fr.brouillard.oss.jgitver.cfg.ResourceConfigurationProvider.java Source code

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Here is the source code for fr.brouillard.oss.jgitver.cfg.ResourceConfigurationProvider.java

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/**
 * Copyright (C) 2016 Matthieu Brouillard [http://oss.brouillard.fr/jgitver-maven-plugin] (matthieu@brouillard.fr)
 *
 * 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 fr.brouillard.oss.jgitver.cfg;

import java.io.Closeable;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;

import com.google.common.io.Resources;

public class ResourceConfigurationProvider implements Closeable {
    private File configurationDirectory;

    public ResourceConfigurationProvider(File directory) {
        configurationDirectory = directory;
    }

    /**
     * Builds a {@link ResourceConfigurationProvider} object by saving the given resource as a "jgitver.config.xml" file
     * inside a newly created directory.
     * 
     * @param configurationResource the resource to read as "jgitver.config.xml" content
     * @return a non null {@link ResourceConfigurationProvider}
     */
    public static ResourceConfigurationProvider fromResource(String configurationResource) {
        File dir = com.google.common.io.Files.createTempDir();
        try {
            File mvn = new File(dir, ".mvn");
            mvn.mkdir();
            File f = new File(mvn, "jgitver.config.xml");
            final FileOutputStream fos = new FileOutputStream(f);
            Resources.copy(ResourceConfigurationProvider.class.getResource(configurationResource), fos);
            fos.close();
            return new ResourceConfigurationProvider(dir);
        } catch (Exception ex) {
            try {
                deleteDirectory(dir);
            } catch (IOException ignore) {
                // cannot do anything
            }
            throw new IllegalStateException(
                    "cannot create configuration directory for resource: " + configurationResource, ex);
        }
    }

    public File getConfigurationDirectory() {
        return configurationDirectory;
    }

    @Override
    public void close() throws IOException {
        deleteDirectory(configurationDirectory);
    }

    private static void deleteDirectory(File fileDir) throws IOException {
        Path directory = fileDir.toPath();
        Files.walkFileTree(directory, new SimpleFileVisitor<Path>() {
            @Override
            public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
                Files.delete(file);
                return FileVisitResult.CONTINUE;
            }

            @Override
            public FileVisitResult postVisitDirectory(Path dir, IOException exc) throws IOException {
                Files.delete(dir);
                return FileVisitResult.CONTINUE;
            }
        });
    }
}