core/src/test/java/org/jclouds/collect/TransformingSetSupplierTest.java

/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds licenses this file
 * to you 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 org.jclouds.collect;

import static org.testng.Assert.assertEquals;

import java.util.List;

import org.testng.annotations.Test;

import com.google.common.base.Function;
import com.google.common.base.Functions;
import com.google.common.base.Suppliers;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Lists;

/**
 * 
 * @author Adrian Cole
 */
@Test(groups = "unit", singleThreaded = true, testName = "TransformingSetSupplierTest")
public class TransformingSetSupplierTest {
   @Test
   public void testTransform() {
      TransformingSetSupplier<String, String> supplier = new TransformingSetSupplier<String, String>(Suppliers
               .<Iterable<String>> ofInstance(ImmutableSet.of("foo")), Functions.forMap(ImmutableMap.of("foo", "bar")));
      assertEquals(supplier.get(), ImmutableSet.<String> of("bar"));
   }

   @Test
   public void testNullsNotReturnedFromSourceSupplier() {
      List<String> ofNull = Lists.newArrayList();
      ofNull.add(null);

      TransformingSetSupplier<String, String> supplier = new TransformingSetSupplier<String, String>(Suppliers
               .<Iterable<String>> ofInstance(ofNull), Functions.forMap(ImmutableMap.of("foo", "bar")));
      assertEquals(supplier.get(), ImmutableSet.<String> of());
   }

   @SuppressWarnings("unchecked")
   @Test
   public void testNullsNotReturnedFromFunction() {
      TransformingSetSupplier<String, String> supplier = new TransformingSetSupplier<String, String>(Suppliers
               .<Iterable<String>> ofInstance(ImmutableSet.of("foo")), (Function) Functions.constant(null));
      assertEquals(supplier.get(), ImmutableSet.<String> of());
   }

}