extract delegate: ensure class fqns are not lost (IDEA-163265)

java/java-impl/src/com/intellij/refactoring/extractclass/ExtractedClassBuilder.java

@@ -18,7 +18,6 @@ package com.intellij.refactoring.extractclass;
 import com.intellij.codeInsight.generation.GenerateMembersUtil;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.project.Project;
-import com.intellij.openapi.util.Condition;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.*;
 import com.intellij.psi.codeStyle.JavaCodeStyleManager;
@@ -26,7 +25,6 @@ import com.intellij.psi.codeStyle.VariableKind;
 import com.intellij.psi.tree.IElementType;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.refactoring.psi.MethodInheritanceUtils;
-import com.intellij.util.Function;
 import com.intellij.util.IncorrectOperationException;
 import org.jetbrains.annotations.NonNls;
 
@@ -438,6 +436,12 @@ class ExtractedClassBuilder {
             }
           }
         }
+        else if (referent instanceof PsiClass) {
+          String qualifiedName = ((PsiClass)referent).getQualifiedName();
+          if (qualifiedName != null) {
+            out.append(qualifiedName);
+          }
+        }
         else {
           visitElement(expression);
         }

java/java-tests/testData/refactoring/extractClass/ensurePreservedQualifier/after/Extracted.java

@@ -0,0 +1,11 @@
+import java.util.Collections;
+import java.util.List;
+
+public class Extracted {
+    public Extracted() {
+    }
+
+    List<Test> foo() {
+        return Collections.emptyList();
+    }
+}

java/java-tests/testData/refactoring/extractClass/ensurePreservedQualifier/after/Test.java

@@ -0,0 +1,2 @@
+public class Test {
+}

java/java-tests/testData/refactoring/extractClass/ensurePreservedQualifier/before/Test.java

@@ -0,0 +1,9 @@
+
+import java.util.Collections;
+import java.util.List;
+
+public class Test {
+  List<Test> foo() {
+    return Collections.emptyList();
+  }
+}

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2014 JetBrains s.r.o.
+ * Copyright 2000-2016 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.
@@ -160,6 +160,10 @@ public class ExtractClassTest extends MultiFileTestCase{
     doTestInnerClass();
   }
 
+  public void testEnsurePreservedQualifier() throws Exception {
+    doTestMethod();
+  }
+
   private void doTestFieldAndMethod(final String methodName) throws Exception {
     doTest((rootDir, rootAfter) -> {
       PsiClass aClass = myJavaFacade.findClass("Test", GlobalSearchScope.projectScope(myProject));