mojo: Validate fixed size array for the mojo java bindings.

mojo/public/tools/bindings/generators/mojom_java_generator.py

Index: mojo/public/tools/bindings/generators/mojom_java_generator.py
diff --git a/mojo/public/tools/bindings/generators/mojom_java_generator.py b/mojo/public/tools/bindings/generators/mojom_java_generator.py
index 1827ed90c773953d207858ba10473679ca822bde..7cbfe543bcb905200edac992fc2b8d112e427111 100644
--- a/mojo/public/tools/bindings/generators/mojom_java_generator.py
+++ b/mojo/public/tools/bindings/generators/mojom_java_generator.py
@@ -152,6 +152,12 @@ def DecodeMethod(context, kind, offset, bit):
   params = [ str(offset) ]
   if (kind == mojom.BOOL):
     params.append(str(bit))
+  if mojom.IsAnyArrayKind(kind):
+    if mojom.IsFixedArrayKind(kind):
+      params.append(str(kind.length))
+    else:
+      params.append(
+        "org.chromium.mojo.bindings.BindingsHelper.UNSPECIFIED_ARRAY_LENGTH");
   if mojom.IsInterfaceKind(kind):
     params.append('%s.MANAGER' % GetJavaType(context, kind))
   if mojom.IsAnyArrayKind(kind) and mojom.IsInterfaceKind(kind.kind):
@@ -163,6 +169,12 @@ def EncodeMethod(context, kind, variable, offset, bit):
   params = [ variable, str(offset) ]
   if (kind == mojom.BOOL):
     params.append(str(bit))
+  if mojom.IsAnyArrayKind(kind):
+    if mojom.IsFixedArrayKind(kind):
+      params.append(str(kind.length))
+    else:
+      params.append(
+        "org.chromium.mojo.bindings.BindingsHelper.UNSPECIFIED_ARRAY_LENGTH");

[yzshen1, 2014/08/29 16:32:24]

One nit: Other bindings use 0 as "unspecified length". I understand that they
don't affect each other, but it may worth considering to unify them:
https://code.google.com/p/chromium/codesearch#chromium/src/mojo/public/tools/...

[qsr, 2014/09/01 09:07:00]

 Not sure to understand exactly what to do here. The -1, 0 debate aside, I'm
using a constant here to make the code more readable. Do you want use to do this
in all bindings?

 For the -1, 0, I will push like this, and change to 0 if the discussion ends up
deciding we never want fixed size arrays of size 0.

   if mojom.IsInterfaceKind(kind):
     params.append('%s.MANAGER' % GetJavaType(context, kind))
   if mojom.IsAnyArrayKind(kind) and mojom.IsInterfaceKind(kind.kind):
@@ -323,6 +335,7 @@ class Generator(generator.Generator):
     "encode_method": EncodeMethod,
     "has_method_with_response": HasMethodWithResponse,
     "has_method_without_response": HasMethodWithoutResponse,
+    "is_fixed_array_kind": mojom.IsFixedArrayKind,
     "is_handle": mojom.IsNonInterfaceHandleKind,
     "is_pointer_array_kind": IsPointerArrayKind,
     "is_struct_kind": mojom.IsStructKind,