Bug 1444546 - Part 2: Build annotationProcessors with Gradle. r=jchen

We want annotationProcessors to be compiled and archived into a JAR at
build time, ready to generate JNI wrappers.  (That is, until we turn
the whole thing into a real annotation processor.)  But even if we do
use a real annotation processor, we still need to generate SDK
bindings, which is less clearly expressed as an annotation processor.
(It's more of a build step.)

Gradle provides a huge number of ways to organize build logic to
achieve this: see
https://docs.gradle.org/current/userguide/organizing_build_logic.html.
Unfortunately, the best such way -- putting the code into
$topsrcdir/buildSrc -- has key disadvantages:

1) it pollutes the top-level $topsrcdir, and there's no way to change the
location of buildSrc (https://github.com/gradle/gradle/issues/2472);

2) it's complicated to have a dependent project
(mobile/android/annotations) expose its code via a buildSrc project;

3) using buildSrc at all appears to conflict with the Android-Gradle
plugin version that we are using.

Therefore, this commit does something much simpler: it adds a
Java-only project and uses the resulting Gradle "Jar" task and archive
output as input to the existing Gradle "generate JNI wrappers" task.

MozReview-Commit-ID: 2OyYLPneE1M

--HG--
extra : rebase_source : d99b74a0a1e0bb3e8f4d4540978328388e5c2e42

build/annotationProcessors/Makefile.in

@@ -1,10 +0,0 @@
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-include $(topsrcdir)/config/rules.mk
-
-# Include Android specific java flags, instead of what's in rules.mk.
-include $(topsrcdir)/config/android-common.mk
-
-export:: annotationProcessors.jar

build/annotationProcessors/moz.build

@@ -1,21 +0,0 @@
-# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
-# vim: set filetype=python:
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-jar = add_java_jar('annotationProcessors')
-jar.sources += [
-    'AnnotationInfo.java',
-    'AnnotationProcessor.java',
-    'classloader/AnnotatableEntity.java',
-    'classloader/ClassWithOptions.java',
-    'classloader/IterableJarLoadingURLClassLoader.java',
-    'classloader/JarClassIterator.java',
-    'CodeGenerator.java',
-    'SDKProcessor.java',
-    'utils/AlphabeticAnnotatableEntityComparator.java',
-    'utils/GeneratableElementIterator.java',
-    'utils/Utils.java',
-]
-jar.extra_jars += CONFIG['ANDROID_LINT_CLASSPATH'].split()

build/moz.build

@@ -24,9 +24,6 @@ CRAMTEST_MANIFESTS += [
     'tests/cram/cram.ini',
 ]
 
-if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'android':
-    DIRS += ['annotationProcessors']
-
 DEFINES['ACCEPTED_MAR_CHANNEL_IDS'] = CONFIG['ACCEPTED_MAR_CHANNEL_IDS']
 
 if CONFIG['MOZ_BUILD_APP'] == 'browser':

config/recurse.mk

@@ -165,9 +165,6 @@ ifeq (.,$(DEPTH))
 js/xpconnect/src/export: dom/bindings/export xpcom/xpidl/export
 accessible/xpcom/export: xpcom/xpidl/export
 
-# The widget binding generator code is part of the annotationProcessors.
-widget/android/bindings/export: build/annotationProcessors/export
-
 # .xpt generation needs the xpidl lex/yacc files
 xpcom/xpidl/export: xpcom/idl-parser/xpidl/export
 

mobile/android/annotations/build.gradle

@@ -0,0 +1,11 @@
+buildDir "${topobjdir}/gradle/build/mobile/android/annotations"
+
+apply plugin: 'java'
+
+dependencies {
+    compile 'com.android.tools.lint:lint:25.3.1'
+    compile 'com.android.tools.lint:lint-checks:25.3.1'
+}
+
+sourceCompatibility = JavaVersion.VERSION_1_8
+targetCompatibility = JavaVersion.VERSION_1_8

mobile/android/gradle/with_gecko_binaries.gradle

@@ -119,6 +119,8 @@ ext.configureLibraryVariantWithJNIWrappers = { variant, module ->
     def jarTask = tasks["transformClassesAndResourcesWithPrepareIntermediateJarsFor${variant.name.capitalize()}"]
     def output = jarTask.outputs.files.find({ it.absolutePath.contains('/classes.jar') })
 
