diff --git a/java/java-psi-api/src/com/intellij/psi/PsiArrayType.java b/java/java-psi-api/src/com/intellij/psi/PsiArrayType.java
index 6c950ad5e293..50777e6d878b 100644
--- a/java/java-psi-api/src/com/intellij/psi/PsiArrayType.java
+++ b/java/java-psi-api/src/com/intellij/psi/PsiArrayType.java
@@ -1,22 +1,9 @@
-/*
- * Copyright 2000-2017 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.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.psi;
 
 import com.intellij.lang.jvm.types.JvmArrayType;
 import com.intellij.psi.search.GlobalSearchScope;
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 
 /**
@@ -114,6 +101,7 @@ public class PsiArrayType extends PsiType.Stub implements JvmArrayType {
    */
   @NotNull
   @Override
+  @Contract(pure = true)
   public PsiType getComponentType() {
     return myComponentType;
   }
diff --git a/java/java-psi-api/src/com/intellij/psi/PsiEllipsisType.java b/java/java-psi-api/src/com/intellij/psi/PsiEllipsisType.java
index 6b6d50a0ee8a..937feef79a35 100644
--- a/java/java-psi-api/src/com/intellij/psi/PsiEllipsisType.java
+++ b/java/java-psi-api/src/com/intellij/psi/PsiEllipsisType.java
@@ -1,20 +1,7 @@
-/*
- * 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.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.psi;
 
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 
 /**
@@ -69,6 +56,7 @@ public class PsiEllipsisType extends PsiArrayType {
    *
    * @return the array type instance.
    */
+  @Contract(pure = true)
   public PsiType toArrayType() {
     return new PsiArrayType(getComponentType(), getAnnotationProvider());
   }
diff --git a/java/java-psi-api/src/com/intellij/psi/PsiExpression.java b/java/java-psi-api/src/com/intellij/psi/PsiExpression.java
index 80dcd4d06994..cf5d17856c60 100644
--- a/java/java-psi-api/src/com/intellij/psi/PsiExpression.java
+++ b/java/java-psi-api/src/com/intellij/psi/PsiExpression.java
@@ -1,24 +1,10 @@
-/*
- * Copyright 2000-2015 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.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.psi;
 
 import com.intellij.util.ArrayFactory;
 import com.intellij.util.Function;
 import com.intellij.util.NullableFunction;
-import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.Nullable;
 
 /**
@@ -40,5 +26,6 @@ public interface PsiExpression extends PsiAnnotationMemberValue {
    * @return the expression type, or null if the type is not known.
    */
   @Nullable
+  @Contract(pure = true)
   PsiType getType();
 }
diff --git a/java/java-psi-api/src/com/intellij/psi/PsiTypeElement.java b/java/java-psi-api/src/com/intellij/psi/PsiTypeElement.java
index 1be650b01200..3bbbac1d0d25 100644
--- a/java/java-psi-api/src/com/intellij/psi/PsiTypeElement.java
+++ b/java/java-psi-api/src/com/intellij/psi/PsiTypeElement.java
@@ -1,21 +1,8 @@
-/*
- * 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.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.psi;
 
 import com.intellij.util.ArrayFactory;
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -44,6 +31,7 @@ public interface PsiTypeElement extends PsiElement, PsiAnnotationOwner {
    * @see PsiVariable#getType()
    */
   @NotNull
+  @Contract(pure = true)
   PsiType getType();
 
   /**
@@ -65,6 +53,7 @@ public interface PsiTypeElement extends PsiElement, PsiAnnotationOwner {
    * 
    * Applicable to local variables with initializers, foreach parameters, try-with-resources variables 
    */
+  @Contract(pure = true)
   default boolean isInferredType() {
     return false;
   }