| 1 | /** |
| 2 | * Licensed to jclouds, Inc. (jclouds) under one or more |
| 3 | * contributor license agreements. See the NOTICE file |
| 4 | * distributed with this work for additional information |
| 5 | * regarding copyright ownership. jclouds licenses this file |
| 6 | * to you under the Apache License, Version 2.0 (the |
| 7 | * "License"); you may not use this file except in compliance |
| 8 | * with the License. You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, |
| 13 | * software distributed under the License is distributed on an |
| 14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| 15 | * KIND, either express or implied. See the License for the |
| 16 | * specific language governing permissions and limitations |
| 17 | * under the License. |
| 18 | */ |
| 19 | package org.jclouds.rest.functions; |
| 20 | |
| 21 | import static com.google.common.base.Preconditions.checkNotNull; |
| 22 | import static org.jclouds.util.Throwables2.propagateOrNull; |
| 23 | |
| 24 | import java.util.Set; |
| 25 | |
| 26 | import javax.inject.Inject; |
| 27 | import javax.inject.Singleton; |
| 28 | |
| 29 | import org.jclouds.http.functions.ReturnTrueOn404; |
| 30 | import org.jclouds.rest.ResourceNotFoundException; |
| 31 | |
| 32 | import com.google.common.base.Function; |
| 33 | import com.google.common.base.Throwables; |
| 34 | import com.google.common.collect.ImmutableSet; |
| 35 | import com.google.common.collect.Iterables; |
| 36 | |
| 37 | /** |
| 38 | * |
| 39 | * @author Adrian Cole |
| 40 | */ |
| 41 | @Singleton |
| 42 | public class ReturnEmptySetOnNotFoundOr404 implements Function<Exception, Object> { |
| 43 | private final ReturnTrueOn404 rto404; |
| 44 | |
| 45 | @Inject |
| 46 | private ReturnEmptySetOnNotFoundOr404(ReturnTrueOn404 rto404) { |
| 47 | this.rto404 = checkNotNull(rto404, "rto404"); |
| 48 | } |
| 49 | |
| 50 | public Object apply(Exception from) { |
| 51 | Iterable<ResourceNotFoundException> throwables = Iterables.filter(Throwables.getCausalChain(from), |
| 52 | ResourceNotFoundException.class); |
| 53 | if (Iterables.size(throwables) >= 1) { |
| 54 | return ImmutableSet.of(); |
| 55 | } else if (rto404.apply(from)) { |
| 56 | return ImmutableSet.of(); |
| 57 | } |
| 58 | return Set.class.cast(propagateOrNull(from)); |
| 59 | } |
| 60 | |
| 61 | } |