| 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.http.functions; |
| 20 | |
| 21 | import static org.jclouds.http.HttpUtils.releasePayload; |
| 22 | |
| 23 | import java.io.IOException; |
| 24 | import java.io.InputStream; |
| 25 | import java.lang.reflect.Type; |
| 26 | |
| 27 | import javax.annotation.Resource; |
| 28 | import javax.inject.Inject; |
| 29 | import javax.inject.Singleton; |
| 30 | |
| 31 | import org.jclouds.http.HttpResponse; |
| 32 | import org.jclouds.http.HttpResponseException; |
| 33 | import org.jclouds.json.Json; |
| 34 | import org.jclouds.logging.Logger; |
| 35 | import org.jclouds.util.Strings2; |
| 36 | |
| 37 | import com.google.common.base.Function; |
| 38 | import com.google.inject.TypeLiteral; |
| 39 | |
| 40 | /** |
| 41 | * This object will parse the body of an HttpResponse and return the result of |
| 42 | * type <T> back to the caller. |
| 43 | * |
| 44 | * @author Adrian Cole |
| 45 | */ |
| 46 | @Singleton |
| 47 | public class ParseJson<T> implements Function<HttpResponse, T> { |
| 48 | |
| 49 | @Resource |
| 50 | protected Logger logger = Logger.NULL; |
| 51 | protected final Json json; |
| 52 | protected final TypeLiteral<T> type; |
| 53 | |
| 54 | @Inject |
| 55 | public ParseJson(Json json, TypeLiteral<T> type) { |
| 56 | this.json = json; |
| 57 | this.type = type; |
| 58 | } |
| 59 | |
| 60 | /** |
| 61 | * parses the http response body to create a new {@code <T>}. |
| 62 | */ |
| 63 | public T apply(HttpResponse from) { |
| 64 | InputStream gson = from.getPayload().getInput(); |
| 65 | try { |
| 66 | return apply(gson); |
| 67 | } catch (Exception e) { |
| 68 | StringBuilder message = new StringBuilder(); |
| 69 | message.append("Error parsing input"); |
| 70 | logger.error(e, message.toString()); |
| 71 | throw new HttpResponseException(message.toString() + "\n" + from, null, from, e); |
| 72 | } finally { |
| 73 | releasePayload(from); |
| 74 | } |
| 75 | |
| 76 | } |
| 77 | |
| 78 | @SuppressWarnings("unchecked") |
| 79 | public T apply(InputStream stream) throws IOException { |
| 80 | return (T) apply(stream, type.getType()); |
| 81 | } |
| 82 | |
| 83 | @SuppressWarnings("unchecked") |
| 84 | public <V> V apply(InputStream stream, Type type) throws IOException { |
| 85 | try { |
| 86 | return (V) json.fromJson(Strings2.toStringAndClose(stream), type); |
| 87 | } finally { |
| 88 | if (stream != null) |
| 89 | stream.close(); |
| 90 | } |
| 91 | } |
| 92 | } |