+    def annotationProcessorsJarTask = project(':annotations').jar
+
     def wrapperTask
     if (System.env.IS_LANGUAGE_REPACK == '1') {
         // Single-locale l10n repacks set `IS_LANGUAGE_REPACK=1` and don't
@@ -126,7 +128,7 @@ ext.configureLibraryVariantWithJNIWrappers = { variant, module ->
         wrapperTask = task("generateJNIWrappersFor${module}${variant.name.capitalize()}")
     } else {
         wrapperTask = task("generateJNIWrappersFor${module}${variant.name.capitalize()}", type: JavaExec) {
-            classpath "${topobjdir}/build/annotationProcessors/annotationProcessors.jar"
+            classpath annotationProcessorsJarTask.archivePath
         
             // Configure the classpath at evaluation-time, not at
             // configuration-time: see above comment.
@@ -143,6 +145,7 @@ ext.configureLibraryVariantWithJNIWrappers = { variant, module ->
             workingDir "${topobjdir}/mobile/android/base"
             
             dependsOn jarTask
+            dependsOn annotationProcessorsJarTask
         }
     }
 
@@ -157,6 +160,8 @@ ext.configureApplicationVariantWithJNIWrappers = { variant, module ->
     def jarTask = tasks["bundleAppClasses${variant.name.capitalize()}"]
     def output = jarTask.outputs.files.find({ it.absolutePath.contains('/classes.jar') })
 
+    def annotationProcessorsJarTask = project(':annotations').jar
+
     def wrapperTask
     if (System.env.IS_LANGUAGE_REPACK == '1') {
         // Single-locale l10n repacks set `IS_LANGUAGE_REPACK=1` and don't
@@ -164,7 +169,7 @@ ext.configureApplicationVariantWithJNIWrappers = { variant, module ->
         wrapperTask = task("generateJNIWrappersFor${module}${variant.name.capitalize()}")
     } else {
         wrapperTask = task("generateJNIWrappersFor${module}${variant.name.capitalize()}", type: JavaExec) {
-            classpath "${topobjdir}/build/annotationProcessors/annotationProcessors.jar"
+            classpath annotationProcessorsJarTask.archivePath
         
             // Configure the classpath at evaluation-time, not at
             // configuration-time: see above comment.
@@ -182,6 +187,8 @@ ext.configureApplicationVariantWithJNIWrappers = { variant, module ->
     
             // This forces bundling, which isn't usually part of the assemble* process.
             dependsOn jarTask
+
+            dependsOn annotationProcessorsJarTask
         }
     }
 }

settings.gradle

@@ -14,6 +14,7 @@ if (proc.exitValue() != 0) {
 }
 
 import groovy.json.JsonSlurper
+
 def slurper = new JsonSlurper()
 def json = slurper.parseText(standardOutput.toString())
 
@@ -28,12 +29,14 @@ if (json.substs.MOZ_BUILD_APP != 'mobile/android') {
 // but it's hard to automatically arrange better.
 System.setProperty('android.home', json.substs.ANDROID_SDK_ROOT)
 
+include ':annotations'
 include ':app'
 include ':geckoview'
 include ':geckoview_example'
 include ':omnijar'
 include ':thirdparty'
 
+project(':annotations').projectDir = new File("${json.topsrcdir}/mobile/android/annotations")
 project(':app').projectDir = new File("${json.topsrcdir}/mobile/android/app")
 project(':geckoview').projectDir = new File("${json.topsrcdir}/mobile/android/geckoview")
 project(':geckoview_example').projectDir = new File("${json.topsrcdir}/mobile/android/geckoview_example")