/*
    * Copyright (C) 2008 The Guava Authors
    *
    * 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 com.google.common.util.concurrent;
  
  import com.google.common.base.Function;
  
  import java.lang.reflect.UndeclaredThrowableException;
  
  /**
   * Unit tests for {@link Futures#transform(ListenableFuture, Function)}.
   *
   * @author Nishant Thakkar
   */
  public class FuturesTransformTest
      extends AbstractChainedListenableFutureTest<String> {
    private static final String RESULT_DATA = "SUCCESS";
  
    @Override protected ListenableFuture<String> buildChainingFuture(
        ListenableFuture<Integer> inputFuture) {
      return Futures.transform(inputFuture,
          new ComposeFunction());
    }
  
    @Override protected String getSuccessfulResult() {
      return RESULT_DATA;
    }
  
    private class ComposeFunction
        implements Function<Integer, String> {
      @Override
      public String apply(Integer input) {
        if (input.intValue() == VALID_INPUT_DATA) {
          return RESULT_DATA;
        } else {
          throw new UndeclaredThrowableException(EXCEPTION);
        }
      }
    }
  
    public void testFutureGetThrowsFunctionException() throws Exception {
      inputFuture.set(EXCEPTION_DATA);
      listener.assertException(EXCEPTION);
    }
  }