archetype-common/src/main/java/org/apache/maven/archetype/generator/DefaultFilesetArchetypeGenerator.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.maven.archetype.generator;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.TransformerException;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import groovy.lang.Binding;
import groovy.lang.GroovyShell;
import org.apache.maven.archetype.ArchetypeGenerationRequest;
import org.apache.maven.archetype.common.ArchetypeArtifactManager;
import org.apache.maven.archetype.common.ArchetypeFilesResolver;
import org.apache.maven.archetype.common.Constants;
import org.apache.maven.archetype.common.PomManager;
import org.apache.maven.archetype.exception.ArchetypeGenerationFailure;
import org.apache.maven.archetype.exception.ArchetypeNotConfigured;
import org.apache.maven.archetype.exception.InvalidPackaging;
import org.apache.maven.archetype.exception.OutputFileExists;
import org.apache.maven.archetype.exception.PomFileExists;
import org.apache.maven.archetype.exception.ProjectDirectoryExists;
import org.apache.maven.archetype.exception.UnknownArchetype;
import org.apache.maven.archetype.metadata.AbstractArchetypeDescriptor;
import org.apache.maven.archetype.metadata.ArchetypeDescriptor;
import org.apache.maven.archetype.metadata.FileSet;
import org.apache.maven.archetype.metadata.ModuleDescriptor;
import org.apache.maven.archetype.metadata.RequiredProperty;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.context.Context;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.codehaus.plexus.component.annotations.Component;
import org.codehaus.plexus.component.annotations.Requirement;
import org.codehaus.plexus.logging.AbstractLogEnabled;
import org.codehaus.plexus.util.FileUtils;
import org.codehaus.plexus.util.IOUtil;
import org.codehaus.plexus.util.StringUtils;
import org.codehaus.plexus.util.xml.pull.XmlPullParserException;
import org.codehaus.plexus.velocity.VelocityComponent;
import org.xml.sax.SAXException;

@Component(role = FilesetArchetypeGenerator.class)
public class DefaultFilesetArchetypeGenerator extends AbstractLogEnabled implements FilesetArchetypeGenerator {
    @Requirement
    private ArchetypeArtifactManager archetypeArtifactManager;

    @Requirement
    private ArchetypeFilesResolver archetypeFilesResolver;

    @Requirement
    private PomManager pomManager;

    @Requirement
    private VelocityComponent velocity;

    /**
     * Pattern used to detect tokens in a string. Tokens are any text surrounded
     * by the delimiter <code>__</code>.
     */
    private static final Pattern TOKEN_PATTERN = Pattern.compile("__((?:[^_]+_)*[^_]+)__");

    @Override
    public void generateArchetype(ArchetypeGenerationRequest request, File archetypeFile)
            throws UnknownArchetype, ArchetypeNotConfigured, ProjectDirectoryExists, PomFileExists, OutputFileExists,
                    ArchetypeGenerationFailure, InvalidPackaging {
        ClassLoader old = Thread.currentThread().getContextClassLoader();

        try {
            ArchetypeDescriptor archetypeDescriptor =
                    archetypeArtifactManager.getFileSetArchetypeDescriptor(archetypeFile);

            if (!isArchetypeConfigured(archetypeDescriptor, request)) {
                if (request.isInteractiveMode()) {
                    throw new ArchetypeNotConfigured("No archetype was chosen.", null);
                }

                StringBuilder exceptionMessage = new StringBuilder(
                        "Archetype " + request.getArchetypeGroupId() + ":" + request.getArchetypeArtifactId() + ":"
                                + request.getArchetypeVersion() + " is not configured");

                List<String> missingProperties = new ArrayList<>(0);
                for (RequiredProperty requiredProperty : archetypeDescriptor.getRequiredProperties()) {
                    if (StringUtils.isEmpty(request.getProperties().getProperty(requiredProperty.getKey()))) {
                        exceptionMessage.append("\n\tProperty " + requiredProperty.getKey() + " is missing.");

                        missingProperties.add(requiredProperty.getKey());
                    }
                }

                throw new ArchetypeNotConfigured(exceptionMessage.toString(), missingProperties);
            }

