Do not proc apt if possible (#232)

We can determine that an external dependency is an annotation processor if there's "META-INF/services/javax.annotation.processing.Processor" in the jar, allowing us to avoid unpacking and transpiling it. Processors declared in the reactor continue to build and run as normal, and need not be packaged in a jar. Co-authored-by: Colin Alworth <[email protected]>
Vertispan · Feb 1, 2024 · 320e5ba · 320e5ba
1 parent 62aac38
commit 320e5ba
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diff --git a/build-caching/src/main/java/com/vertispan/j2cl/build/Project.java b/build-caching/src/main/java/com/vertispan/j2cl/build/Project.java
@@ -1,6 +1,16 @@
 package com.vertispan.j2cl.build;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
 
 /**
  * Represents a set of sources and the dependencies used to build them. The sourceRoots property
@@ -15,6 +25,10 @@ public class Project implements com.vertispan.j2cl.build.task.Project {
 
     private boolean isJsZip = false;
 
+    private File jar;
+
+    private Set<String> processors;
+
     public Project(String key) {
         this.key = key;
     }
@@ -82,4 +96,36 @@ public void markJsZip() {
     public boolean isJsZip() {
         return isJsZip;
     }
+
+    @Override
+    public File getJar() {
+        return jar;
+    }
+
+    public void setJar(File jar) {
+        this.jar = jar;
+    }
+
+    @Override
+    public Set<String> getProcessors() {
+        if (processors == null) {
+            if (jar == null || isJsZip() || hasSourcesMapped()) {
+                processors = Collections.emptySet();
+            } else if (jar.exists()) {
+                processors = new HashSet<>();
+                try (ZipFile zipFile = new ZipFile(jar)) {
+                    ZipEntry entry = zipFile.getEntry("META-INF/services/javax.annotation.processing.Processor");
+                    if (entry != null) {
+                        try (InputStreamReader inputStreamReader = new InputStreamReader(zipFile.getInputStream(entry), StandardCharsets.UTF_8);
+                             BufferedReader bufferedReader = new BufferedReader(inputStreamReader)) {
+                            bufferedReader.lines().forEach(line -> processors.add(line.trim()));
+                        }
+                    }
+                } catch (IOException e) {
+                    throw new RuntimeException(e);
+                }
+            }
+        }
+        return processors;
+    }
 }
diff --git a/build-caching/src/main/java/com/vertispan/j2cl/build/task/Project.java b/build-caching/src/main/java/com/vertispan/j2cl/build/task/Project.java
@@ -1,6 +1,8 @@
 package com.vertispan.j2cl.build.task;
 
+import java.io.File;
 import java.util.List;
+import java.util.Set;
 
 /**
  *
@@ -19,4 +21,18 @@ public interface Project {
      * @return true if this project should only be used for its JS content, false otherwise
      */
     boolean isJsZip();
+
+    /**
+     * If this dependency is a maven external dependency, return the jar file that represents it.
+     * @return File pointing at the jar, or null if this is a maven reactor project.
+     */
+    File getJar();
+
+    /**
+     *  If this project is a maven external dependency and has an annotation processors in it,
+     *  return the set of declared processors. If this is a maven reactor project (with annotataion processor or not),
+     *  return an empty set.
+     */
+    Set<String> getProcessors();
+
 }
diff --git a/j2cl-maven-plugin/src/main/java/com/vertispan/j2cl/mojo/AbstractBuildMojo.java b/j2cl-maven-plugin/src/main/java/com/vertispan/j2cl/mojo/AbstractBuildMojo.java
@@ -324,6 +324,8 @@ private Project buildProjectHelper(MavenProject mavenProject, Artifact artifact,
                 }
             }
 
+            child.setJar(mavenDependency.getFile());
+
             // construct a dependency node for this, and attach it to the new project
             Dependency dep = new Dependency();
             dep.setProject(child);
@@ -406,7 +408,7 @@ protected TaskRegistry createTaskRegistry() {
     protected Predicate<String> withSourceRootFilter() {
         return path -> new File(path).exists() &&
             !(annotationProcessorMode.pluginShouldExcludeGeneratedAnnotationsDir()
-                && (path.endsWith("generated-test-sources" + File.separator + "test-annotations") || 
+                && (path.endsWith("generated-test-sources" + File.separator + "test-annotations") ||
                     path.endsWith("generated-sources" + File.separator + "annotations")));
     }
 

diff --git a/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/BytecodeTask.java b/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/BytecodeTask.java
@@ -6,12 +6,21 @@
 import com.vertispan.j2cl.tools.Javac;
 
 import javax.annotation.Nullable;
+import java.io.BufferedReader;
 import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.PathMatcher;
+import java.nio.file.Paths;
+import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -29,6 +38,9 @@ public class BytecodeTask extends TaskFactory {
     public static final PathMatcher JAVA_BYTECODE = withSuffix(".class");
     public static final PathMatcher NOT_BYTECODE = p -> !JAVA_BYTECODE.matches(p);
 
