Generate java bindings for constants.

This CL is the first CL introducing java bindings. It only generates constants.

This is a reland of https://codereview.chromium.org/291903003 with a custom
DEPS file to fix bot issue.

TBR=viettrungluu@chromium.org,rmcilroy@chromium.org

Review URL: https://codereview.chromium.org/312643003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@274431 0039d316-1c4b-4281-b951-d872f2087c98

9 files changed, 267 insertions, 2 deletions

diff --git a/mojo/android/javatests/DEPS b/mojo/android/javatests/DEPS
new file mode 100644
index 0000000..78cf465
--- /dev/null
+++ b/mojo/android/javatests/DEPS
@@ -0,0 +1,4 @@
+include_rules = [
+  # out should be allowed by default, but bots are failing on this.
+  "+out",
+]
diff --git a/mojo/android/javatests/src/org/chromium/mojo/bindings/BindingsTest.java b/mojo/android/javatests/src/org/chromium/mojo/bindings/BindingsTest.java
new file mode 100644
index 0000000..1c4807b
--- /dev/null
+++ b/mojo/android/javatests/src/org/chromium/mojo/bindings/BindingsTest.java
@@ -0,0 +1,33 @@
+// 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.
+
+package org.chromium.mojo.bindings;
+
+import android.test.suitebuilder.annotation.SmallTest;
+
+import junit.framework.TestCase;
+
+import org.chromium.mojo.bindings.test.sample.SampleServiceConstants;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+
+/**
+ * Testing generated classes and associated features.
+ */
+public class BindingsTest extends TestCase {
+
+    /**
+     * Testing constants are correctly generated.
+     */
+    @SmallTest
+    public void testConstants() throws NoSuchFieldException, SecurityException {
+        assertEquals(3, SampleServiceConstants.THREE);
+        Field threeField = SampleServiceConstants.class.getField("THREE");
+        assertEquals(byte.class, threeField.getType());
+        assertEquals(Modifier.FINAL, threeField.getModifiers() & Modifier.FINAL);
+        assertEquals(Modifier.STATIC, threeField.getModifiers() & Modifier.STATIC);
+    }
+
+}
diff --git a/mojo/public/tools/bindings/generators/java_templates/constant_definition.tmpl b/mojo/public/tools/bindings/generators/java_templates/constant_definition.tmpl
new file mode 100644
index 0000000..f69f657
--- /dev/null
+++ b/mojo/public/tools/bindings/generators/java_templates/constant_definition.tmpl
@@ -0,0 +1,5 @@
+{% from "java_macros.tmpl" import build_default %}
+
+{% macro constant_def(constant) %}
+public static final {{constant.kind|java_type}} {{constant|name}} = {{build_default(module, constant.kind, constant.value)|indent(4)}};
+{% endmacro %}
diff --git a/mojo/public/tools/bindings/generators/java_templates/constants.java.tmpl b/mojo/public/tools/bindings/generators/java_templates/constants.java.tmpl
new file mode 100644
index 0000000..0a4e299
--- /dev/null
+++ b/mojo/public/tools/bindings/generators/java_templates/constants.java.tmpl
@@ -0,0 +1,12 @@
+{% from "constant_definition.tmpl" import constant_def %}
+{% include "header.java.tmpl" %}
+
+public final class {{main_entity}} {
+{%  for constant in constants %}
+
+    {{constant_def(constant)|indent(4)}}
+{%  endfor %}
+
+    private {{main_entity}}() {}
+
+}
diff --git a/mojo/public/tools/bindings/generators/java_templates/header.java.tmpl b/mojo/public/tools/bindings/generators/java_templates/header.java.tmpl
new file mode 100644
index 0000000..ec6a88b
--- /dev/null
+++ b/mojo/public/tools/bindings/generators/java_templates/header.java.tmpl
@@ -0,0 +1,11 @@
+// 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.
+
+// This file is autogenerated by:
+//     mojo/public/tools/bindings/mojom_bindings_generator.py
+// For:
+//     {{module.path}}
+//
+
+package {{package}};
diff --git a/mojo/public/tools/bindings/generators/java_templates/java_macros.tmpl b/mojo/public/tools/bindings/generators/java_templates/java_macros.tmpl
new file mode 100644
index 0000000..a8745d2
--- /dev/null
+++ b/mojo/public/tools/bindings/generators/java_templates/java_macros.tmpl
@@ -0,0 +1,3 @@
+{%  macro build_default(module, kind, value) %}
+({{kind|java_type}}) {{value|expression_to_text(module)}}
+{%  endmacro %}
diff --git a/mojo/public/tools/bindings/generators/mojom_java_generator.py b/mojo/public/tools/bindings/generators/mojom_java_generator.py
new file mode 100644
index 0000000..0b38127
--- /dev/null
+++ b/mojo/public/tools/bindings/generators/mojom_java_generator.py
@@ -0,0 +1,182 @@
+# 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
+