            Context context = prepareVelocityContext(request);

            String packageName = request.getPackage();
            String artifactId = request.getArtifactId();
            File outputDirectoryFile = new File(request.getOutputDirectory(), artifactId);
            File basedirPom = new File(request.getOutputDirectory(), Constants.ARCHETYPE_POM);
            File pom = new File(outputDirectoryFile, Constants.ARCHETYPE_POM);

            List<String> archetypeResources = archetypeArtifactManager.getFilesetArchetypeResources(archetypeFile);

            ZipFile archetypeZipFile = archetypeArtifactManager.getArchetypeZipFile(archetypeFile);

            ClassLoader archetypeJarLoader = archetypeArtifactManager.getArchetypeJarLoader(archetypeFile);

            Thread.currentThread().setContextClassLoader(archetypeJarLoader);

            if (archetypeDescriptor.isPartial()) {
                getLogger().debug("Processing partial archetype " + archetypeDescriptor.getName());
                if (outputDirectoryFile.exists()) {
                    if (!pom.exists()) {
                        throw new PomFileExists("This is a partial archetype and the pom.xml file doesn't exist.");
                    }

                    processPomWithMerge(context, pom, "");

                    processArchetypeTemplatesWithWarning(
                            archetypeDescriptor,
                            archetypeResources,
                            archetypeZipFile,
                            "",
                            context,
                            packageName,
                            outputDirectoryFile);
                } else {
                    if (basedirPom.exists()) {
                        processPomWithMerge(context, basedirPom, "");

                        processArchetypeTemplatesWithWarning(
                                archetypeDescriptor,
                                archetypeResources,
                                archetypeZipFile,
                                "",
                                context,
                                packageName,
                                new File(request.getOutputDirectory()));
                    } else {
                        processPom(context, pom, "");

                        processArchetypeTemplates(
                                archetypeDescriptor,
                                archetypeResources,
                                archetypeZipFile,
                                "",
                                context,
                                packageName,
                                outputDirectoryFile);
                    }
                }

                if (archetypeDescriptor.getModules().size() > 0) {
                    getLogger().info("Modules ignored in partial mode");
                }
            } else {
                getLogger().debug("Processing complete archetype " + archetypeDescriptor.getName());
                if (outputDirectoryFile.exists() && pom.exists()) {
                    throw new ProjectDirectoryExists(
                            "A Maven project already exists in the directory " + outputDirectoryFile.getPath());
                }

                if (outputDirectoryFile.exists()) {
                    getLogger().warn("The directory " + outputDirectoryFile.getPath() + " already exists.");
                }

                context.put("rootArtifactId", artifactId);

                processFilesetModule(
                        artifactId,
                        artifactId,
                        archetypeResources,
                        pom,
                        archetypeZipFile,
                        "",
                        basedirPom,
                        outputDirectoryFile,
                        packageName,
                        archetypeDescriptor,
                        context);
            }

            String postGenerationScript = archetypeArtifactManager.getPostGenerationScript(archetypeFile);
            if (postGenerationScript != null) {
                getLogger().info("Executing " + Constants.ARCHETYPE_POST_GENERATION_SCRIPT + " post-generation script");

                Binding binding = new Binding();

                final Properties archetypeGeneratorProperties = new Properties();
                archetypeGeneratorProperties.putAll(System.getProperties());

                if (request.getProperties() != null) {
                    archetypeGeneratorProperties.putAll(request.getProperties());
                }

                for (Map.Entry<Object, Object> entry : archetypeGeneratorProperties.entrySet()) {
                    binding.setVariable(entry.getKey().toString(), entry.getValue());
                }

                binding.setVariable("request", request);

                GroovyShell shell = new GroovyShell(binding);
                shell.evaluate(postGenerationScript);
            }

