xref: /libcore/support/src/test/java/tests/util/ForEachRunner.java

/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * 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 tests.util;

/**
 * Runner which executes the provided code under test (via a callback) for each provided input
 * value.
 */
public final class ForEachRunner {

  /**
   * Callback parameterized with a value.
   */
  public interface Callback<T> {
    /**
     * Invokes the callback for the provided value.
     */
    void run(T value) throws Exception;
  }

  private ForEachRunner() {}

  /**
   * Invokes the provided callback for each of the provided named values.
   *
   * @param namesAndValues named values represented as name-value pairs.
   *
   * @param <T> type of value.
   */
  public static <T> void runNamed(Callback<T> callback, Iterable<Pair<String, T>> namesAndValues)
      throws Exception {
    for (Pair<String, T> nameAndValue : namesAndValues) {
      try {
        callback.run(nameAndValue.getSecond());
      } catch (Throwable e) {
        throw new Exception("Failed for " + nameAndValue.getFirst() + ": " + e.getMessage(), e);
      }
    }
  }
}