+import mojom.generate.generator as generator
+import mojom.generate.module as mojom
+from mojom.generate.template_expander import UseJinja
+
+
+GENERATOR_PREFIX = 'java'
+
+_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',
+}
+
+
+def NameToComponent(name):
+  # insert '_' between anything and a Title name (e.g, HTTPEntry2FooBar ->
+  # HTTP_Entry2_FooBar)
+  name = re.sub('([^_])([A-Z][^A-Z_]+)', r'\1_\2', name)
+  # insert '_' between non upper and start of upper blocks (e.g.,
+  # HTTP_Entry2_FooBar -> HTTP_Entry2_Foo_Bar)
+  name = re.sub('([^A-Z_])([A-Z])', r'\1_\2', name)
+  return [x.lower() for x in name.split('_')]
+
+def CapitalizeFirst(string):
+  return string[0].upper() + string[1:]
+
+def UpperCamelCase(name):
+  return ''.join([CapitalizeFirst(x) for x in NameToComponent(name)])
+
+def CamelCase(name):
+  uccc = UpperCamelCase(name)
+  return uccc[0].lower() + uccc[1:]
+
+def ConstantStyle(name):
+  components = NameToComponent(name)
+  if components[0] == 'k':
+    components = components[1:]
+  return '_'.join([x.upper() for x in components])
+
+def GetNameForElement(element):
+  if (isinstance(element, mojom.Enum) or
+      isinstance(element, mojom.Interface) or
+      isinstance(element, mojom.Struct)):
+    return UpperCamelCase(element.name)
+  if (isinstance(element, mojom.Method) or
+      isinstance(element, mojom.Parameter) or
+      isinstance(element, mojom.Field)):
+    return CamelCase(element.name)
+  if isinstance(element,  mojom.EnumValue):
+    return (UpperCamelCase(element.enum_name) + '.' +
+            ConstantStyle(element.name))
+  if (isinstance(element, mojom.NamedValue) or
+      isinstance(element, mojom.Constant)):
+    return ConstantStyle(element.name)
+  raise Exception("Unexpected element: " % element)
+
+def GetPackage(module):
+  if 'JavaPackage' in module.attributes:
+    package = module.attributes['JavaPackage']
+    if isinstance(package, basestring):
+      return package
+    assert package[0] == 'EXPRESSION'
+    assert len(package[1]) == 1
+    return package[1][0][1:-1].encode('string_escape')
+  # Default package.
+  return "org.chromium.mojom." + module.namespace
+
+def GetNameForKind(kind):
+  def _GetNameHierachy(kind):
+    hierachy = []
+    if kind.parent_kind:
+      hierachy = _GetNameHierachy(kind.parent_kind)
+    hierachy.append(kind.name)
+    return hierachy
+
+  elements = [GetPackage(kind.module)]
+  elements += _GetNameHierachy(kind)
+  return '.'.join(elements)
+
+def GetJavaType(kind):
+  if isinstance(kind, (mojom.Struct, mojom.Interface)):
+    return GetNameForKind(kind)
+  if isinstance(kind, mojom.Array):
+    return "%s[]" % GetJavaType(kind.kind)
+  if isinstance(kind, mojom.Enum):
+    return "int"
+  return _spec_to_java_type[kind.spec]
+
+def TranslateConstants(token, module):
+  def _TranslateNamedValue(named_value):
+    entity_name = GetNameForElement(named_value)
+    if named_value.parent_kind:
+      return GetJavaType(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)
+    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 ExpressionToText(value, module):
+  if value[0] != "EXPRESSION":
+    raise Exception("Expected EXPRESSION, got" + value)
+  return "".join(generator.ExpressionMapper(value,
+      lambda token: TranslateConstants(token, module)))
+
+def GetConstantsMainEntityName(module):
+  # 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 = {
+    "expression_to_text": ExpressionToText,
+    "java_type": GetJavaType,
+    "name": GetNameForElement,
+    "verify_token_type": generator.VerifyTokenType,
+  }
+
+  def GetJinjaExports(self):
+    return {
+      "module": self.module,
+      "package": GetPackage(self.module),
+    }
+
+  @UseJinja("java_templates/constants.java.tmpl", filters=java_filters,
+            lstrip_blocks=True, trim_blocks=True)
+  def GenerateConstantsSource(self, module):
+    exports = self.GetJinjaExports()
+    exports.update({"main_entity": GetConstantsMainEntityName(module),
+                    "constants": module.constants})
+    return exports
+
+  def GenerateFiles(self, unparsed_args):
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--java_output_directory", dest="java_output_directory")
+    args = parser.parse_args(unparsed_args)
+    if self.output_dir and args.java_output_directory:
+      self.output_dir = os.path.join(args.java_output_directory,
+                                     GetPackage(self.module).replace('.', '/'))
+      if not os.path.exists(self.output_dir):