            // ----------------------------------------------------------------------
            // Log message on OldArchetype creation
            // ----------------------------------------------------------------------
            if (getLogger().isInfoEnabled()) {
                getLogger().info("Project created from Archetype in dir: " + outputDirectoryFile.getAbsolutePath());
            }
        } catch (IOException
                | XmlPullParserException
                | ParserConfigurationException
                | TransformerException
                | SAXException e) {
            throw new ArchetypeGenerationFailure(e);
        } finally {
            Thread.currentThread().setContextClassLoader(old);
        }
    }

    public String getPackageAsDirectory(String packageName) {
        return StringUtils.replace(packageName, ".", "/");
    }

    private boolean copyFile(
            final File outFile, final String template, final boolean failIfExists, final ZipFile archetypeZipFile)
            throws OutputFileExists, IOException {
        getLogger().debug("Copying file " + template);

        if (failIfExists && outFile.exists()) {
            throw new OutputFileExists("Don't rewrite file " + outFile.getName());
        } else if (outFile.exists()) {
            getLogger().warn("CP Don't override file " + outFile);

            return false;
        }

        ZipEntry input = archetypeZipFile.getEntry(Constants.ARCHETYPE_RESOURCES + "/" + template);

        if (input.isDirectory()) {
            outFile.mkdirs();
        } else {
            outFile.getParentFile().mkdirs();
            if (!outFile.exists() && !outFile.createNewFile()) {
                getLogger().warn("Could not create new file \"" + outFile.getPath() + "\" or the file already exists.");
            }

            try (InputStream inputStream = archetypeZipFile.getInputStream(input);
                    OutputStream out = new FileOutputStream(outFile)) {
                IOUtil.copy(inputStream, out);
            }
        }

        return true;
    }

    private int copyFiles(
            String directory,
            List<String> fileSetResources,
            boolean packaged,
            String packageName,
            File outputDirectoryFile,
            ZipFile archetypeZipFile,
            String moduleOffset,
            boolean failIfExists,
            Context context)
            throws OutputFileExists, FileNotFoundException, IOException {
        int count = 0;

        for (String template : fileSetResources) {
            File outputFile = getOutputFile(
                    template, directory, outputDirectoryFile, packaged, packageName, moduleOffset, context);

            if (copyFile(outputFile, template, failIfExists, archetypeZipFile)) {
                count++;
            }
        }

        return count;
    }

    private String getEncoding(String archetypeEncoding) {
        return (archetypeEncoding == null || archetypeEncoding.isEmpty()) ? "UTF-8" : archetypeEncoding;
    }

    private String getOffsetSeparator(String moduleOffset) {
        return (moduleOffset == null || moduleOffset.isEmpty()) ? "/" : ("/" + moduleOffset + "/");
    }

    private File getOutputFile(
            String template,
            String directory,
            File outputDirectoryFile,
            boolean packaged,
            String packageName,
            String moduleOffset,
            Context context) {
        String templateName = StringUtils.replaceOnce(template, directory, "");

        String outputFileName = directory + "/" + (packaged ? getPackageAsDirectory(packageName) : "") + "/"
                + templateName.substring(moduleOffset.length());

        outputFileName = replaceFilenameTokens(outputFileName, context);

        return new File(outputDirectoryFile, outputFileName);
    }

    /**
     * Replaces all tokens (text matching {@link #TOKEN_PATTERN}) within
     * the given string, using properties contained within the context. If a
     * property does not exist in the context, the token is left unmodified
     * and a warning is logged.
     *
     * @param filePath the file name and path to be interpolated
     * @param context  contains the available properties
     */
    private String replaceFilenameTokens(final String filePath, final Context context) {
        StringBuffer interpolatedResult = new StringBuffer();
        Matcher matcher = TOKEN_PATTERN.matcher(filePath);

        while (matcher.find()) {
            String propertyToken = matcher.group(1);
            String contextPropertyValue = (String) context.get(propertyToken);
            if (contextPropertyValue != null && contextPropertyValue.trim().length() > 0) {
                if (getLogger().isDebugEnabled()) {
                    getLogger()
                            .debug("Replacing property '" + propertyToken + "' in file path '" + filePath
                                    + "' with value '" + contextPropertyValue + "'.");
                }
                matcher.appendReplacement(interpolatedResult, contextPropertyValue);
            } else {
                // Need to skip the undefined property
                getLogger()
                        .warn("Property '" + propertyToken + "' was not specified, so the token in '" + filePath
                                + "' is not being replaced.");
            }
        }

