[java] don't warn on unclosed subclasses of non-resource types

Summary:
We already knew not to warn when non-resource `Closeable`'s like `ByteArrayOutputStream` weren't closed, but we still warned on their subtypes.
This diff fixes that problem by checking subclasses in the frontend.
This also removes the need for Java source code models of non-resource types, so I removed them.

Reviewed By: jeremydubreil

Differential Revision: D6843413

fbshipit-source-id: 60fe7fb

infer/models/java/src/java/io/ByteArrayInputStream.java

@@ -1,20 +0,0 @@
-/*
- * Copyright (c) 2015 - 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 java.io;
-
-public class ByteArrayInputStream extends InputStream implements Closeable {
-
-  public ByteArrayInputStream(byte[] buf) {}
-
-  public ByteArrayInputStream(byte[] buf, int offset, int length) {}
-
-  public void close() {}
-
-}

infer/models/java/src/java/io/ByteArrayOutputStream.java

@@ -1,26 +0,0 @@
-/*
- * Copyright (c) 2015 - 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 java.io;
-
-public class ByteArrayOutputStream extends OutputStream implements Closeable {
-
-  public ByteArrayOutputStream() {}
-
-  public ByteArrayOutputStream(int size) {}
-
-  @Override
-  public void write(int b) {}
-
-  @Override
-  public void write(byte[] b, int off, int len) {}
-
-  public void close() {}
-
-}

infer/models/java/src/java/io/StringReader.java

@@ -1,18 +0,0 @@
-/*
- * Copyright (c) 2015 - 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 java.io;
-
-public class StringReader implements Closeable {
-
-  public StringReader(String s) {}
-
-  public void close() {}
-
-}

infer/models/java/src/java/io/StringWriter.java

@@ -1,19 +0,0 @@
-/*
- * Copyright (c) 2015 - 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 java.io;
-
-public class StringWriter implements Closeable{
-
-  public StringWriter() {}
-  public StringWriter(int initialSize) {}
-
-  public void close() {}
-
-}

infer/src/java/jTrans.ml

@@ -656,6 +656,18 @@ let method_invocation (context: JContext.t) loc pc var_opt cn ms sil_obj_opt exp
     | _ ->
         false
   in
+  (* return true for classes that are a subclass of Closeable, but don't actually represent a
+     resource *)
+  let is_non_resource_closeable typename _ =
+    match Typ.Name.name typename with
+    | "java.io.ByteArrayInputStream"
+    | "java.io.ByteArrayOutputStream"
+    | "java.io.StringReader"
+    | "java.io.StringWriter" ->
+        true
+    | _ ->
+        false
+  in
   let instrs =
     match call_args with
     (* modeling a class bypasses the treatment of Closeable *)
@@ -665,7 +677,8 @@ let method_invocation (context: JContext.t) loc pc var_opt cn ms sil_obj_opt exp
     | ((_, {Typ.desc= Typ.Tptr ({desc= Tstruct typename}, _)}) as exp) :: _
     (* add a file attribute when calling the constructor of a subtype of Closeable *)
       when Typ.Procname.is_constructor callee_procname
-           && AndroidFramework.is_autocloseable tenv typename ->
+           && AndroidFramework.is_autocloseable tenv typename
+           && not (PatternMatch.supertype_exists tenv is_non_resource_closeable typename) ->
         let set_file_attr =
           let set_builtin = Exp.Const (Const.Cfun BuiltinDecl.__set_file_attribute) in
           Sil.Call (None, set_builtin, [exp], loc, CallFlags.default)

infer/tests/codetoanalyze/java/infer/CloseableAsResourceExample.java

@@ -66,6 +66,16 @@ class ResourceWithException implements Closeable {
   }
 }
 
+class ByteArrayOutputStreamWrapper extends ByteArrayOutputStream {
+}
+
+class ByteArrayInputStreamWrapper extends ByteArrayInputStream {
+
+  public ByteArrayInputStreamWrapper(byte[] arr) {
+    super(arr);
+  }
+}
+
 public class CloseableAsResourceExample {
 
   native static boolean star();
@@ -115,6 +125,11 @@ public class CloseableAsResourceExample {
     ByteArrayOutputStream stream = new ByteArrayOutputStream(42);
   }
 
+  void noCloseByteArrayWrappersOk(byte[] array) {
+    ByteArrayOutputStreamWrapper stream1 = new ByteArrayOutputStreamWrapper();
+    ByteArrayInputStreamWrapper stream2 = new ByteArrayInputStreamWrapper(array);
+  }
+
   void noNeedToCloseByteArrayInputStream(byte[] array) {
     ByteArrayInputStream stream = new ByteArrayInputStream(array);
   }