+    public static final PathMatcher APT_PROCESSOR = p ->
+                        p.equals(Paths.get("META-INF", "services", "javax.annotation.processing.Processor"));
+
     @Override
     public String getOutputType() {
         return OutputTypes.BYTECODE;
@@ -67,14 +79,43 @@ public Task resolve(Project project, Config config) {
         // be if we had built a jar
         Input resources = input(project, OutputTypes.INPUT_SOURCES).filter(NOT_BYTECODE);
 
-        List<Input> bytecodeClasspath = scope(project.getDependencies(), com.vertispan.j2cl.build.task.Dependency.Scope.COMPILE)
+        List<Input> bytecodeClasspath = scope(project.getDependencies()
+                        .stream()
+                        .filter(dependency -> dependency.getProject().getProcessors().isEmpty()).collect(Collectors.toSet()),
+                com.vertispan.j2cl.build.task.Dependency.Scope.COMPILE)
                 .stream()
                 .map(inputs(OutputTypes.BYTECODE))
                 .collect(Collectors.toUnmodifiableList());
 
+        List<Input> inReactorProcessors = scope(project.getDependencies().stream().filter(dependency -> dependency.getProject().hasSourcesMapped()
+                        && !dependency.getProject().isJsZip()).collect(Collectors.toSet()),
+                com.vertispan.j2cl.build.task.Dependency.Scope.COMPILE)
+                .stream()
+                .map(inputs(OutputTypes.BYTECODE))
+                .map(input -> input.filter(APT_PROCESSOR))
+                .collect(Collectors.toUnmodifiableList());
+
         File bootstrapClasspath = config.getBootstrapClasspath();
-        List<File> extraClasspath = config.getExtraClasspath();
+        List<File> extraClasspath = new ArrayList<>(config.getExtraClasspath());
+        Set<String> processors = new HashSet<>();
+        project.getDependencies()
+                .stream()
+                .map(d -> d.getProject())
+                .filter(p -> !p.getProcessors().isEmpty())
+                .forEach(p -> {
+                    processors.addAll(p.getProcessors());
+                    extraClasspath.add(p.getJar());
+                });
+
         return context -> {
+            /* we don't know if reactor dependency project is apt, before it's compiled, so we need to check it on the fly
+               1) there are no processors in the project, so we pass empty set to javac, nothing happens
+               2) there are only reactor processors, so we pass empty set to javac, they will be triggered by javac
+               3) thee are both reactor and non-reactor processors, so we pass both to javac via set
+               4) there are only non-reactor processors, we pass them to javac via set
+             */
+            Set<String> aptProcessors = maybeAddInReactorAptProcessor(inReactorProcessors, processors);
+
             if (!inputSources.getFilesAndHashes().isEmpty()) {
                 // At least one .java file in sources, compile it (otherwise skip this and just copy resource)
 
@@ -86,7 +127,7 @@ public Task resolve(Project project, Config config) {
                 List<File> sourcePaths = inputDirs.getParentPaths().stream().map(Path::toFile).collect(Collectors.toUnmodifiableList());
                 File generatedClassesDir = getGeneratedClassesDir(context);
                 File classOutputDir = context.outputPath().toFile();
-                Javac javac = new Javac(context, generatedClassesDir, sourcePaths, classpathDirs, classOutputDir, bootstrapClasspath);
+                Javac javac = new Javac(context, generatedClassesDir, sourcePaths, classpathDirs, classOutputDir, bootstrapClasspath, aptProcessors);
 
