Build external Java libs into standalone native libs.

CHANGELOG.md

@@ -6,6 +6,7 @@ https://github.com/j2objc-contrib/j2objc-gradle/compare/vA.B.C...vX.Y.Z
 ## vNext (HEAD)
 Functionality:
 * Automatic dependency resolution for Maven jars and Gradle projects #420
+* Build external Java libraries (with source) into standalone native libraries #431
 * Proper limitation of functionality on non-Mac platforms #396
 * Embedded docs and versioning info for easier debugging #395
 

src/main/groovy/com/github/j2objccontrib/j2objcgradle/DependencyConverter.groovy

@@ -26,8 +26,15 @@ import org.gradle.api.artifacts.SelfResolvingDependency
 
 /**
  * Converts `[test]compile` dependencies to their
- * `j2objcTranslation` and/or `j2objcLinkage` equivalents, depending on the type
- * of dependency and whether or not they are already provided in native code.
+ * `j2objcTranslationClosure` and/or `j2objcLinkage` equivalents, depending on the type
+ * of dependency and whether or not they are already provided in native code:
+ * <p/>
+ * External classfile .jar libraries you depend on via `compile` or `testCompile` will be
+ * converted to `j2objcTranslationClosure` dependencies of the corresponding source .jar libraries.
+ * Gradle projects you depend on via `compile` or `testCompile` will be converted to
+ * `j2objcLinkage` dependencies of the corresponding generated Objective C include headers
+ * and static library.  See {@link DependencyResolver} for details on the differences
+ * between these configurations.
  * <p/>
  * They will be resolved to appropriate `j2objc` constructs using DependencyResolver.
  */
@@ -79,7 +86,7 @@ class DependencyConverter {
     protected void visitSelfResolvingDependency(
             SelfResolvingDependency dep) {
         project.logger.debug("j2objc dependency converter: Translating file dep: $dep")
-        project.configurations.getByName('j2objcTranslation').dependencies.add(
+        project.configurations.getByName('j2objcTranslationClosure').dependencies.add(
                 dep.copy())
     }
 
@@ -103,12 +110,12 @@ class DependencyConverter {
         String group = dep.group == null ? '' : dep.group
         String version = dep.version == null ? '' : dep.version
         // TODO: Make this less fragile.  What if sources don't exist for this artifact?
-        project.dependencies.add('j2objcTranslation', "${group}:${dep.name}:${version}:sources")
+        project.dependencies.add('j2objcTranslationClosure', "${group}:${dep.name}:${version}:sources")
     }
 
     protected void visitGenericDependency(Dependency dep) {
         project.logger.warn("j2objc dependency converter: Unknown dependency type: $dep; copying naively")
-        project.configurations.getByName('j2objcTranslation').dependencies.add(
+        project.configurations.getByName('j2objcTranslationClosure').dependencies.add(
                 dep.copy())
     }
 }

src/main/groovy/com/github/j2objccontrib/j2objcgradle/DependencyResolver.groovy

@@ -15,19 +15,44 @@
  */
 
 package com.github.j2objccontrib.j2objcgradle
-
 import groovy.transform.CompileStatic
 import groovy.transform.PackageScope
 import org.gradle.api.InvalidUserDataException
 import org.gradle.api.Project
 import org.gradle.api.artifacts.Dependency
 import org.gradle.api.artifacts.ProjectDependency
 import org.gradle.api.artifacts.SelfResolvingDependency
+import org.gradle.api.file.DuplicatesStrategy
 import org.gradle.api.plugins.JavaPlugin
+import org.gradle.api.plugins.JavaPluginConvention
+import org.gradle.api.tasks.Copy
+import org.gradle.api.tasks.SourceSet
 import org.gradle.api.tasks.bundling.AbstractArchiveTask
-
+import org.gradle.api.tasks.util.PatternSet
 /**
- * Resolves `j2objcTranslation` and 'j2objcLinkage' dependencies into their `j2objc` constructs.
+ * Resolves `j2objc*` dependencies into their `j2objc` constructs:
+ * <p/>
+ * <ul>
+ * <li><b>j2objcTranslationClosure</b> - The plugin will translate only the subset of
+ * the configuration's source jars that are actually used by this project's
+ * code (via --build-closure), and
+ * compile and link the translated code directly into this project's libraries.
+ * Note that if multiple projects use j2objcTranslationClosure with the same
+ * external library, you will likely get duplicate symbol definition errors
+ * when linking them together.  Consider instead creating a separate Gradle
+ * project for that external library using j2objcTranslation.
+ * </li>
+ * <li><b>j2objcTranslation</b> - The plugin will translate the entire source jar
+ * provided in this configuration. Usually, this configuration is used
+ * to translate a single external Java library into a standalone Objective C library, that
+ * can then be linked (via j2objcLinkage) into your projects.
+ * </li>
+ * <li><b>j2objcLinkage</b> - The plugin will include the headers of, and link to
+ * the static library within, the referenced project.  Usually this configuration
+ * is used with other projects (your own, or external libraries translated
+ * with j2objcTranslation) that the J2ObjC Gradle Plugin has also been applied to.
+ * </li>
+ * </ul>
  */
 @PackageScope
 @CompileStatic
@@ -42,20 +67,59 @@ class DependencyResolver {
     }
 
