diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureConflictSearcher.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureConflictSearcher.java
new file mode 100644
index 000000000000..9ff813bd6336
--- /dev/null
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureConflictSearcher.java
@@ -0,0 +1,162 @@
+/*
+ * Copyright 2000-2010 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.plugins.groovy.refactoring.changeSignature;
+
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.util.Ref;
+import com.intellij.psi.*;
+import com.intellij.refactoring.RefactoringBundle;
+import com.intellij.refactoring.changeSignature.JavaChangeInfo;
+import com.intellij.refactoring.changeSignature.JavaParameterInfo;
+import com.intellij.refactoring.rename.RenameUtil;
+import com.intellij.refactoring.util.CanonicalTypes;
+import com.intellij.refactoring.util.ConflictsUtil;
+import com.intellij.refactoring.util.RefactoringUIUtil;
+import com.intellij.usageView.UsageInfo;
+import com.intellij.util.ArrayUtil;
+import com.intellij.util.IncorrectOperationException;
+import com.intellij.util.VisibilityUtil;
+import com.intellij.util.containers.HashSet;
+import com.intellij.util.containers.MultiMap;
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.plugins.groovy.GroovyFileType;
+import org.jetbrains.plugins.groovy.lang.psi.GroovyPsiElement;
+import org.jetbrains.plugins.groovy.lang.psi.GroovyPsiElementFactory;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.GrConstructorInvocation;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.expressions.GrExpression;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.expressions.GrReferenceExpression;
+
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.Set;
+
+/**
+* @author Maxim.Medvedev
+*/
+class GrChangeSignatureConflictSearcher {
+  private static final Logger LOG =
+    Logger.getInstance("#org.jetbrains.plugins.groovy.refactoring.changeSignature.GrChangeSignatureConflictSearcher");
+  private final JavaChangeInfo myChangeInfo;
+
+  GrChangeSignatureConflictSearcher(JavaChangeInfo changeInfo) {
+    this.myChangeInfo = changeInfo;
+  }
+
+  public MultiMap<PsiElement, String> findConflicts(Ref<UsageInfo[]> refUsages) {
+    MultiMap<PsiElement, String> conflictDescriptions = new MultiMap<PsiElement, String>();
+    addMethodConflicts(conflictDescriptions);
+    UsageInfo[] usagesIn = refUsages.get();
+    RenameUtil.addConflictDescriptions(usagesIn, conflictDescriptions);
+    Set<UsageInfo> usagesSet = new HashSet<UsageInfo>(Arrays.asList(usagesIn));
+    RenameUtil.removeConflictUsages(usagesSet);
+    if (myChangeInfo.isVisibilityChanged()) {
+      try {
+        addInaccessibilityDescriptions(usagesSet, conflictDescriptions);
+      }
+      catch (IncorrectOperationException e) {
+        LOG.error(e);
+      }
+    }
+
+    return conflictDescriptions;
+  }
+
+  private boolean needToChangeCalls() {
+    return myChangeInfo.isNameChanged() || myChangeInfo.isParameterSetOrOrderChanged() || myChangeInfo.isExceptionSetOrOrderChanged();
+  }
+
+
+  private void addInaccessibilityDescriptions(Set<UsageInfo> usages, MultiMap<PsiElement, String> conflictDescriptions)
+    throws IncorrectOperationException {
+    PsiMethod method = myChangeInfo.getMethod();
+    PsiModifierList modifierList = (PsiModifierList)method.getModifierList().copy();
+    VisibilityUtil.setVisibility(modifierList, myChangeInfo.getNewVisibility());
+
+    for (Iterator<UsageInfo> iterator = usages.iterator(); iterator.hasNext();) {
+      UsageInfo usageInfo = iterator.next();
+      PsiElement element = usageInfo.getElement();
+      if (element != null) {
+        if (element instanceof GrReferenceExpression) {
+          PsiClass accessObjectClass = null;
+          GrExpression qualifier = ((GrReferenceExpression)element).getQualifierExpression();
+          if (qualifier != null) {
