[java] better inner class detection (IDEA-132606)

java/java-psi-impl/src/com/intellij/psi/ClassFileViewProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2015 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.
@@ -17,19 +17,29 @@ package com.intellij.psi;
 
 import com.intellij.ide.highlighter.JavaClassFileType;
 import com.intellij.openapi.components.ServiceManager;
+import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.roots.FileIndexFacade;
+import com.intellij.openapi.util.Key;
+import com.intellij.openapi.util.Ref;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.impl.PsiManagerImpl;
 import com.intellij.psi.impl.compiled.ClsFileImpl;
 import com.intellij.psi.impl.file.PsiBinaryFileImpl;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.org.objectweb.asm.ClassReader;
+import org.jetbrains.org.objectweb.asm.ClassVisitor;
+import org.jetbrains.org.objectweb.asm.Opcodes;
+
+import java.io.IOException;
 
 /**
  * @author max
  */
 public class ClassFileViewProvider extends SingleRootFileViewProvider {
+  private static final Key<Boolean> IS_INNER_CLASS = Key.create("java.is.inner.class.key");
+
   public ClassFileViewProvider(@NotNull PsiManager manager, @NotNull VirtualFile file) {
     super(manager, file);
   }
@@ -45,7 +55,7 @@ public class ClassFileViewProvider extends SingleRootFileViewProvider {
       return new PsiBinaryFileImpl((PsiManagerImpl)getManager(), this);
     }
 
-    // skip inners & anonymous
+    // skip inner & anonymous
     if (isInnerClass(file)) return null;
 
     return new ClsFileImpl(this);
@@ -53,16 +63,45 @@ public class ClassFileViewProvider extends SingleRootFileViewProvider {
 
   public static boolean isInnerClass(@NotNull VirtualFile file) {
     String name = file.getNameWithoutExtension();
-    int index = name.lastIndexOf('$', name.length());
+    int index = name.lastIndexOf('$');
     if (index > 0 && index < name.length() - 1) {
-      String supposedParentName = name.substring(0, index) + ".class";
-      if (file.getParent().findChild(supposedParentName) != null) {
-        return true;
+      String parentName = name.substring(0, index), childName = name.substring(index + 1);
+      if (file.getParent().findChild(parentName + ".class") != null) {
+        return isInnerClass(file, parentName, childName);
       }
     }
     return false;
   }
 
+  private static boolean isInnerClass(VirtualFile file, final String parentName, final String childName) {
+    Boolean isInner = IS_INNER_CLASS.get(file);
+    if (isInner != null) return isInner;
+
+    final Ref<Boolean> ref = Ref.create(Boolean.FALSE);
+    try {
+      new ClassReader(file.contentsToByteArray(false)).accept(new ClassVisitor(Opcodes.ASM5) {
+        @Override
+        public void visitOuterClass(String owner, String name, String desc) {
+          ref.set(Boolean.TRUE);
+        }
+
+        @Override
+        public void visitInnerClass(String name, String outer, String inner, int access) {
+          if (inner == null || childName.equals(inner) && outer != null && parentName.equals(outer.substring(outer.lastIndexOf('/') + 1))) {
+            ref.set(Boolean.TRUE);
+          }
+        }
+      }, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES);
+    }
+    catch (IOException e) {
+      Logger.getInstance(ClassFileViewProvider.class).info(e);
+    }
+
+    isInner = ref.get();
+    IS_INNER_CLASS.set(file, isInner);
+    return isInner;
+  }
+
   @NotNull
   @Override
   public SingleRootFileViewProvider createCopy(@NotNull VirtualFile copy) {

java/java-psi-impl/src/com/intellij/psi/impl/compiled/ClassFileStubBuilder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2015 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.
@@ -51,30 +51,32 @@ public class ClassFileStubBuilder implements BinaryFileStubBuilder {
     byte[] content = fileContent.getContent();
 
     try {
-      file.setPreloadedContentHint(content);
-      ClassFileDecompilers.Decompiler decompiler = ClassFileDecompilers.find(file);
-      if (decompiler instanceof Full) {
-        return ((Full)decompiler).getStubBuilder().buildFileStub(fileContent);
+      try {
+        file.setPreloadedContentHint(content);
+        ClassFileDecompilers.Decompiler decompiler = ClassFileDecompilers.find(file);
+        if (decompiler instanceof Full) {
+          return ((Full)decompiler).getStubBuilder().buildFileStub(fileContent);
+        }
+      }
+      catch (ClsFormatException e) {
+        LOG.debug(e);
+      }
+
+      try {
+        PsiFileStub<?> stub = ClsFileImpl.buildFileStub(file, content);
+        if (stub == null && fileContent.getFileName().indexOf('$') >= 0) {
+          LOG.info("No stub built for file " + fileContent);
+        }
+        return stub;
+      }
+      catch (ClsFormatException e) {
+        LOG.debug(e);
       }
-    }
-    catch (ClsFormatException e) {
-      LOG.debug(e);
     }
     finally {
       file.setPreloadedContentHint(null);
     }
 
-    try {
-      PsiFileStub<?> stub = ClsFileImpl.buildFileStub(file, content);
-      if (stub == null && !fileContent.getFileName().contains("$")) {
-        LOG.info("No stub built for file " + fileContent);
-      }
-      return stub;
-    }
-    catch (ClsFormatException e) {
-      LOG.debug(e);
-    }
-
     return null;
   }
 
@@ -99,4 +101,4 @@ public class ClassFileStubBuilder implements BinaryFileStubBuilder {
 
     return version;
   }
-}
+}

java/java-tests/testData/psi/cls/mirror/src/pkg/KindaInner$Class.java

@@ -0,0 +1,3 @@
+package pkg;
+
+class KindaInner$Class { }

java/java-tests/testData/psi/cls/mirror/src/pkg/KindaInner.java

@@ -0,0 +1,3 @@
+package pkg;
+
+class KindaInner { }

java/java-tests/testSrc/com/intellij/psi/ClsMirrorBuildingTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2015 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.
@@ -161,6 +161,14 @@ public class ClsMirrorBuildingTest extends LightIdeaTestCase {
     }
   }
 
+  public void testInnerClassDetection() {
+    assertTrue(isInner("Nested$Inner1"));
+    assertTrue(isInner("Nested$Inner1$Inner2"));
+    assertTrue(isInner("NormalClass$1"));
+    assertTrue(isInner("LocalClass$1MyRunnable"));
+    assertFalse(isInner("KindaInner$Class"));
+  }
+
   private static String getTestDataDir() {
     return JavaTestUtil.getJavaTestDataPath() + "/psi/cls/mirror/";
   }
@@ -188,4 +196,10 @@ public class ClsMirrorBuildingTest extends LightIdeaTestCase {
 
     assertEquals(expected, ClsFileImpl.decompile(file).toString());
   }
-}
+
+  private static boolean isInner(String name) {
+    VirtualFile file = StandardFileSystems.local().findFileByPath(getTestDataDir() + "pkg/" + name + ".class");
+    assertNotNull(file);
+    return ClassFileViewProvider.isInnerClass(file);
+  }
+}