Generate enum validation for Mojo Java bindings

BUG=581392
TESTED='build/android/test_runner.py instrumentation --test-apk MojoTest'

Review-Url: https://codereview.chromium.org/1968373002
Cr-Commit-Position: refs/heads/master@{#394036}

mojo/android/javatests/src/org/chromium/mojo/bindings/ValidationTest.java

@@ -59,11 +59,6 @@ public boolean accept(File pathname) {
             if (pathname.getName().startsWith("conformance_mthd13_good_2")) {
                 return false;
             }
-            // TODO(yzshen): skip enum validation tests because the feature is
-            // not supported in Java yet. crbug.com/581392
-            if (pathname.getName().indexOf("enum") != -1) {
-                return false;
-            }
             return pathname.isFile() && pathname.getName().startsWith(mPrefix)
                     && pathname.getName().endsWith(".data");
         }

mojo/public/interfaces/bindings/tests/data/validation/conformance_mthd16_uknown_non_extensible_enum_map_entry.data

@@ -0,0 +1,34 @@
+[dist4]message_header  // num_bytes
+[u4]0                  // version
+[u4]0                  // interface ID
+[u4]16                 // name
+[u4]0                  // flags
+[u4]0                  // padding
+[anchr]message_header
+
+[dist4]method16_params  // num_bytes
+[u4]0                   // version
+[dist8]map_data_ptr     // param0
+[anchr]method16_params
+
+[anchr]map_data_ptr
+[dist4]map_data_struct_header  // num_bytes
+[u4]0                          // version
+[dist8]key_array_ptr
+[dist8]value_array_ptr
+[anchr]map_data_struct_header
+
+[anchr]key_array_ptr
+[dist4]key_array_member     // num_bytes
+[u4]2                       // num_elements
+[u4]0x5678                  // Unknown value is not allowed for non-extensible
+                            // enum.
+[u4]1
+[anchr]key_array_member
+
+[anchr]value_array_ptr
+[dist4]value_array_member   // num_bytes
+[u4]2                       // num_elements
+[u4]0x5678                  // Unknown value is allowed for extensible enum.
+[u4]1
+[anchr]value_array_member

mojo/public/interfaces/bindings/tests/data/validation/conformance_mthd16_uknown_non_extensible_enum_map_entry.expected

@@ -0,0 +1 @@
+VALIDATION_ERROR_UNKNOWN_ENUM_VALUE

mojo/public/interfaces/bindings/tests/validation_test_interfaces.mojom

@@ -82,6 +82,7 @@ interface ConformanceTestInterface {
   Method13(InterfaceA? param0, uint32 param1, InterfaceA? param2);
   Method14(EnumA param0, EnumB param1);
   Method15(array<EnumA>? param0, array<EnumB>? param1);
+  Method16(map<EnumA, EnumB>? param0);
 };
 
 struct BasicStruct {

mojo/public/tools/bindings/generators/java_templates/data_types_definition.tmpl

@@ -122,6 +122,19 @@ if (decoder{{level+1}} == null) {
 {{variable}} = {{kind|java_type}}.decode(decoder{{level}}, {{offset}});
 {% else %}
 {{variable}} = decoder{{level}}.{{kind|decode_method(offset, bit)}};
+{%   if kind|is_array_kind and kind.kind|is_enum_kind %}
+{%     if kind|is_nullable_kind %}
+if ({{variable}} != null) {
+{%     else %}
+{
+{%     endif %}
+    for (int i{{level}} = 0; i{{level}} < {{variable}}.length; ++i{{level}}) {
+        {{kind.kind|java_class_for_enum}}.validate({{variable}}[i{{level}}]);
+    }
+}
+{%   elif kind|is_enum_kind %}
+    {{kind|java_class_for_enum}}.validate({{variable}});
+{%   endif %}
 {% endif %}
 {% endmacro %}
 

mojo/public/tools/bindings/generators/java_templates/enum_definition.tmpl

@@ -15,6 +15,25 @@ public {{ 'static ' if not top_level }}final class {{enum|name}} {
     public static final int {{field|name}} = {{enum_value(enum, field, loop.index0)}};
 {% endfor %}
 
+    private static final boolean IS_EXTENSIBLE = {% if enum.extensible %}true{% else %}false{% endif %};
+
+    public static boolean isKnownValue(int value) {
+        switch (value) {
+{%- for enum_field in enum.fields|groupby('numeric_value') %}
+            case {{enum_field[0]}}:
+{%- endfor %}
+                return true;
+        }
+        return false;
+    }
+
+    public static void validate(int value) {
+        if (IS_EXTENSIBLE || isKnownValue(value))
+            return;
+
+        throw new DeserializationException("Invalid enum value.");
+    }
+
     private {{enum|name}}() {}
 
 }

mojo/public/tools/bindings/generators/java_templates/header.java.tmpl

@@ -11,3 +11,4 @@
 package {{package}};
 
 import org.chromium.base.annotations.SuppressFBWarnings;
+import org.chromium.mojo.bindings.DeserializationException;

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

@@ -237,6 +237,10 @@ def _GetNameHierachy(kind):
   elements += _GetNameHierachy(kind)
   return '.'.join(elements)
 
+@contextfilter
+def GetJavaClassForEnum(context, kind):
+  return GetNameForKind(context, kind)
+
 def GetBoxedJavaType(context, kind, with_generics=True):
   unboxed_type = GetJavaType(context, kind, False, with_generics)
   if unboxed_type in _java_primitive_to_boxed_type:
@@ -416,6 +420,7 @@ class Generator(generator.Generator):
     'interface_response_name': GetInterfaceResponseName,
     'is_array_kind': mojom.IsArrayKind,
     'is_any_handle_kind': mojom.IsAnyHandleKind,
+    "is_enum_kind": mojom.IsEnumKind,
     'is_interface_request_kind': mojom.IsInterfaceRequestKind,
     'is_map_kind': mojom.IsMapKind,
     'is_nullable_kind': mojom.IsNullableKind,
@@ -424,6 +429,7 @@ class Generator(generator.Generator):
     'is_struct_kind': mojom.IsStructKind,
     'is_union_array_kind': IsUnionArrayKind,
     'is_union_kind': mojom.IsUnionKind,
+    'java_class_for_enum': GetJavaClassForEnum,
     'java_true_false': GetJavaTrueFalse,
     'java_type': GetJavaType,
     'method_ordinal_name': GetMethodOrdinalName,