                 // TODO convention for mapping to original file paths, provide FileInfo out of Inputs instead of Paths,
                 //      automatically relativized?
@@ -119,4 +160,19 @@ public Task resolve(Project project, Config config) {
     protected File getGeneratedClassesDir(TaskContext context) {
         return context.outputPath().toFile();
     }
+
+    private Set<String> maybeAddInReactorAptProcessor(List<Input> reactorProcessors, Set<String> processors) {
+        if (processors.isEmpty()) {
+            return Collections.emptySet();
+        }
+        Set<String> existingProcessors = new HashSet<>(processors);
+        reactorProcessors.forEach(input -> input.getFilesAndHashes().forEach(file -> {
+            try (Stream<String> lines = Files.lines(file.getAbsolutePath())) {
+                lines.forEach(line -> existingProcessors.add(line.trim()));
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+        }));
+       return existingProcessors;
+    }
 }
diff --git a/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/J2clTask.java b/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/J2clTask.java
@@ -42,7 +42,9 @@ public Task resolve(Project project, Config config) {
         List<Input> ownNativeJsSources = Collections.singletonList(input(project, OutputTypes.BYTECODE).filter(NATIVE_JS_SOURCES));
 
         // From our classpath, j2cl is only interested in our compile classpath's bytecode
-        List<Input> classpathHeaders = scope(project.getDependencies(), com.vertispan.j2cl.build.task.Dependency.Scope.COMPILE)
+        List<Input> classpathHeaders = scope(project.getDependencies().stream()
+                .filter(dep -> dep.getProject().getProcessors().isEmpty())
+                .collect(Collectors.toSet()), com.vertispan.j2cl.build.task.Dependency.Scope.COMPILE)
                 .stream()
                 .map(inputs(OutputTypes.STRIPPED_BYTECODE_HEADERS))
                 // we only want bytecode _changes_, but we'll use the whole dir

diff --git a/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/JavacTask.java b/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/JavacTask.java
@@ -9,6 +9,7 @@
 import java.nio.file.Path;
 import java.nio.file.PathMatcher;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -59,7 +60,7 @@ public Task resolve(Project project, Config config) {
             ).collect(Collectors.toUnmodifiableList());
 
             List<File> sourcePaths = ownSources.getParentPaths().stream().map(Path::toFile).collect(Collectors.toUnmodifiableList());
-            Javac javac = new Javac(context, null, sourcePaths, classpathDirs, context.outputPath().toFile(), bootstrapClasspath);
+            Javac javac = new Javac(context, null, sourcePaths, classpathDirs, context.outputPath().toFile(), bootstrapClasspath, Collections.emptySet());
 
             // TODO convention for mapping to original file paths, provide FileInfo out of Inputs instead of Paths,
             //      automatically relativized?

diff --git a/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/TurbineTask.java b/j2cl-tasks/src/main/java/com/vertispan/j2cl/build/provided/TurbineTask.java
@@ -52,7 +52,10 @@ public Task resolve(Project project, Config config) {
 
         List<File> extraClasspath = config.getExtraClasspath();
 
-        List<Input> compileClasspath = scope(project.getDependencies(), Dependency.Scope.COMPILE).stream()
+        List<Input> compileClasspath = scope(project.getDependencies().stream()
+                        .filter(dep -> dep.getProject().getProcessors().isEmpty())
+                        .collect(Collectors.toSet()), Dependency.Scope.COMPILE)
+                .stream()
                 .map(p -> input(p, OutputTypes.STRIPPED_BYTECODE_HEADERS))
                 .map(input -> input.filter(JAVA_BYTECODE))
                 .collect(Collectors.toUnmodifiableList());

diff --git a/j2cl-tasks/src/main/java/com/vertispan/j2cl/tools/Javac.java b/j2cl-tasks/src/main/java/com/vertispan/j2cl/tools/Javac.java
@@ -13,6 +13,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 /**
@@ -33,7 +34,7 @@ public class Javac {
     StandardJavaFileManager fileManager;
     private DiagnosticCollector<JavaFileObject> listener;
 
-    public Javac(BuildLog log, File generatedClassesPath, List<File> sourcePaths, List<File> classpath, File classesDirFile, File bootstrap) throws IOException {
+    public Javac(BuildLog log, File generatedClassesPath, List<File> sourcePaths, List<File> classpath, File classesDirFile, File bootstrap, Set<String> processors) throws IOException {
         this.log = log;
 //        for (File file : classpath) {
 //            System.out.println(file.getAbsolutePath() + " " + file.exists() + " " + file.isDirectory());
@@ -46,6 +47,11 @@ public Javac(BuildLog log, File generatedClassesPath, List<File> sourcePaths, Li
             //java 9+
             javacOptions.add("--release=8");
         }
+        if (!processors.isEmpty()) {
+            javacOptions.add("-processor");
+            javacOptions.add(String.join(",", processors));
+        }
+
         compiler = ToolProvider.getSystemJavaCompiler();
         listener = new DiagnosticCollector<>();
         fileManager = compiler.getStandardFileManager(listener, null, null);