third_party/robolectric/template_processor/src/org/chromium/testing/robolectric/template/ProcessRobolectricTemplate.java

// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package org.chromium.testing.robolectric.template;

import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.exception.VelocityException;
import org.apache.velocity.runtime.RuntimeConstants;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.StringWriter;
import java.nio.file.PathMatcher;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.FileSystems;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.util.ArrayList;
import java.util.List;

/**
 * Class to process Robolectric template (*.vm) files using Apache Velocity.
 */
public final class ProcessRobolectricTemplate {

    private ProcessRobolectricTemplate() {
    }

    public static void main(String[] args) {
        final ProcessTemplateArgParser parser = ProcessTemplateArgParser.parse(args);

        Velocity.setProperty(RuntimeConstants.RESOURCE_LOADER, "file");
        Velocity.setProperty(RuntimeConstants.FILE_RESOURCE_LOADER_PATH,
                parser.getBaseTemplateDir().toString());
        Velocity.init();

        final VelocityContext context = new VelocityContext();
        final int api = parser.getApiLevel();
        context.put("api", api);
        if (api >= 21) {
            context.put("ptrClass", "long");
            context.put("ptrClassBoxed", "Long");
        } else {
            context.put("ptrClass", "int");
            context.put("ptrClassBoxed", "Integer");
        }
        try {
            for(TemplateFileInfo templateFileInfo: parser.getTemplateFileInfoList()) {
                processTemplate(context, templateFileInfo.getTemplateFile(),
                        templateFileInfo.getOutputFile(), api);
            }
        } catch (IOException e) {
            System.err.println("Error processing template files for Robolectric! " + e.toString());
        }
    }

    private static void processTemplate(VelocityContext context, Path templateFile,
            Path outputFile, int api_level) throws IOException {
        final StringWriter stringWriter = new StringWriter();
        Template template = Velocity.getTemplate(templateFile.toString(), "UTF-8");
        template.merge(context, stringWriter);
        if (!Files.exists(outputFile.getParent())) {
            Files.createDirectories(outputFile.getParent());
        }
        Files.write(outputFile, stringWriter.toString().getBytes("UTF-8"));
    }
}