        matcher.appendTail(interpolatedResult);

        if (getLogger().isDebugEnabled()) {
            getLogger().debug("Final interpolated file path: '" + interpolatedResult + "'");
        }

        return interpolatedResult.toString();
    }

    private String getPackageInPathFormat(String aPackage) {
        return StringUtils.replace(aPackage, ".", "/");
    }

    private boolean isArchetypeConfigured(ArchetypeDescriptor archetypeDescriptor, ArchetypeGenerationRequest request) {
        for (RequiredProperty requiredProperty : archetypeDescriptor.getRequiredProperties()) {
            if (StringUtils.isEmpty(request.getProperties().getProperty(requiredProperty.getKey()))) {
                return false;
            }
        }

        return true;
    }

    private void setParentArtifactId(Context context, String artifactId) {
        context.put(Constants.PARENT_ARTIFACT_ID, artifactId);
    }

    private Context prepareVelocityContext(ArchetypeGenerationRequest request) {
        Context context = new VelocityContext();
        context.put(Constants.GROUP_ID, request.getGroupId());
        context.put(Constants.ARTIFACT_ID, request.getArtifactId());
        context.put(Constants.VERSION, request.getVersion());
        context.put(Constants.PACKAGE, request.getPackage());
        final String packageInPathFormat = getPackageInPathFormat(request.getPackage());
        context.put(Constants.PACKAGE_IN_PATH_FORMAT, packageInPathFormat);

        if (getLogger().isInfoEnabled()) {
            getLogger().info("----------------------------------------------------------------------------");

            getLogger()
                    .info("Using following parameters for creating project from Archetype: "
                            + request.getArchetypeArtifactId() + ":" + request.getArchetypeVersion());

            getLogger().info("----------------------------------------------------------------------------");
            getLogger().info("Parameter: " + Constants.GROUP_ID + ", Value: " + request.getGroupId());
            getLogger().info("Parameter: " + Constants.ARTIFACT_ID + ", Value: " + request.getArtifactId());
            getLogger().info("Parameter: " + Constants.VERSION + ", Value: " + request.getVersion());
            getLogger().info("Parameter: " + Constants.PACKAGE + ", Value: " + request.getPackage());
            getLogger().info("Parameter: " + Constants.PACKAGE_IN_PATH_FORMAT + ", Value: " + packageInPathFormat);
        }

        for (Iterator<?> iterator = request.getProperties().keySet().iterator(); iterator.hasNext(); ) {
            String key = (String) iterator.next();

            String value = request.getProperties().getProperty(key);

            if (maybeVelocityExpression(value)) {
                value = evaluateExpression(context, key, value);
            }

            context.put(key, value);

            if (getLogger().isInfoEnabled()) {
                getLogger().info("Parameter: " + key + ", Value: " + value);
            }
        }
        return context;
    }

    private boolean maybeVelocityExpression(String value) {
        return value != null && value.contains("${");
    }

    private String evaluateExpression(Context context, String key, String value) {
        try (StringWriter stringWriter = new StringWriter()) {
            Velocity.evaluate(context, stringWriter, key, value);
            return stringWriter.toString();
        } catch (Exception ex) {
            return value;
        }
    }

    private void processArchetypeTemplates(
            AbstractArchetypeDescriptor archetypeDescriptor,
            List<String> archetypeResources,
            ZipFile archetypeZipFile,
            String moduleOffset,
            Context context,
            String packageName,
            File outputDirectoryFile)
            throws OutputFileExists, ArchetypeGenerationFailure, FileNotFoundException, IOException {
        processTemplates(
                packageName,
                outputDirectoryFile,
                context,
                archetypeDescriptor,
                archetypeResources,
                archetypeZipFile,
                moduleOffset,
                false);
    }

