// Copyright 2015 The Bazel Authors. All rights reserved.
//
// 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.google.devtools.build.android.idlclass;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import com.google.devtools.build.buildjar.jarhelper.JarCreator;
import com.google.devtools.build.buildjar.proto.JavaCompilation.CompilationUnit;
import com.google.devtools.build.buildjar.proto.JavaCompilation.Manifest;
import com.google.devtools.common.options.OptionsParser;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Enumeration;
import java.util.List;
import java.util.Set;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
/**
* IdlClass post-processes the output of a Java compilation, and produces
* a jar containing only the class files for sources that were generated
* from idl processing.
*/
public class IdlClass {
public static void main(String[] args) throws IOException {
OptionsParser optionsParser = OptionsParser.newOptionsParser(IdlClassOptions.class);
optionsParser.parseAndExitUponError(args);
IdlClassOptions options = optionsParser.getOptions(IdlClassOptions.class);
Preconditions.checkNotNull(options.manifestProto);
Preconditions.checkNotNull(options.classJar);
Preconditions.checkNotNull(options.outputClassJar);
Preconditions.checkNotNull(options.outputSourceJar);
Preconditions.checkNotNull(options.tempDir);
List<Path> idlSources = Lists.newArrayList();
for (String idlSource : optionsParser.getResidue()) {
idlSources.add(Paths.get(idlSource));
}
Manifest manifest = readManifest(options.manifestProto);
writeClassJar(options, idlSources, manifest);
writeSourceJar(options, idlSources, manifest);
}
private static void writeClassJar(IdlClassOptions options,
List<Path> idlSources, Manifest manifest) throws IOException {
Path tempDir = options.tempDir.resolve("classjar");
Set<Path> idlSourceSet = Sets.newHashSet(idlSources);
extractIdlClasses(options.classJar, manifest, tempDir, idlSourceSet);
writeOutputJar(options.outputClassJar, tempDir);
}
private static void writeSourceJar(IdlClassOptions options,
List<Path> idlSources, Manifest manifest) throws IOException {
Path tempDir = options.tempDir.resolve("sourcejar");
Path idlSourceBaseDir = options.idlSourceBaseDir;
for (Path path : idlSources) {
for (CompilationUnit unit : manifest.getCompilationUnitList()) {
if (Paths.get(unit.getPath()).equals(path)) {
String pkg = unit.getPkg();
Path source = idlSourceBaseDir != null ? idlSourceBaseDir.resolve(path) : path;
Path target = tempDir.resolve(pkg.replace('.', '/')).resolve(path.getFileName());
Files.createDirectories(target.getParent());
Files.copy(source, target);
break;
}
}
}
writeOutputJar(options.outputSourceJar, tempDir);
}
/**
* Reads the compilation manifest.
*/
private static Manifest readManifest(Path path) throws IOException {
Manifest manifest;
try (InputStream inputStream = Files.newInputStream(path)) {
manifest = Manifest.parseFrom(inputStream);
}
return manifest;
}
/**
* For each top-level class in the compilation, determine the path prefix of classes corresponding
* to that compilation unit.
*
* <p>Prefixes are used to correctly handle inner classes, e.g. the top-level class "c.g.Foo" may
* correspond to "c/g/Foo.class" and also "c/g/Foo$Inner.class" or "c/g/Foo$0.class".
*/
@VisibleForTesting
static ImmutableSet<String> getIdlPrefixes(Manifest manifest, Set<Path> idlSources) {
ImmutableSet.Builder<String> prefixes = ImmutableSet.builder();
for (CompilationUnit unit : manifest.getCompilationUnitList()) {
if (!idlSources.contains(Paths.get(unit.getPath()))) {
continue;
}
String pkg;
if (unit.hasPkg()) {
pkg = unit.getPkg().replace('.', '/') + "/";
} else {
pkg = "";
}
for (String toplevel : unit.getTopLevelList()) {
prefixes.add(pkg + toplevel);
}
}
return prefixes.build();
}
/**
* Unzip all the class files that correspond to idl processor- generated sources into the
* temporary directory.
*/
private static void extractIdlClasses(
Path classJar, Manifest manifest, Path tempDir, Set<Path> idlSources) throws IOException {
ImmutableSet<String> prefixes = getIdlPrefixes(manifest, idlSources);
try (JarFile jar = new JarFile(classJar.toFile())) {
Enumeration<JarEntry> entries = jar.entries();
while (entries.hasMoreElements()) {
JarEntry entry = entries.nextElement();
String name = entry.getName();
if (!name.endsWith(".class")) {
continue;
}
String prefix = name.substring(0, name.length() - ".class".length());
int idx = prefix.indexOf('$');
if (idx > 0) {
prefix = prefix.substring(0, idx);
}
if (prefixes.contains(prefix)) {
Files.createDirectories(tempDir.resolve(name).getParent());
Files.copy(jar.getInputStream(entry), tempDir.resolve(name));
}
}
}
}
/** Writes the generated class files to the output jar. */
private static void writeOutputJar(Path outputJar, Path tempDir) throws IOException {
JarCreator output = new JarCreator(outputJar.toString());
output.setCompression(true);
output.setNormalize(true);
output.addDirectory(tempDir.toString());
output.execute();
}
}