Java tutorial
/* * Copyright 2010 Nabeel Mukhtar * * 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.github.api.v2.services.impl; import java.io.InputStream; import java.io.InputStreamReader; import java.lang.reflect.Field; import java.lang.reflect.Type; import java.nio.charset.Charset; import java.util.ArrayList; import java.util.List; import com.github.api.v2.schema.Gist; import com.github.api.v2.schema.Issue; import com.github.api.v2.schema.Language; import com.github.api.v2.schema.Repository; import com.github.api.v2.schema.SchemaEntity; import com.github.api.v2.schema.Tree; import com.github.api.v2.services.AsyncResponseHandler; import com.github.api.v2.services.GitHubException; import com.github.api.v2.services.GitHubService; import com.github.api.v2.services.constant.ApplicationConstants; import com.github.api.v2.services.constant.GitHubApiUrls.GitHubApiUrlBuilder; import com.google.gson.FieldNamingPolicy; import com.google.gson.FieldNamingStrategy; import com.google.gson.Gson; import com.google.gson.GsonBuilder; import com.google.gson.JsonDeserializationContext; import com.google.gson.JsonDeserializer; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import com.google.gson.JsonParseException; import com.google.gson.JsonParser; import com.google.gson.reflect.TypeToken; /** * The Class BaseGitHubService. */ public abstract class BaseGitHubService extends GitHubApiGateway implements GitHubService { protected static final Charset UTF_8_CHAR_SET = Charset.forName(ApplicationConstants.CONTENT_ENCODING); /** The parser. */ private final JsonParser parser = new JsonParser(); /** The handlers. */ private List<AsyncResponseHandler<List<? extends SchemaEntity>>> handlers = new ArrayList<AsyncResponseHandler<List<? extends SchemaEntity>>>(); /** * Instantiates a new base git hub service. */ public BaseGitHubService() { // by default we compress contents requestHeaders.put("Accept-Encoding", "gzip, deflate"); } /** * Instantiates a new base git hub service. * * @param apiVersion * the api version */ public BaseGitHubService(String apiVersion) { setApiVersion(apiVersion); } /** * Unmarshall. * * @param typeToken * the type token * @param response * the response * * @return the t */ @SuppressWarnings("unchecked") protected <T> T unmarshall(TypeToken<T> typeToken, JsonElement response) { Gson gson = getGsonBuilder().create(); return (T) gson.fromJson(response, typeToken.getType()); } /** * Notify observers. * * @param response * the response */ protected void notifyObservers(List<? extends SchemaEntity> response) { for (AsyncResponseHandler<List<? extends SchemaEntity>> handler : handlers) { handler.handleResponse(response); } } /* (non-Javadoc) * @see com.google.code.stackexchange.client.query.StackExchangeApiQuery#addResonseHandler(com.google.code.stackexchange.client.AsyncResponseHandler) */ /** * Adds the resonse handler. * * @param handler * the handler */ public void addResonseHandler(AsyncResponseHandler<List<? extends SchemaEntity>> handler) { handlers.add(handler); } /** * Gets the gson builder. * * @return the gson builder */ protected GsonBuilder getGsonBuilder() { GsonBuilder builder = new GsonBuilder(); builder.setDateFormat(ApplicationConstants.DATE_FORMAT); builder.setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES); builder.setFieldNamingStrategy(new FieldNamingStrategy() { @Override public String translateName(Field field) { if (field.getType().equals(Repository.Visibility.class)) { return "private"; } else if (field.getType().equals(Gist.Visibility.class)) { return "public"; } else { return field.getName(); } } }); builder.registerTypeAdapter(Issue.State.class, new JsonDeserializer<Issue.State>() { @Override public Issue.State deserialize(JsonElement arg0, Type arg1, JsonDeserializationContext arg2) throws JsonParseException { return Issue.State.fromValue(arg0.getAsString()); } }); builder.registerTypeAdapter(Repository.Visibility.class, new JsonDeserializer<Repository.Visibility>() { @Override public Repository.Visibility deserialize(JsonElement arg0, Type arg1, JsonDeserializationContext arg2) throws JsonParseException { return (arg0.getAsBoolean()) ? Repository.Visibility.PRIVATE : Repository.Visibility.PUBLIC; } }); builder.registerTypeAdapter(Gist.Visibility.class, new JsonDeserializer<Gist.Visibility>() { @Override public Gist.Visibility deserialize(JsonElement arg0, Type arg1, JsonDeserializationContext arg2) throws JsonParseException { return (arg0.getAsBoolean()) ? Gist.Visibility.PUBLIC : Gist.Visibility.PRIVATE; } }); builder.registerTypeAdapter(Language.class, new JsonDeserializer<Language>() { @Override public Language deserialize(JsonElement arg0, Type arg1, JsonDeserializationContext arg2) throws JsonParseException { return Language.fromValue(arg0.getAsString()); } }); builder.registerTypeAdapter(Tree.Type.class, new JsonDeserializer<Tree.Type>() { @Override public Tree.Type deserialize(JsonElement arg0, Type arg1, JsonDeserializationContext arg2) throws JsonParseException { return Tree.Type.fromValue(arg0.getAsString()); } }); return builder; } /** * Unmarshall. * * @param jsonContent * the json content * * @return the json object */ protected JsonObject unmarshall(InputStream jsonContent) { try { JsonElement element = parser.parse(new InputStreamReader(jsonContent, UTF_8_CHAR_SET)); if (element.isJsonObject()) { return element.getAsJsonObject(); } else { throw new GitHubException("Unknown content found in response." + element); } } catch (Exception e) { throw new GitHubException(e); } finally { closeStream(jsonContent); } } /** * Creates the git hub api url builder. * * @param urlFormat * the url format * * @return the git hub api url builder */ protected GitHubApiUrlBuilder createGitHubApiUrlBuilder(String urlFormat) { return new GitHubApiUrlBuilder(urlFormat); } }