@ElementTypesAreNonnullByDefault
public abstract class Traverser<N> {
  private final SuccessorsFunction<N> successorFunction;

  private Traverser(SuccessorsFunction<N> successorFunction) {
    this.successorFunction = checkNotNull(successorFunction);
  }

  /**
   * Creates a new traverser for the given general {@code graph}.
   *
   * <p>Traversers created using this method are guaranteed to visit each node reachable from the

@ElementTypesAreNonnullByDefault
public abstract class Traverser<N> {
  private final SuccessorsFunction<N> successorFunction;

  private Traverser(SuccessorsFunction<N> successorFunction) {
    this.successorFunction = checkNotNull(successorFunction);
  }

  /**
   * Creates a new traverser for the given general {@code graph}.
   *
   * <p>Traversers created using this method are guaranteed to visit each node reachable from the

 * governing permissions and limitations under the License.
 */
package org.codelibs.core.io;

/**
 * クラスやリソースの集まりを表すオブジェクトです。
 *
 * @author koichik
 * @see TraversalUtil
 */
public interface Traverser {

    /**
     * 指定されたクラス名に対応するクラスファイルがこのインスタンスが扱うリソースの中に存在すれば<code>true</code>を返します。
     * <p>
     * インスタンス構築時にルートパッケージが指定されている場合、 指定されたクラス名はルートパッケージからの相対名として解釈されます。
     * </p>
     *
     * @param className

        final Traverser[] traversers = TraversalUtil.getTraversers("org.codelibs.core.io.xxx");
        assertThat(traversers, is(notNullValue()));
        assertThat(traversers.length, is(1));

        final Traverser traverser = traversers[0];
        assertThat(traverser instanceof FileSystemTraverser, is(true));

        assertThat(traverser.isExistClass("DummyTest"), is(true));

 * implement it:
 *
 * <pre>{@code
 * // won't work
 * TreeTraverser<NodeType> traverser = node -> node.getChildNodes();
 * }</pre>
 *
 * Instead, you can pass a lambda expression to the {@code using} factory method:
 *
 * <pre>{@code
 * TreeTraverser<NodeType> traverser = TreeTraverser.using(node -> node.getChildNodes());
 * }</pre>
 *
 * @author Louis Wasserman
 * @since 15.0

 * @see URLUtil#toCanonicalProtocol(String)
 * @see ClassTraversalUtil
 * @see ResourceTraversalUtil
 */
public abstract class TraversalUtil {

    /** 空の{@link Traverser}の配列です。 */
    protected static final Traverser[] EMPTY_ARRAY = new Traverser[0];

    private static final Logger logger = Logger.getLogger(TraversalUtil.class);

    /** URLのプロトコルをキー、{@link TraverserFactory}を値とするマッピングです。 */

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_breadthFirst_multiGraph() {
    Traverser<Character> traverser = Traverser.forGraph(MULTI_GRAPH);
    assertEqualCharNodes(traverser.breadthFirst('a'), "abcd");

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_breadthFirst_multiGraph() {
    Traverser<Character> traverser = Traverser.forGraph(MULTI_GRAPH);
    assertEqualCharNodes(traverser.breadthFirst('a'), "abcd");

 * implement it:
 *
 * <pre>{@code
 * // won't work
 * TreeTraverser<NodeType> traverser = node -> node.getChildNodes();
 * }</pre>
 *
 * Instead, you can pass a lambda expression to the {@code using} factory method:
 *
 * <pre>{@code
 * TreeTraverser<NodeType> traverser = TreeTraverser.using(node -> node.getChildNodes());
 * }</pre>
 *
 * @author Louis Wasserman
 * @since 15.0

import com.google.common.graph.Traverser;
import com.google.errorprone.refaster.annotation.AfterTemplate;
import com.google.errorprone.refaster.annotation.BeforeTemplate;
import com.google.errorprone.refaster.annotation.Placeholder;

/**
 * Refaster rules to rewrite usages of {@code com.google.common.collect.TreeTraverser} in terms of
 * {@code com.google.common.graph.Traverser}.
 */
@SuppressWarnings("DefaultPackage")