+        try:
+          os.makedirs(self.output_dir)
+        except:
+          # Ignore errors on directory creation.
+          pass
+
+    if self.module.constants:
+      self.Write(self.GenerateConstantsSource(self.module),
+                 "%s.java" % GetConstantsMainEntityName(self.module))
diff --git a/mojo/public/tools/bindings/mojom_bindings_generator.gypi b/mojo/public/tools/bindings/mojom_bindings_generator.gypi
index 3fe0c63..dcb273dd 100644
--- a/mojo/public/tools/bindings/mojom_bindings_generator.gypi
+++ b/mojo/public/tools/bindings/mojom_bindings_generator.gypi
@@ -5,13 +5,14 @@
 {
   'rules': [
     {
-      'rule_name': 'Generate C++ source files from mojom files',
+      'rule_name': 'Generate C++, JS and Java source files from mojom files',
       'extension': 'mojom',
       'variables': {
         'mojom_base_output_dir':
              '<!(python <(DEPTH)/build/inverse_depth.py <(DEPTH))',
         'mojom_bindings_generator':
             '<(DEPTH)/mojo/public/tools/bindings/mojom_bindings_generator.py',
+        'java_out_dir': '<(PRODUCT_DIR)/java_mojo/<(_target_name)/src',
       },
       'inputs': [
         '<(mojom_bindings_generator)',
@@ -34,11 +35,16 @@
         '<(DEPTH)/mojo/public/tools/bindings/generators/cpp_templates/struct_serialization_definition.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/cpp_templates/wrapper_class_declaration.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/cpp_templates/wrapper_class_definition.tmpl',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/java_templates/constant_definition.tmpl',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/java_templates/constants.java.tmpl',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/java_templates/header.java.tmpl',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/java_templates/java_macros.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/enum_definition.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/interface_definition.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/module.js.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/struct_definition.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_cpp_generator.py',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_java_generator.py',
         '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_js_generator.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/__init__.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/error.py',
@@ -66,6 +72,7 @@
         '--use_chromium_bundled_pylibs',
         '-d', '<(DEPTH)',
         '-o', '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)',
+        '--java_output_directory=<(java_out_dir)',
       ],
       'message': 'Generating Mojo bindings from <(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom',
       'process_outputs_as_sources': 1,
@@ -80,6 +87,11 @@
       '<(DEPTH)',
       '<(SHARED_INTERMEDIATE_DIR)',
     ],
+    'variables': {
+      'generated_src_dirs': [
+        '<(PRODUCT_DIR)/java_mojo/<(_target_name)/src',
+      ],
+    },
   },
   'hard_dependency': 1,
 }
diff --git a/mojo/public/tools/bindings/mojom_bindings_generator.py b/mojo/public/tools/bindings/mojom_bindings_generator.py
index aee3b8c..9332576 100755
--- a/mojo/public/tools/bindings/mojom_bindings_generator.py
+++ b/mojo/public/tools/bindings/mojom_bindings_generator.py
@@ -53,6 +53,9 @@ def LoadGenerators(generators_string):
     elif generator_name.lower() == "javascript":
       generator_name = os.path.join(script_dir, "generators",
                                     "mojom_js_generator.py")
+    elif generator_name.lower() == "java":
+      generator_name = os.path.join(script_dir, "generators",
+                                    "mojom_java_generator.py")
     # Specified generator python module:
     elif generator_name.endswith(".py"):
       pass
@@ -153,7 +156,7 @@ def main():
   parser.add_argument("-o", "--output_dir", dest="output_dir", default=".",
                       help="output directory for generated files")
   parser.add_argument("-g", "--generators", dest="generators_string",
-                      metavar="GENERATORS", default="c++,javascript",
+                      metavar="GENERATORS", default="c++,javascript,java",
                       help="comma-separated list of generators")
   parser.add_argument("--debug_print_intermediate", action="store_true",
                       help="print the intermediate representation")