safe delete: fixed delete from the top of the hierarchy

java/java-impl/src/com/intellij/refactoring/safeDelete/JavaSafeDeleteProcessor.java

@@ -111,7 +111,11 @@ public class JavaSafeDeleteProcessor implements SafeDeleteProcessorDelegate {
       final Set<PsiParameter> parametersToDelete = new HashSet<PsiParameter>();
       parametersToDelete.add((PsiParameter) element);
       final int parameterIndex = method.getParameterList().getParameterIndex((PsiParameter) element);
-      for (PsiMethod superMethod : method.findDeepestSuperMethods()) {
+      final List<PsiMethod> superMethods = new ArrayList<PsiMethod>(Arrays.asList(method.findDeepestSuperMethods()));
+      if (superMethods.isEmpty()) {
+        superMethods.add(method);
+      }
+      for (PsiMethod superMethod : superMethods) {
         parametersToDelete.add(superMethod.getParameterList().getParameters()[parameterIndex]);
         OverridingMethodsSearch.search(superMethod).forEach(new Processor<PsiMethod>() {
           public boolean process(PsiMethod overrider) {

java/java-tests/testData/refactoring/safeDelete/topParameterInHierarchy/after/C1.java

@@ -0,0 +1,5 @@
+public class C1 implements I {
+  public void f(int a1) {
+
+  }
+}

java/java-tests/testData/refactoring/safeDelete/topParameterInHierarchy/after/I.java

@@ -0,0 +1,3 @@
+public interface I {
+  void f(int a1);
+}

java/java-tests/testData/refactoring/safeDelete/topParameterInHierarchy/after/Super.java

@@ -0,0 +1,5 @@
+public class C2 extends C1 {
+  public void f(int a1) {
+    super.f(a1 );
+  }
+}

java/java-tests/testData/refactoring/safeDelete/topParameterInHierarchy/before/C1.java

@@ -0,0 +1,5 @@
+public class C1 implements I {
+  public void f(int a1, int a2) {
+
+  }
+}

java/java-tests/testData/refactoring/safeDelete/topParameterInHierarchy/before/I.java

@@ -0,0 +1,3 @@
+public interface I {
+  void f(int a1, int a<caret>2);
+}

java/java-tests/testData/refactoring/safeDelete/topParameterInHierarchy/before/Super.java

@@ -0,0 +1,5 @@
+public class C2 extends C1 {
+  public void f(int a1, int a2) {
+    super.f(a1, a2);
+  }
+}

java/java-tests/testSrc/com/intellij/refactoring/SafeDeleteTest.java

@@ -62,6 +62,11 @@ public class SafeDeleteTest extends MultiFileTestCase {
     doTest("C2");
   }
 
+  public void testTopParameterInHierarchy() throws Exception {
+    myDoCompare = false;
+    doTest("I");
+  }
+
   public void testExtendsList() throws Exception {
     myDoCompare = false;
     doTest("B");