Add serialization/deserialization of structs for mojo java bindings.

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

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Generates java source files from a mojom.Module."""
 
 import argparse
 import os
 import re
 
 from jinja2 import contextfilter
 
 import mojom.generate.generator as generator
 import mojom.generate.module as mojom
 from mojom.generate.template_expander import UseJinja
 
 
 GENERATOR_PREFIX = 'java'
 
+_HEADER_SIZE = 8
+
 _spec_to_java_type = {
   'b':     'boolean',
   'd':     'double',
   'f':     'float',
   'h:d:c': 'org.chromium.mojo.system.DataPipe.ConsumerHandle',
   'h:d:p': 'org.chromium.mojo.system.DataPipe.ProducerHandle',
   'h:m':   'org.chromium.mojo.system.MessagePipeHandle',
   'h':     'org.chromium.mojo.system.UntypedHandle',
   'h:s':   'org.chromium.mojo.system.SharedBufferHandle',
   'i16':   'short',
   'i32':   'int',
   'i64':   'long',
   'i8':    'byte',
   's':     'String',
   'u16':   'short',
   'u32':   'int',
   'u64':   'long',
   'u8':    'byte',
 }
 
+_spec_to_decode_method = {
+  'b':     'readBoolean',
+  'd':     'readDouble',
+  'f':     'readFloat',
+  'h:d:c': 'readConsumerHandle',
+  'h:d:p': 'readProducerHandle',
+  'h:m':   'readMessagePipeHandle',
+  'h':     'readUntypedHandle',
+  'h:s':   'readSharedBufferHandle',
+  'i16':   'readShort',
+  'i32':   'readInt',
+  'i64':   'readLong',
+  'i8':    'readByte',
+  's':     'readString',
+  'u16':   'readShort',
+  'u32':   'readInt',
+  'u64':   'readLong',
+  'u8':    'readByte',
+}
+
 _java_primitive_to_boxed_type = {
   'boolean': 'Boolean',
   'byte':    'Byte',
   'double':  'Double',
   'float':   'Float',
   'int':     'Integer',
   'long':    'Long',
   'short':   'Short',
 }
 
@@ skipping 42 matching lines @@
     return ConstantStyle(element.name)
   raise Exception("Unexpected element: " % element)
 
 def GetInterfaceResponseName(method):
   return UpperCamelCase(method.name + 'Response')
 
 def ParseStringAttribute(attribute):
   assert isinstance(attribute, basestring)
   return attribute
 
+def IsArray(kind):
+  return isinstance(kind, (mojom.Array, mojom.FixedArray))
+
+@contextfilter
+def DecodeMethod(context, kind, offset, bit):
+  def _DecodeMethodName(kind):
+    if IsArray(kind):
+      return _DecodeMethodName(kind.kind) + 's'
+    if isinstance(kind, mojom.Enum):
+      return _DecodeMethodName(mojom.INT32)
+    if isinstance(kind, mojom.InterfaceRequest):
+      return "readInterfaceRequest"
+    if isinstance(kind, mojom.Interface):
+      return "readServiceInterface"
+    return _spec_to_decode_method[kind.spec]
+  methodName = _DecodeMethodName(kind)
+  additionalParams = ''
+  if (kind == mojom.BOOL):
+    additionalParams = ', %d' % bit
+  if (isinstance(kind, mojom.Interface) or
+      (IsArray(kind) and
+       isinstance(kind.kind, mojom.Interface))):
+    interfaceKind = kind
+    if IsArray(kind):
+      interfaceKind = kind.kind
+    additionalParams = ', %s.BUILDER' % GetJavaType(context, interfaceKind)

[rmcilroy, 2014/06/25 13:14:40]

I think this would be clearer as:
  if isinstance(kind, mojom.Interface: 
    additionalParams = ', %s.BUILDER' % GetJavaType(context, kind)
  if (IsArray(kind) and isinstance(kind.kind, mojom.Interface)):
    additionalParams = ', %s.BUILDER' % GetJavaType(context, kind.kind)

[qsr, 2014/06/25 14:43:06]

Done.

+  return '%s(%s%s)' % (methodName, offset, additionalParams)
+
+@contextfilter
+def EncodeMethod(context, kind, variable, offset, bit):
+  additionalParams = ''
+  if (kind == mojom.BOOL):
+    additionalParams = ', %d' % bit
+  if (isinstance(kind, mojom.Interface) or
+      (IsArray(kind) and
+       isinstance(kind.kind, mojom.Interface))):
+    interfaceKind = kind
+    if IsArray(kind):
+      interfaceKind = kind.kind
+    additionalParams = ', %s.BUILDER' % GetJavaType(context, interfaceKind)

[rmcilroy, 2014/06/25 13:14:40]

ditto

[qsr, 2014/06/25 14:43:06]

Done.