+            accessObjectClass = getAccessObjectClass(qualifier);
+          }
+
+          if (!JavaPsiFacade.getInstance(element.getProject()).getResolveHelper()
+            .isAccessible(method, modifierList, element, accessObjectClass, null)) {
+            String message =
+              RefactoringBundle.message("0.with.1.visibility.is.not.accesible.from.2",
+                                        RefactoringUIUtil.getDescription(method, true),
+                                        myChangeInfo.getNewVisibility(),
+                                        RefactoringUIUtil.getDescription(ConflictsUtil.getContainer(element), true));
+            conflictDescriptions.putValue(method, message);
+            if (!needToChangeCalls()) {
+              iterator.remove();
+            }
+          }
+        }
+      }
+    }
+  }
+
+  @Nullable
+  private static PsiClass getAccessObjectClass(GrExpression expression) {
+    if (expression instanceof GrConstructorInvocation) return null;
+    PsiType type = expression.getType();
+    if (type instanceof PsiClassType) {
+      return ((PsiClassType)type).resolveGenerics().getElement();
+    }
+    if (type == null && expression instanceof PsiReferenceExpression) {
+      JavaResolveResult resolveResult = ((PsiReferenceExpression)expression).advancedResolve(false);
+      if (resolveResult.getElement() instanceof PsiClass) {
+        return (PsiClass)resolveResult.getElement();
+      }
+    }
+    return null;
+  }
+
+
+  private void addMethodConflicts(MultiMap<PsiElement, String> conflicts) {
+    String newMethodName = myChangeInfo.getNewName();
+    try {
+      PsiMethod prototype;
+      final PsiMethod method = myChangeInfo.getMethod();
+      if (!GroovyFileType.GROOVY_LANGUAGE.equals(method.getLanguage())) return;
+      PsiManager manager = PsiManager.getInstance(method.getProject());
+      GroovyPsiElementFactory factory = GroovyPsiElementFactory.getInstance(manager.getProject());
+      final CanonicalTypes.Type returnType = myChangeInfo.getNewReturnType();
+      if (returnType != null) {
+        prototype = factory.createMethodFromText("", newMethodName, returnType.getTypeText(), ArrayUtil.EMPTY_STRING_ARRAY);
+      }
+      else {
+        prototype = factory.createConstructorFromText(newMethodName, ArrayUtil.EMPTY_STRING_ARRAY, ArrayUtil.EMPTY_STRING_ARRAY, "");
+      }
+      JavaParameterInfo[] parameters = myChangeInfo.getNewParameters();
+
+
+      for (JavaParameterInfo info : parameters) {
+        PsiParameter param = factory.createParameter(info.getName(), info.getTypeText(), (GroovyPsiElement)method);
+        prototype.getParameterList().add(param);
+      }
+
+      ConflictsUtil.checkMethodConflicts(method.getContainingClass(), method, prototype, conflicts);
+    }
+    catch (IncorrectOperationException e) {
+      LOG.error(e);
+    }
+  }
+}
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureUsageProcessor.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureUsageProcessor.java
index 387cd3c97aaa..316aa8ca934b 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureUsageProcessor.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/refactoring/changeSignature/GrChangeSignatureUsageProcessor.java
@@ -35,7 +35,12 @@ public class GrChangeSignatureUsageProcessor implements ChangeSignatureUsageProc
   }
 
   public MultiMap<PsiElement, String> findConflicts(ChangeInfo info, Ref<UsageInfo[]> refUsages) {
-    return null;  //To change body of implemented methods use File | Settings | File Templates.
+    if (info instanceof JavaChangeInfo) {
+      return new GrChangeSignatureConflictSearcher((JavaChangeInfo)info).findConflicts(refUsages);
+    }
+    else {
+      return new MultiMap<PsiElement, String>();
+    }
   }
 
   public boolean processUsage(ChangeInfo changeInfo, UsageInfo usageInfo, boolean beforeMethodChange, UsageInfo[] usages) {