package java8.chapter_01.exercises;
import static org.hamcrest.MatcherAssert.assertThat;
import java.io.File;
import org.hamcrest.Matchers;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;
public class Exercise_03 {
@Rule
public final TemporaryFolder folder = new TemporaryFolder();
@Test
public void findFileWithExtension() throws Exception {
folder.newFile("ignore.txt");
folder.newFile("file.xml");
String suffix = ".xml";
File directory = folder.getRoot();
String[] matchingFiles = listFilesIn(directory, suffix);
assertThat(matchingFiles, Matchers.arrayContaining(Matchers.equalTo("file.xml")));
}
private String[] listFilesIn(File directory, String suffix) {
return directory.list((dir, name) -> name.endsWith(suffix));
}
}