    private void processArchetypeTemplatesWithWarning(
            ArchetypeDescriptor archetypeDescriptor,
            List<String> archetypeResources,
            ZipFile archetypeZipFile,
            String moduleOffset,
            Context context,
            String packageName,
            File outputDirectoryFile)
            throws OutputFileExists, ArchetypeGenerationFailure, FileNotFoundException, IOException {
        processTemplates(
                packageName,
                outputDirectoryFile,
                context,
                archetypeDescriptor,
                archetypeResources,
                archetypeZipFile,
                moduleOffset,
                true);
    }

    private int processFileSet(
            String directory,
            List<String> fileSetResources,
            boolean packaged,
            String packageName,
            Context context,
            File outputDirectoryFile,
            String moduleOffset,
            String archetypeEncoding,
            boolean failIfExists)
            throws IOException, OutputFileExists, ArchetypeGenerationFailure {
        int count = 0;

        for (String template : fileSetResources) {
            File outputFile = getOutputFile(
                    template, directory, outputDirectoryFile, packaged, packageName, moduleOffset, context);

            if (processTemplate(
                    outputFile,
                    context,
                    Constants.ARCHETYPE_RESOURCES + "/" + template,
                    archetypeEncoding,
                    failIfExists)) {
                count++;
            }
        }

        return count;
    }

    private void processFilesetModule(
            final String rootArtifactId,
            final String artifactId,
            final List<String> archetypeResources,
            File pom,
            final ZipFile archetypeZipFile,
            String moduleOffset,
            File basedirPom,
            File outputDirectoryFile,
            final String packageName,
            final AbstractArchetypeDescriptor archetypeDescriptor,
            final Context context)
            throws XmlPullParserException, IOException, ParserConfigurationException, SAXException,
                    TransformerException, OutputFileExists, ArchetypeGenerationFailure, InvalidPackaging {
        outputDirectoryFile.mkdirs();
        getLogger().debug("Processing module " + artifactId);
        getLogger().debug("Processing module rootArtifactId " + rootArtifactId);
        getLogger().debug("Processing module pom " + pom);
        getLogger().debug("Processing module moduleOffset " + moduleOffset);
        getLogger().debug("Processing module outputDirectoryFile " + outputDirectoryFile);

        processFilesetProject(
                archetypeDescriptor,
                StringUtils.replace(artifactId, "${rootArtifactId}", rootArtifactId),
                archetypeResources,
                pom,
                archetypeZipFile,
                moduleOffset,
                context,
                packageName,
                outputDirectoryFile,
                basedirPom);

        String parentArtifactId = (String) context.get(Constants.PARENT_ARTIFACT_ID);

        Iterator<ModuleDescriptor> subprojects =
                archetypeDescriptor.getModules().iterator();

        if (subprojects.hasNext()) {
            getLogger().debug(artifactId + " has modules (" + archetypeDescriptor.getModules() + ")");

            setParentArtifactId(context, StringUtils.replace(artifactId, "${rootArtifactId}", rootArtifactId));
        }

        while (subprojects.hasNext()) {
            ModuleDescriptor project = subprojects.next();

            String modulePath = StringUtils.replace(project.getDir(), "__rootArtifactId__", rootArtifactId);
            modulePath = replaceFilenameTokens(modulePath, context);

            File moduleOutputDirectoryFile = new File(outputDirectoryFile, modulePath);

            context.put(
                    Constants.ARTIFACT_ID, StringUtils.replace(project.getId(), "${rootArtifactId}", rootArtifactId));

            String moduleArtifactId = StringUtils.replace(project.getDir(), "__rootArtifactId__", rootArtifactId);
            moduleArtifactId = replaceFilenameTokens(moduleArtifactId, context);

            processFilesetModule(
                    rootArtifactId,
                    moduleArtifactId,
                    archetypeResources,
                    new File(moduleOutputDirectoryFile, Constants.ARCHETYPE_POM),
                    archetypeZipFile,
                    ((moduleOffset == null || moduleOffset.isEmpty()) ? "" : (moduleOffset + "/"))
                            + StringUtils.replace(project.getDir(), "${rootArtifactId}", rootArtifactId),
                    pom,
                    moduleOutputDirectoryFile,
                    packageName,
                    project,
                    context);
        }

        restoreParentArtifactId(context, parentArtifactId);

