com.google.devtools.j2objc.AnnotationPreProcessor.java Source code

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Here is the source code for com.google.devtools.j2objc.AnnotationPreProcessor.java

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/*
 * 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.j2objc;

import com.google.common.base.Joiner;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.devtools.j2objc.file.RegularInputFile;
import com.google.devtools.j2objc.util.ErrorUtil;
import com.google.devtools.j2objc.util.FileUtil;
import com.google.devtools.j2objc.util.PathClassLoader;

import org.eclipse.jdt.internal.compiler.impl.CompilerOptions;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.ServiceLoader;

import javax.annotation.processing.Processor;

/**
 * Preprocesses all input with annotation processors, if any,
 * and adds any .java files generated by those annotation processors
 * to the given GenerationBatch.
 */
class AnnotationPreProcessor {

    private File tmpDirectory;
    private GenerationBatch batch;

    AnnotationPreProcessor(GenerationBatch batch) {
        this.batch = batch;
    }

    File getTemporaryDirectory() {
        return tmpDirectory;
    }

    /**
     * Process the given input files, given in the same format as J2ObjC command line args.
     */
    void process(Iterable<String> fileArgs) {
        assert tmpDirectory == null; // Shouldn't run an instance more than once.

        if (!hasAnnotationProcessors()) {
            return;
        }

        try {
            tmpDirectory = FileUtil.createTempDir("annotations");
        } catch (IOException e) {
            ErrorUtil.error("failed creating temporary directory: " + e);
            return;
        }
        String tmpDirPath = tmpDirectory.getAbsolutePath();
        List<String> compileArgs = Lists.newArrayList();
        Joiner pathJoiner = Joiner.on(":");
        List<String> sourcePath = Options.getSourcePathEntries();
        sourcePath.add(tmpDirPath);
        compileArgs.add("-sourcepath");
        compileArgs.add(pathJoiner.join(sourcePath));
        compileArgs.add("-classpath");
        List<String> classPath = Options.getClassPathEntries();
        compileArgs.add(pathJoiner.join(classPath));
        compileArgs.add("-encoding");
        compileArgs.add(Options.getCharset().name());
        compileArgs.add("-source");
        compileArgs.add("1.7");
        compileArgs.add("-s");
        compileArgs.add(tmpDirPath);
        compileArgs.add("-d");
        compileArgs.add(tmpDirPath);
        if (Options.isVerbose()) {
            compileArgs.add("-XprintProcessorInfo");
            compileArgs.add("-XprintRounds");
        }
        for (String fileArg : fileArgs) {
            compileArgs.add(fileArg);
        }
        Map<String, String> batchOptions = Maps.newHashMap();
        batchOptions.put(CompilerOptions.OPTION_Process_Annotations, CompilerOptions.ENABLED);
        batchOptions.put(CompilerOptions.OPTION_GenerateClassFiles, CompilerOptions.DISABLED);
        // Fully qualified name used since "Main" isn't unique.
        org.eclipse.jdt.internal.compiler.batch.Main batchCompiler = new org.eclipse.jdt.internal.compiler.batch.Main(
                new PrintWriter(System.out), new PrintWriter(System.err), false, batchOptions, null);
        if (!batchCompiler.compile(compileArgs.toArray(new String[0]))) {
            // Any compilation errors will already by displayed.
            ErrorUtil.error("failed batch processing sources");
        } else {
            addGeneratedSources(tmpDirectory, "");
        }
    }

    /**
     * Check whether any javax.annotation.processing.Processor services are defined on
     * the declared classpath. This is checked here to avoid batch compiling sources
     * in case any might have annotations that should be processed.
     */
    private boolean hasAnnotationProcessors() {
        ServiceLoader<Processor> serviceLoader = ServiceLoader.load(Processor.class,
                new PathClassLoader(Options.getClassPathEntries()));
        Iterator<Processor> iterator = serviceLoader.iterator();
        return iterator.hasNext();
    }

    private void addGeneratedSources(File dir, String currentRelativePath) {
        assert dir.exists() && dir.isDirectory();
        for (File f : dir.listFiles()) {
            String relativeName = currentRelativePath + File.separatorChar + f.getName();
            if (f.isDirectory()) {
                addGeneratedSources(f, relativeName);
            } else {
                if (f.getName().endsWith(".java")) {
                    batch.addSource(new RegularInputFile(f.getPath(), relativeName));
                }
            }
        }
    }
}