optional model

Reviewed By: jvillard

Differential Revision: D3400635

fbshipit-source-id: 2078050

infer/models/java/src/com/google/common/base/Optional.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2013 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.google.common.base;
+
+import javax.annotation.Nullable;
+
+public abstract class Optional<T>  {
+
+  @Nullable
+  public abstract T orNull();
+
+}

infer/tests/build_systems/expected_outputs/ant_report.json

@@ -649,6 +649,11 @@
     "file": "codetoanalyze/java/infer/ResourceLeaks.java",
     "procedure": "void ResourceLeaks.openHttpsURLConnectionNotDisconnected()"
   },
+  {
+    "bug_type": "NULL_DEREFERENCE",
+    "file": "codetoanalyze/java/infer/NullPointerExceptions.java",
+    "procedure": "void NullPointerExceptions.optionalNPE(Optional)"
+  },
   {
     "bug_type": "NULL_DEREFERENCE",
     "file": "codetoanalyze/java/infer/NullPointerExceptions.java",

infer/tests/build_systems/expected_outputs/buck_report.json

@@ -649,6 +649,11 @@
     "file": "infer/tests/codetoanalyze/java/infer/ResourceLeaks.java",
     "procedure": "void ResourceLeaks.openHttpsURLConnectionNotDisconnected()"
   },
+  {
+    "bug_type": "NULL_DEREFERENCE",
+    "file": "infer/tests/codetoanalyze/java/infer/NullPointerExceptions.java",
+    "procedure": "void NullPointerExceptions.optionalNPE(Optional)"
+  },
   {
     "bug_type": "NULL_DEREFERENCE",
     "file": "infer/tests/codetoanalyze/java/infer/NullPointerExceptions.java",

infer/tests/codetoanalyze/java/infer/NullPointerExceptions.java

@@ -15,6 +15,7 @@ import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.text.TextUtils;
 
+import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 
@@ -558,4 +559,9 @@ public class NullPointerExceptions {
     s.toString(); // Expect NPE here
   }
 
+  void optionalNPE(Optional<Object> o) {
+    o.orNull().toString();
+  }
+
+
 }

infer/tests/endtoend/java/infer/NullPointerExceptionTest.java

@@ -74,6 +74,7 @@ public class NullPointerExceptionTest {
         "dereferenceAfterLoopOnList",
         "dereferenceAfterUnlock1",
         "dereferenceAfterUnlock2",
+        "optionalNPE",
     };
     assertThat(
         "Results should contain " + NULL_DEREFERENCE,