Java tutorial
/* * * Copyright 2013 Netflix, Inc. * * 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.netflix.ice.basic; import com.amazonaws.services.s3.AmazonS3Client; import com.amazonaws.services.s3.model.ObjectMetadata; import com.google.common.collect.Maps; import com.netflix.ice.common.AwsUtils; import com.netflix.ice.reader.ApplicationGroup; import com.netflix.ice.reader.ApplicationGroupService; import com.netflix.ice.reader.ReaderConfig; import org.apache.commons.io.IOUtils; import org.json.JSONException; import org.json.JSONObject; import org.json.JSONTokener; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.ByteArrayInputStream; import java.io.InputStream; import java.util.Iterator; import java.util.Map; public class BasicS3ApplicationGroupService implements ApplicationGroupService { private final static Logger logger = LoggerFactory.getLogger(BasicS3ApplicationGroupService.class); private AmazonS3Client s3Client; private ReaderConfig config; public void init() { this.config = ReaderConfig.getInstance(); s3Client = AwsUtils.getAmazonS3Client(); } private String getJson(Map<String, ApplicationGroup> appgroups) throws JSONException { JSONObject json = new JSONObject(); for (String name : appgroups.keySet()) { ApplicationGroup appgroup = appgroups.get(name); json.put(name, appgroup.getJSON()); } return json.toString(); } public Map<String, ApplicationGroup> getApplicationGroups() { String jsonStr; try { InputStream in = s3Client.getObject(config.workS3BucketName, config.workS3BucketPrefix + "appgroups") .getObjectContent(); jsonStr = IOUtils.toString(in); in.close(); } catch (Exception e) { logger.error("Error reading from appgroups file", e); try { InputStream in = s3Client .getObject(config.workS3BucketName, config.workS3BucketPrefix + "copy_appgroups") .getObjectContent(); jsonStr = IOUtils.toString(in); in.close(); } catch (Exception r) { logger.error("Error reading from copy_appgroups file", r); return Maps.newHashMap(); } } try { JSONObject json = new JSONObject(new JSONTokener(jsonStr)); Map<String, ApplicationGroup> appgroups = Maps.newHashMap(); Iterator<String> keys = json.keys(); while (keys.hasNext()) { String key = keys.next(); String str = json.getString(key); appgroups.put(key, new ApplicationGroup(str)); } return appgroups; } catch (JSONException e) { logger.error("Error reading appgroups from json...", e); return Maps.newHashMap(); } } public ApplicationGroup getApplicationGroup(String name) { Map<String, ApplicationGroup> appgroups = getApplicationGroups(); return appgroups.get(name); } public boolean saveApplicationGroup(ApplicationGroup appgroup) { Map<String, ApplicationGroup> appgroups = getApplicationGroups(); appgroups.put(appgroup.name, appgroup); try { String json = getJson(appgroups); s3Client.putObject(config.workS3BucketName, config.workS3BucketPrefix + "appgroups", IOUtils.toInputStream(json), new ObjectMetadata()); s3Client.putObject(config.workS3BucketName, config.workS3BucketPrefix + "copy_appgroups", IOUtils.toInputStream(json), new ObjectMetadata()); BasicS3ApplicationGroupService.logger.info("saved appgroup " + appgroup); return true; } catch (JSONException e) { logger.error("Error saving appgroup " + appgroup, e); return false; } } public boolean deleteApplicationGroup(String name) { Map<String, ApplicationGroup> appgroups = getApplicationGroups(); ApplicationGroup appgroup = appgroups.remove(name); try { String json = getJson(appgroups); s3Client.putObject(config.workS3BucketName, config.workS3BucketPrefix + "appgroups", new ByteArrayInputStream(json.getBytes()), new ObjectMetadata()); BasicS3ApplicationGroupService.logger.info("delete appgroup " + name + " " + appgroup); return true; } catch (JSONException e) { logger.error("Error deleting appgroup " + appgroup, e); return false; } } }