     void configureAll() {
+        project.configurations.getByName('j2objcTranslationClosure').each { File it ->
+            // These are the resolved files, NOT the dependencies themselves.
+            // Usually source jars.
+            visitTranslationClosureFile(it)
+        }
         project.configurations.getByName('j2objcTranslation').each { File it ->
             // These are the resolved files, NOT the dependencies themselves.
-            visitTranslateFile(it)
+            // Usually source jars.
+            visitTranslationSourceJar(it)
         }
         project.configurations.getByName('j2objcLinkage').dependencies.each {
             visitLink(it)
         }
     }
 
-    protected void visitTranslateFile(File depFile) {
+    protected void visitTranslationClosureFile(File depFile) {
         j2objcConfig.translateSourcepaths(depFile.absolutePath)
         j2objcConfig.enableBuildClosure()
     }
 
+    private static final String EXTRACTION_TASK_NAME = 'j2objcTranslatedLibraryExtraction'
+
+    /**
+     * Adds to the main java sourceSet a to-be-generated directory that contains the contents
+     * of `j2objcTranslation` dependency libraries (if any).
+     */
+    static void configureSourceSets(Project project) {
+        JavaPluginConvention javaConvention = project.getConvention().getPlugin(JavaPluginConvention)
+        SourceSet sourceSet = javaConvention.sourceSets.findByName(SourceSet.MAIN_SOURCE_SET_NAME)
+        String dir = "${project.buildDir}/translationExtraction"
+        sourceSet.java.srcDirs(project.file(dir))
+        Copy copy = project.tasks.create(EXTRACTION_TASK_NAME, Copy,
+                {Copy task ->
+                    task.into(project.file(dir))
+                    // If two libraries define the same file, fail early.
+                    task.duplicatesStrategy = DuplicatesStrategy.FAIL
+                })
+        project.tasks.getByName(sourceSet.compileJavaTaskName).dependsOn(copy)
+    }
+
+    // Copy contents of sourceJarFile to build/translationExtraction
+    protected void visitTranslationSourceJar(File sourceJarFile) {
+        if (!sourceJarFile.absolutePath.endsWith('.jar')) {
+            String msg = "`j2objcTranslation` dependencies can only handle " +
+                         "source jar files, not ${sourceJarFile.absolutePath}"
+            throw new InvalidUserDataException(msg)
+        }
+        PatternSet pattern = new PatternSet()
+        pattern.include('**/*.java')
+        Copy copy = project.tasks.getByName(EXTRACTION_TASK_NAME) as Copy
+        copy.from(project.zipTree(sourceJarFile).matching(pattern))
+    }
+
     protected void visitLink(Dependency dep) {
         if (dep instanceof ProjectDependency) {
             visitLinkProjectDependency((ProjectDependency) dep)

src/main/groovy/com/github/j2objccontrib/j2objcgradle/J2objcConfig.groovy

@@ -323,11 +323,12 @@ class J2objcConfig {
     /**
      * @see #dependsOnJ2objcLib(org.gradle.api.Project)
      * @deprecated Use `dependencies { j2objcLinkage project(':beforeProjectName') }` or
-     * `autoConfigDeps = true` instead.
+     * `autoConfigureDeps = true` instead.
      */
     // TODO: Do this automatically based on project dependencies.
     @Deprecated
     void dependsOnJ2objcLib(String beforeProjectName) {
+        //noinspection GrDeprecatedAPIUsage
         dependsOnJ2objcLib(project.project(beforeProjectName))
     }
 