+  return 'encode(%s, %s%s)' % (variable, offset, additionalParams)
+
 def GetPackage(module):
   if 'JavaPackage' in module.attributes:
     return ParseStringAttribute(module.attributes['JavaPackage'])
   # Default package.
   return "org.chromium.mojom." + module.namespace
 
 def GetNameForKind(context, kind):
   def _GetNameHierachy(kind):
     hierachy = []
     if kind.parent_kind:
@@ skipping 16 matching lines @@
 
 @contextfilter
 def GetJavaType(context, kind, boxed=False):
   if boxed:
     return GetBoxedJavaType(context, kind)
   if isinstance(kind, (mojom.Struct, mojom.Interface)):
     return GetNameForKind(context, kind)
   if isinstance(kind, mojom.InterfaceRequest):
     return ("org.chromium.mojo.bindings.InterfaceRequest<%s>" %
             GetNameForKind(context, kind.kind))
-  if isinstance(kind, (mojom.Array, mojom.FixedArray)):
+  if IsArray(kind):
     return "%s[]" % GetJavaType(context, kind.kind)
   if isinstance(kind, mojom.Enum):
     return "int"
   return _spec_to_java_type[kind.spec]
 
 def IsHandle(kind):
   return kind.spec[0] == 'h'
 
 @contextfilter
 def DefaultValue(context, field):
   assert field.default
   if isinstance(field.kind, mojom.Struct):
     assert field.default == "default"
     return "new %s()" % GetJavaType(context, field.kind)
   return "(%s) %s" % (GetJavaType(context, field.kind),
                       ExpressionToText(context, field.default))
 
 @contextfilter
+def NewArray(context, kind, size):
+  if IsArray(kind.kind):
+    return NewArray(context, kind.kind, size) + '[]'
+  return 'new %s[%s]' % (GetJavaType(context, kind.kind), size)
+
+@contextfilter
 def ExpressionToText(context, token):
   def _TranslateNamedValue(named_value):
     entity_name = GetNameForElement(named_value)
     if named_value.parent_kind:
       return GetJavaType(context, named_value.parent_kind) + '.' + entity_name
     # Handle the case where named_value is a module level constant:
     if not isinstance(named_value, mojom.EnumValue):
       entity_name = (GetConstantsMainEntityName(named_value.module) + '.' +
                       entity_name)
     if GetPackage(named_value.module) == GetPackage(context.resolve('module')):
       return entity_name
     return GetPackage(named_value.module) + '.' + entity_name
 
   if isinstance(token, mojom.NamedValue):
     return _TranslateNamedValue(token)
   # Add Long suffix to all number literals.
   if re.match('^[0-9]+$', token):
     return token + 'L'
   return token
 
+def IsPointerArrayKind(kind):
+  if not IsArray(kind):
+    return False
+  sub_kind = kind.kind
+  return generator.IsObjectKind(sub_kind)
+
 def GetConstantsMainEntityName(module):
   if 'JavaConstantsClassName' in module.attributes:
     return ParseStringAttribute(module.attributes['JavaConstantsClassName'])
   # This constructs the name of the embedding classes for module level constants
   # by extracting the mojom's filename and prepending it to Constants.
   return (UpperCamelCase(module.path.split('/')[-1].rsplit('.', 1)[0]) +
           'Constants')
 
 class Generator(generator.Generator):
 
   java_filters = {
     "interface_response_name": GetInterfaceResponseName,
     "default_value": DefaultValue,
+    "decode_method": DecodeMethod,
     "expression_to_text": ExpressionToText,
+    "encode_method": EncodeMethod,
     "is_handle": IsHandle,
+    "is_pointer_array_kind": IsPointerArrayKind,
+    "is_struct_kind": lambda kind: isinstance(kind, mojom.Struct),
     "java_type": GetJavaType,
     "name": GetNameForElement,
+    "new_array": NewArray,
+    "struct_size": lambda ps: ps.GetTotalSize() + _HEADER_SIZE,
   }
 
   def GetJinjaExports(self):
     return {
       "module": self.module,
       "package": GetPackage(self.module),
     }
 
   @UseJinja("java_templates/enum.java.tmpl", filters=java_filters)
   def GenerateEnumSource(self, enum):
@@ skipping 57 matching lines @@
   def GetJinjaParameters(self):
     return {
       'lstrip_blocks': True,
       'trim_blocks': True,
     }
 
   def GetGlobals(self):
     return {
       'module': self.module,
     }