElement, String> conflicts = usageProcessor.findConflicts(changeInfo, refUsages);
+      for (PsiElement key : conflicts.keySet()) {
+        Collection<String> collection = conflictDescriptions.get(key);
+        if (collection.isEmpty()) collection = new com.intellij.util.containers.HashSet<String>();
+        collection.addAll(conflicts.get(key));
+        conflictDescriptions.put(key, collection);
+      }
+    }
+  }
+
   @NotNull
   public static UsageInfo[] findUsages(ChangeInfo changeInfo) {
     List<UsageInfo> infos = new ArrayList<UsageInfo>();
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureProcessor.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureProcessor.java
index f6e340cc92da..0cab91db1a1c 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureProcessor.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureProcessor.java
@@ -22,7 +22,6 @@ import com.intellij.openapi.util.Ref;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiMethod;
 import com.intellij.refactoring.changeSignature.ChangeSignatureProcessorBase;
-import com.intellij.refactoring.changeSignature.ChangeSignatureUsageProcessor;
 import com.intellij.refactoring.changeSignature.ChangeSignatureViewDescriptor;
 import com.intellij.refactoring.rename.RenameUtil;
 import com.intellij.refactoring.ui.ConflictsDialog;
@@ -33,7 +32,6 @@ import com.intellij.util.containers.MultiMap;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Arrays;
-import java.util.Collection;
 import java.util.Set;
 
 /**
@@ -68,15 +66,7 @@ public class GrChangeSignatureProcessor extends ChangeSignatureProcessorBase {
   @Override
   protected boolean preprocessUsages(@NotNull Ref<UsageInfo[]> refUsages) {
     MultiMap<PsiElement, String> conflictDescriptions = new MultiMap<PsiElement, String>();
-    for (ChangeSignatureUsageProcessor usageProcessor : ChangeSignatureUsageProcessor.EP_NAME.getExtensions()) {
-      final MultiMap<PsiElement, String> conflicts = usageProcessor.findConflicts(myChangeInfo, refUsages);
-      for (PsiElement key : conflicts.keySet()) {
-        Collection<String> collection = conflictDescriptions.get(key);
-        if (collection.isEmpty()) collection = new HashSet<String>();
-        collection.addAll(conflicts.get(key));
-        conflictDescriptions.put(key, collection);
-      }
-    }
+    collectConflictsFromExtensions(refUsages, conflictDescriptions, myChangeInfo);
 
     final UsageInfo[] usagesIn = refUsages.get();
     RenameUtil.addConflictDescriptions(usagesIn, conflictDescriptions);