@@ -346,10 +347,10 @@ class J2objcConfig {
      * is preferable and sufficient.
      *
      * @deprecated Use `dependencies { j2objcLinkage project(':beforeProjectName') }` or
-     * `autoConfigDeps=true` instead.
+     * `autoConfigureDeps=true` instead.
      */
     // TODO: Phase this API out, and have J2ObjC-applied project dependencies controlled
-    // solely via `j2objcLink` configuration.
+    // solely via `j2objcLinkage` configuration.
     @CompileStatic(TypeCheckingMode.SKIP)
     @Deprecated
     void dependsOnJ2objcLib(Project beforeProject) {
@@ -671,6 +672,7 @@ class J2objcConfig {
     void testingOnlyPrepConfigurations() {
         // When testing we don't always want to apply the entire plugin
         // before calling finalConfigure.
+        project.configurations.create('j2objcTranslationClosure')
         project.configurations.create('j2objcTranslation')
         project.configurations.create('j2objcLinkage')
     }

src/main/groovy/com/github/j2objccontrib/j2objcgradle/J2objcPlugin.groovy

@@ -91,17 +91,33 @@ class J2objcPlugin implements Plugin<Project> {
                 // When j2objcConfig.autoConfigureDeps is true, this configuration
                 // will have source paths automatically added to it.  You can add
                 // *source* JARs/directories yourself as well.
-                j2objcTranslation {
+                j2objcTranslationClosure {
                     description = 'J2ObjC Java source dependencies that need to be ' +
-                                  'transitively translated via --build-closure'
+                                  'partially translated via --build-closure'
+                }
+
+                // If you want to translate an entire source library, regardless of which parts of the
+                // library code your own code depends on, use this configuration.  This
+                // will also cause the library to be Java compiled, since you cannot translate
+                // a library with j2objc that does not successfully compile in Java.
+                // So for example:
+                //   dependencies { j2objcTranslation 'com.google.code.gson:gson:2.3.1:sources' }
+                // will cause your project to produce a full gson Java classfile Jar AND a
+                // j2objc-translated static native library.
+                j2objcTranslation {
+                    description = 'J2ObjC Java source libraries that should be fully translated ' +
+                                  'and built as stand-alone native libraries'
                 }
+
                 // Currently, we can only handle Project dependencies already translated to Objective-C.
                 j2objcLinkage {
                     description = 'J2ObjC native library dependencies that need to be ' +
                                   'linked into the final library, and do not need translation'
                 }
             }
 
+            DependencyResolver.configureSourceSets(project)
+
             // Produces a modest amount of output
             logging.captureStandardOutput LogLevel.INFO
 

systemTests/externalLibrary1/base/build.gradle

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2015 the authors of j2objc-gradle (see AUTHORS file)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+apply plugin: 'java'
+apply plugin: 'com.github.j2objccontrib.j2objcgradle'
+
+repositories {
+    jcenter()
+}
+
+dependencies {
+    // Intentionally testing e2e use of a built-in j2objc library, Guava.
+    compile 'com.google.guava:guava:17.0'
+    // Normally we would reference this as compile "com.google.code.gson:gson:2.3.1"
+    compile project(':third_party_gson')
+    testCompile 'junit:junit:4.12'
+}
+
+j2objcConfig {
+    autoConfigureDeps true
+
+    finalConfigure()
+}

systemTests/externalLibrary1/base/src/main/java/com/example/Cube.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2015 the authors of j2objc-gradle (see AUTHORS file)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example;
+
+import com.google.common.base.Joiner;
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+public class Cube {
+
+    protected final int dimension;
+
+    public Cube(int dimension) {
+        this.dimension = dimension;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("[Cube %d]", dimension);
+    }
+
+    public String exerciseGuava() {
+        return Joiner.on(' ').join('a', 'b', 'c');
+    }
+
+    public String exerciseGson() {
+        Gson gson = new GsonBuilder().create();
+        return gson.toJson(new String[]{"a", "b", "c"});
+    }
+}

systemTests/externalLibrary1/base/src/test/java/com/example/CubeTest.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2015 the authors of j2objc-gradle (see AUTHORS file)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class CubeTest {
+
+    @Test
+    public void testToString() {
+        Assert.assertEquals("[Cube 7]", new Cube(7).toString());
+    }
+
+    @Test
+    public void testExerciseGuava() {
+        Assert.assertEquals("a b c", new Cube(7).exerciseGuava());
+    }
+
+    @Test
+    public void testExerciseGson() {
+        Assert.assertEquals("[\"a\",\"b\",\"c\"]", new Cube(7).exerciseGson());
+    }
+}

systemTests/externalLibrary1/build.gradle

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2015 the authors of j2objc-gradle (see AUTHORS file)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+buildscript {
+    repositories {
+        jcenter()
+    }
+    dependencies {
+        // This is the build output of the plugin itself.
+        classpath fileTree(dir: '../../build/libs', include: ['*.jar'])
+    }
+}
+
+allprojects {
+    apply plugin: 'java'
+    test {
+        testLogging {
+            // Provide full exception info on failure, instead
+            // of just pointing to an HTML file.
+            exceptionFormat = 'full'
+        }
+    }
+}