diff --git a/java/java-tests/testSrc/com/intellij/psi/SrcRepositoryUseTest.java b/java/java-tests/testSrc/com/intellij/psi/SrcRepositoryUseTest.java
index 5e4d78facda4..ca3c67108da7 100644
--- a/java/java-tests/testSrc/com/intellij/psi/SrcRepositoryUseTest.java
+++ b/java/java-tests/testSrc/com/intellij/psi/SrcRepositoryUseTest.java
@@ -29,6 +29,7 @@ import com.intellij.testFramework.PsiTestUtil;
 import java.io.File;
 import java.io.IOException;
 
+@SuppressWarnings("ConstantConditions")
 @PlatformTestCase.WrapInCommand
 public class SrcRepositoryUseTest extends PsiTestCase{
   private static final Logger LOG = Logger.getInstance("#com.intellij.psi.SrcRepositoryUseTest");
@@ -501,8 +502,9 @@ public class SrcRepositoryUseTest extends PsiTestCase{
     setupLoadingFilter();
 
     PsiClass aClass = myJavaFacade.findClass("pack.MyClass2", GlobalSearchScope.allScope(myProject));
-
-    PsiParameterList list = aClass.getMethods()[0].getParameterList();
+    assertNotNull(aClass);
+    PsiMethod[] methods = aClass.getMethods();
+    PsiParameterList list = methods[0].getParameterList();
 
     PsiParameter[] parms = list.getParameters();
     assertEquals(5, parms.length);
diff --git a/platform/core-impl/src/com/intellij/psi/impl/PsiManagerImpl.java b/platform/core-impl/src/com/intellij/psi/impl/PsiManagerImpl.java
index d473589db14b..f3a3f3655de8 100644
--- a/platform/core-impl/src/com/intellij/psi/impl/PsiManagerImpl.java
+++ b/platform/core-impl/src/com/intellij/psi/impl/PsiManagerImpl.java
@@ -142,7 +142,8 @@ public class PsiManagerImpl extends PsiManagerEx {
     return false;
   }
 
-  public void setAssertOnFileLoadingFilter(VirtualFileFilter filter) {
+  @TestOnly
+  public void setAssertOnFileLoadingFilter(@NotNull VirtualFileFilter filter) {
     // Find something to ensure there's no changed files waiting to be processed in repository indices.
     myAssertOnFileLoadingFilter = filter;
   }
diff --git a/platform/testFramework/src/com/intellij/testFramework/FileTreeAccessFilter.java b/platform/testFramework/src/com/intellij/testFramework/FileTreeAccessFilter.java
index 678dbefbbbcb..06155a9004ef 100755
--- a/platform/testFramework/src/com/intellij/testFramework/FileTreeAccessFilter.java
+++ b/platform/testFramework/src/com/intellij/testFramework/FileTreeAccessFilter.java
@@ -17,11 +17,11 @@ package com.intellij.testFramework;
 
 import com.intellij.injected.editor.VirtualFileWindow;
 import com.intellij.openapi.fileTypes.FileType;
-import com.intellij.openapi.fileTypes.FileTypeManager;
 import com.intellij.openapi.fileTypes.StdFileTypes;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.vfs.VirtualFileFilter;
 import gnu.trove.THashSet;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
 import java.util.Set;
@@ -43,7 +43,7 @@ public class FileTreeAccessFilter implements VirtualFileFilter {
     return (fileType == StdFileTypes.JAVA || fileType == StdFileTypes.CLASS) && !file.getName().equals("package-info.java");
   }
 
-  public void allowTreeAccessForFile(VirtualFile file) {
+  public void allowTreeAccessForFile(@NotNull VirtualFile file) {
     myAddedClasses.add(file);
   }
 
diff --git a/platform/testFramework/src/com/intellij/testFramework/fixtures/CodeInsightTestFixture.java b/platform/testFramework/src/com/intellij/testFramework/fixtures/CodeInsightTestFixture.java
index 6be249c5717e..0571b0f8ee77 100644
--- a/platform/testFramework/src/com/intellij/testFramework/fixtures/CodeInsightTestFixture.java
+++ b/platform/testFramework/src/com/intellij/testFramework/fixtures/CodeInsightTestFixture.java
@@ -358,7 +358,7 @@ public interface CodeInsightTestFixture extends IdeaProjectTestFixture {
 
   void renameElement(PsiElement element, String newName);
 
-  void allowTreeAccessForFile(VirtualFile file);
+  void allowTreeAccessForFile(@NotNull VirtualFile file);
 
   void allowTreeAccessForAllFiles();
 
diff --git a/platform/testFramework/src/com/intellij/testFramework/fixtures/impl/CodeInsightTestFixtureImpl.java b/platform/testFramework/src/com/intellij/testFramework/fixtures/impl/CodeInsightTestFixtureImpl.java
index dfe811c516db..7e8b2360c90c 100644
--- a/platform/testFramework/src/com/intellij/testFramework/fixtures/impl/CodeInsightTestFixtureImpl.java
+++ b/platform/testFramework/src/com/intellij/testFramework/fixtures/impl/CodeInsightTestFixtureImpl.java
@@ -1487,7 +1487,7 @@ public class CodeInsightTestFixtureImpl extends BaseFixture implements CodeInsig
   }
 
   @Override
-  public void allowTreeAccessForFile(final VirtualFile file) {
+  public void allowTreeAccessForFile(@NotNull final VirtualFile file) {
     myJavaFilesFilter.allowTreeAccessForFile(file);
   }