        getLogger().debug("Processed " + artifactId);
    }

    private void processFilesetProject(
            final AbstractArchetypeDescriptor archetypeDescriptor,
            final String moduleId,
            final List<String> archetypeResources,
            final File pom,
            final ZipFile archetypeZipFile,
            String moduleOffset,
            final Context context,
            final String packageName,
            final File outputDirectoryFile,
            final File basedirPom)
            throws XmlPullParserException, IOException, ParserConfigurationException, SAXException,
                    TransformerException, OutputFileExists, ArchetypeGenerationFailure, InvalidPackaging {
        getLogger().debug("Processing fileset project moduleId " + moduleId);
        getLogger().debug("Processing fileset project pom " + pom);
        getLogger().debug("Processing fileset project moduleOffset " + moduleOffset);
        getLogger().debug("Processing fileset project outputDirectoryFile " + outputDirectoryFile);
        getLogger().debug("Processing fileset project basedirPom " + basedirPom);

        if (basedirPom.exists()) {
            processPomWithParent(context, pom, moduleOffset, basedirPom, moduleId);
        } else {
            processPom(context, pom, moduleOffset);
        }

        processArchetypeTemplates(
                archetypeDescriptor,
                archetypeResources,
                archetypeZipFile,
                moduleOffset,
                context,
                packageName,
                outputDirectoryFile);
    }

    private void processPom(Context context, File pom, String moduleOffset)
            throws IOException, OutputFileExists, ArchetypeGenerationFailure {
        getLogger().debug("Processing pom " + pom);

        processTemplate(
                pom,
                context,
                Constants.ARCHETYPE_RESOURCES + getOffsetSeparator(moduleOffset) + Constants.ARCHETYPE_POM,
                getEncoding(null),
                true);
    }

    private void processPomWithMerge(Context context, File pom, String moduleOffset)
            throws OutputFileExists, IOException, XmlPullParserException, ArchetypeGenerationFailure {
        getLogger().debug("Processing pom " + pom + " with merge");

        File temporaryPom = getTemporaryFile(pom);

        processTemplate(
                temporaryPom,
                context,
                Constants.ARCHETYPE_RESOURCES + getOffsetSeparator(moduleOffset) + Constants.ARCHETYPE_POM,
                getEncoding(null),
                true);

        pomManager.mergePoms(pom, temporaryPom);

        // getTemporaryFile sets deleteOnExit. Lets try to delete and then make sure deleteOnExit is
        // still set. Windows has issues deleting files with certain JDKs.
        try {
            FileUtils.forceDelete(temporaryPom);
        } catch (IOException e) {
            temporaryPom.deleteOnExit();
        }
    }

    private void processPomWithParent(Context context, File pom, String moduleOffset, File basedirPom, String moduleId)
            throws XmlPullParserException, IOException, ParserConfigurationException, SAXException,
                    TransformerException, OutputFileExists, ArchetypeGenerationFailure, InvalidPackaging {
        getLogger().debug("Processing pom " + pom + " with parent " + basedirPom);

        processTemplate(
                pom,
                context,
                Constants.ARCHETYPE_RESOURCES + getOffsetSeparator(moduleOffset) + Constants.ARCHETYPE_POM,
                getEncoding(null),
                true);

        getLogger().debug("Adding module " + moduleId);

        pomManager.addModule(basedirPom, moduleId);

        pomManager.addParent(pom, basedirPom);
    }

    @SuppressWarnings("deprecation")
    private boolean processTemplate(
            File outFile, Context context, String templateFileName, String encoding, boolean failIfExists)
            throws IOException, OutputFileExists, ArchetypeGenerationFailure {
        templateFileName = templateFileName.replace(File.separatorChar, '/');

