*
 * <p>{@link java.nio.file.Path} users will find similar utilities in {@link MoreFiles} and the
 * JDK's {@link java.nio.file.Files} class.
 *
 * @author Chris Nokleberg
 * @author Colin Decker
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class Files {

  private Files() {}

  /**

/**
 * Unit test for {@link Files#createTempDir}.
 *
 * @author Chris Nokleberg
 */

@SuppressWarnings("deprecation") // tests of a deprecated method
public class FilesCreateTempDirTest extends TestCase {
  public void testCreateTempDir() throws IOException {
    if (JAVA_IO_TMPDIR.value().equals("/sdcard")) {
      assertThrows(IllegalStateException.class, Files::createTempDir);
      return;
    }

    util.concurrent tests under Guava.

    The problem is that GWT responds poorly to two .gwt.xml files in the same
    Java package; see https://goo.gl/pRV3Yn for details.

    The summary is that it ignores one file in favor of the other.
    util.concurrent, like nearly all our packages, has two .gwt.xml files: one
    for prod and one for tests. However, unlike our other packages, as of this

    assertEquals("gz", Files.getFileExtension("blah.tar.gz"));
    assertEquals("", Files.getFileExtension("/"));
    assertEquals("", Files.getFileExtension("."));
    assertEquals("", Files.getFileExtension(".."));
    assertEquals("", Files.getFileExtension("..."));
    assertEquals("", Files.getFileExtension("blah"));
    assertEquals("", Files.getFileExtension("blah."));
    assertEquals("", Files.getFileExtension(".blah."));

     has good test coverage, so look at some existing tests if you're unsure
     how to go about it.
  2. All contributions must be licensed Apache 2.0 and all files must have a
     copy of the boilerplate license comment (can be copied from an existing
     file).
  3. Files should be formatted according to Google's [Java style guide][].
  4. Please squash all commits for a change into a single commit (this can be

    assertEquals("gz", Files.getFileExtension("blah.tar.gz"));
    assertEquals("", Files.getFileExtension("/"));
    assertEquals("", Files.getFileExtension("."));
    assertEquals("", Files.getFileExtension(".."));
    assertEquals("", Files.getFileExtension("..."));
    assertEquals("", Files.getFileExtension("blah"));
    assertEquals("", Files.getFileExtension("blah."));
    assertEquals("", Files.getFileExtension(".blah."));

                .build());
    Files.createDirectories(fs.getPath("dir/b/i/j/l"));
    Files.createFile(fs.getPath("dir/a"));
    Files.createFile(fs.getPath("dir/c"));
    Files.createSymbolicLink(fs.getPath("dir/d"), fs.getPath("b/i"));
    Files.createDirectory(fs.getPath("dir/e"));
    Files.createSymbolicLink(fs.getPath("dir/f"), fs.getPath("/dontdelete"));
    Files.createFile(fs.getPath("dir/b/g"));

import com.google.common.base.Preconditions;
import java.io.File;
import java.io.FilenameFilter;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

/**
 * File name filter that only accepts files matching a regular expression. This class is thread-safe
 * and immutable.
 *
 * @author Apple Chow
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault

/**
 * Unit test for {@link Files#createTempDir}.
 *
 * @author Chris Nokleberg
 */

@SuppressWarnings("deprecation") // tests of a deprecated method
public class FilesCreateTempDirTest extends TestCase {
  public void testCreateTempDir() throws IOException {
    if (JAVA_IO_TMPDIR.value().equals("/sdcard")) {
      assertThrows(IllegalStateException.class, Files::createTempDir);
      return;
    }

import java.io.IOException;

/**
 * Tests for {@link Files#fileTraverser()}.
 *
 * @author Jens Nyman
 */

public class FilesFileTraverserTest extends IoTestCase {

  private File rootDir;

  @Override
  public void setUp() throws IOException {
    rootDir = createTempDir();
  }

  public void testFileTraverser_emptyDirectory() throws Exception {