inline to anonymous: convert to lambda when applicable (IDEA-173821)

java/java-impl/src/com/intellij/refactoring/inline/InlineToAnonymousConstructorProcessor.java

@@ -16,6 +16,7 @@
 package com.intellij.refactoring.inline;
 
 import com.intellij.codeInsight.ChangeContextUtil;
+import com.intellij.codeInspection.AnonymousCanBeLambdaInspection;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Key;
@@ -35,10 +36,7 @@ import com.intellij.util.ProcessingContext;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import static com.intellij.patterns.PlatformPatterns.psiElement;
 import static com.intellij.patterns.PsiJavaPatterns.psiExpressionStatement;
@@ -159,7 +157,15 @@ class InlineToAnonymousConstructorProcessor {
     }
     PsiNewExpression superNewExpression = (PsiNewExpression) myNewExpression.replace(superNewExpressionTemplate);
     superNewExpression = (PsiNewExpression)ChangeContextUtil.decodeContextInfo(superNewExpression, superNewExpression.getAnonymousClass(), null);
-    JavaCodeStyleManager.getInstance(superNewExpression.getProject()).shortenClassReferences(superNewExpression);
+    PsiAnonymousClass newExpressionAnonymousClass = superNewExpression.getAnonymousClass();
+    if (newExpressionAnonymousClass != null && 
+        AnonymousCanBeLambdaInspection.canBeConvertedToLambda(newExpressionAnonymousClass, false, Collections.emptySet())) {
+      PsiExpression lambda = AnonymousCanBeLambdaInspection.replaceAnonymousWithLambda(superNewExpression, newExpressionAnonymousClass.getBaseClassType());
+      JavaCodeStyleManager.getInstance(newExpressionAnonymousClass.getProject()).shortenClassReferences(superNewExpression.replace(lambda));
+    }
+    else {
+      JavaCodeStyleManager.getInstance(superNewExpression.getProject()).shortenClassReferences(superNewExpression);
+    }
   }
 
   private void insertInitializerBefore(final PsiClassInitializer initializerBlock, final PsiClass anonymousClass, final PsiElement token)

java/java-tests/testData/refactoring/inlineToAnonymousClass/ConvertToLambdaJava8.java

@@ -0,0 +1,14 @@
+import java.util.*;
+
+class Main {
+    public class <caret>MyComparator implements Comparator<String> {
+        @Override
+        public int compare(String s1, String s2) {
+            return 0;
+        }
+    }
+    
+    void sort(List<String> scores) {
+        scores.sort(new MyComparator());
+    }
+}

java/java-tests/testData/refactoring/inlineToAnonymousClass/ConvertToLambdaJava8.java.after

@@ -0,0 +1,8 @@
+import java.util.*;
+
+class Main {
+
+    void sort(List<String> scores) {
+        scores.sort((s1, s2) -> 0);
+    }
+}

java/java-tests/testSrc/com/intellij/java/refactoring/inline/InlineToAnonymousClassTest.java

@@ -54,6 +54,10 @@ public class InlineToAnonymousClassTest extends LightRefactoringTestCase {
     doTest(false, false);
   }
 
+  public void testConvertToLambdaJava8() throws Exception {
+    doTest(false, false);
+  }
+
   public void testClassInitializer() throws Exception {
     doTest(false, false);
   }
@@ -499,6 +503,9 @@ public class InlineToAnonymousClassTest extends LightRefactoringTestCase {
 
   @Override
   protected LanguageLevel getLanguageLevel() {
+    if (getTestName(false).endsWith("Java8")) {
+      return LanguageLevel.JDK_1_8;
+    }
     return LanguageLevel.JDK_1_7;
   }
 }