Helper class to create temp files inside application classpath during the unit tests with Java and jUnit

TempClasspathDirCreator.java

package base;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;

/**
 * Class responsible for creating temporary files inside aplication classpath
 */
public class TempClasspathDirCreator {

    private static final Logger LOGGER = LoggerFactory.getLogger(TempClasspathDirCreator.class);

    private final Class<?> testClass;

    public TempClasspathDirCreator(Object testClassInstance) {
        this.testClass = testClassInstance.getClass();
    }

    /**
     * Creates a temporaty file in the application classpath
     */
    public TempClasspathFile createTempFile(String filename) throws IOException {
        Path classpathDir = new File(
                this.getClass().getProtectionDomain().getCodeSource().getLocation().getPath()
        ).toPath();

        Path testClassDir = classpathDir.resolve(".temp").resolve(testClass.getSimpleName());
        Files.createDirectories(testClassDir);

        Path tempfile = Files.createTempFile(
                testClassDir, filename, ".tmp"
        );  // .temp/testClassName/filename.tmp

        LOGGER.info("Temporary file created in the classpath base directory: " + tempfile);
        return new TempClasspathFile(tempfile, classpathDir);
    }

    public static class TempClasspathFile {

        private final Path filePath;
        private final Path baseDir;

        TempClasspathFile(Path file, Path baseDir) {
            this.filePath = file;
            this.baseDir = baseDir;
        }

        public Path getFilePath() {
            return filePath;
        }

        /**
         * Returns the relative path from the application classpath
         */
        public String getRelativePath() {
            return baseDir.relativize(filePath).toString();
        }

        public void delete() {
            this.filePath.toFile().delete();
        }

        public void write(String content) throws IOException {
            try (FileWriter writer = new FileWriter(filePath.toFile())) {
                writer.write(content);
            }
        }
    }

}