        String localTemplateFileName = templateFileName.replace('/', File.separatorChar);
        if (!templateFileName.equals(localTemplateFileName)
                && !templateExists(templateFileName)
                && templateExists(localTemplateFileName)) {
            templateFileName = localTemplateFileName;
        }

        getLogger().debug("Processing template " + templateFileName);

        if (outFile.exists()) {
            if (failIfExists) {
                throw new OutputFileExists("Don't override file " + outFile.getAbsolutePath());
            }

            getLogger().warn("Don't override file " + outFile);

            return false;
        }

        if (templateFileName.endsWith("/")) {
            getLogger().debug("Creating directory " + outFile);

            outFile.mkdirs();

            return true;
        }

        if (!outFile.getParentFile().exists()) {
            outFile.getParentFile().mkdirs();
        }

        if (!outFile.exists() && !outFile.createNewFile()) {
            getLogger().warn("Could not create new file \"" + outFile.getPath() + "\" or the file already exists.");
        }

        getLogger().debug("Merging into " + outFile);

        try (Writer writer = new OutputStreamWriter(new FileOutputStream(outFile), encoding)) {
            StringWriter stringWriter = new StringWriter();

            velocity.getEngine().mergeTemplate(templateFileName, encoding, context, stringWriter);

            writer.write(StringUtils.unifyLineSeparators(stringWriter.toString()));
        } catch (Exception e) {
            throw new ArchetypeGenerationFailure("Error merging velocity templates: " + e.getMessage(), e);
        }

        return true;
    }

    private boolean templateExists(String templateName) {
        try {
            velocity.getEngine().getTemplate(templateName);
            return true;
        } catch (ResourceNotFoundException | ParseErrorException e) {
            return false;
        }
    }

    private void processTemplates(
            String packageName,
            File outputDirectoryFile,
            Context context,
            AbstractArchetypeDescriptor archetypeDescriptor,
            List<String> archetypeResources,
            ZipFile archetypeZipFile,
            String moduleOffset,
            boolean failIfExists)
            throws OutputFileExists, ArchetypeGenerationFailure, IOException {
        Iterator<FileSet> iterator = archetypeDescriptor.getFileSets().iterator();
        if (iterator.hasNext()) {
            getLogger().debug("Processing filesets" + "\n  " + archetypeResources);
        }

        int count = 0;
        while (iterator.hasNext()) {
            FileSet fileSet = iterator.next();
            count++;

            List<String> fileSetResources =
                    archetypeFilesResolver.filterFiles(moduleOffset, fileSet, archetypeResources);

            // This creates an empty directory, even if there is no file to process
            // Fix for ARCHETYPE-57
            getOutputFile(
                            moduleOffset,
                            fileSet.getDirectory(),
                            outputDirectoryFile,
                            fileSet.isPackaged(),
                            packageName,
                            moduleOffset,
                            context)
                    .mkdirs();

            if (fileSet.isFiltered()) {
                getLogger()
                        .debug("    Processing fileset " + fileSet + " -> " + fileSetResources.size() + ":\n      "
                                + fileSetResources);

                int processed = processFileSet(
                        fileSet.getDirectory(),
                        fileSetResources,
                        fileSet.isPackaged(),
                        packageName,
                        context,
                        outputDirectoryFile,
                        moduleOffset,
                        getEncoding(fileSet.getEncoding()),
                        failIfExists);

                getLogger().debug("    Processed " + processed + " files.");
            } else {
                getLogger()
                        .debug("    Copying fileset " + fileSet + " -> " + fileSetResources.size() + ":\n      "
                                + fileSetResources);

                int copied = copyFiles(
                        fileSet.getDirectory(),
                        fileSetResources,
                        fileSet.isPackaged(),
                        packageName,
                        outputDirectoryFile,
                        archetypeZipFile,
                        moduleOffset,
                        failIfExists,
                        context);

                getLogger().debug("    Copied " + copied + " files.");
            }
        }

        getLogger().debug("Processed " + count + " filesets");
    }

    private void restoreParentArtifactId(Context context, String parentArtifactId) {
        if (parentArtifactId == null || parentArtifactId.isEmpty()) {
            context.remove(Constants.PARENT_ARTIFACT_ID);
        } else {
            context.put(Constants.PARENT_ARTIFACT_ID, parentArtifactId);
        }
    }

    private File getTemporaryFile(File file) {
        File tmp = FileUtils.createTempFile(file.getName(), Constants.TMP, file.getParentFile());

        tmp.deleteOnExit();

        return tmp;
    }
}