Java tutorial
/** * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com) * * 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.linkedin.pinot.controller.api.resources; import com.google.common.base.Throwables; import com.google.common.collect.BiMap; import com.linkedin.pinot.common.http.MultiGetRequest; import com.linkedin.pinot.common.restlet.resources.SegmentSizeInfo; import com.linkedin.pinot.common.restlet.resources.TableSizeInfo; import java.net.SocketTimeoutException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.concurrent.CompletionService; import java.util.concurrent.ExecutionException; import java.util.concurrent.Executor; import org.apache.commons.httpclient.ConnectTimeoutException; import org.apache.commons.httpclient.ConnectionPoolTimeoutException; import org.apache.commons.httpclient.HttpConnectionManager; import org.apache.commons.httpclient.URI; import org.apache.commons.httpclient.methods.GetMethod; import org.codehaus.jackson.map.ObjectMapper; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Get the size information details from the server. Only the servers returning success are returned by the method * For servers returning errors (http error or otherwise), no entry is created in the return map */ public class ServerTableSizeReader { private static final Logger LOGGER = LoggerFactory.getLogger(ServerTableSizeReader.class); private final Executor executor; private final HttpConnectionManager connectionManager; public ServerTableSizeReader(Executor executor, HttpConnectionManager connectionManager) { this.executor = executor; this.connectionManager = connectionManager; } public Map<String, List<SegmentSizeInfo>> getSizeDetailsFromServers(BiMap<String, String> serverEndPoints, String table, int timeoutMsec) { List<String> serverUrls = new ArrayList<>(serverEndPoints.size()); BiMap<String, String> endpointsToServers = serverEndPoints.inverse(); for (String endpoint : endpointsToServers.keySet()) { String tableSizeUri = "http://" + endpoint + "/table/" + table + "/size"; serverUrls.add(tableSizeUri); } MultiGetRequest mget = new MultiGetRequest(executor, connectionManager); LOGGER.info("Reading segment sizes from servers for table: {}, timeoutMsec: {}", table, timeoutMsec); CompletionService<GetMethod> completionService = mget.execute(serverUrls, timeoutMsec); Map<String, List<SegmentSizeInfo>> serverSegmentSizes = new HashMap<>(serverEndPoints.size()); for (int i = 0; i < serverUrls.size(); i++) { GetMethod getMethod = null; try { getMethod = completionService.take().get(); URI uri = getMethod.getURI(); String instance = endpointsToServers.get(uri.getHost() + ":" + uri.getPort()); if (getMethod.getStatusCode() >= 300) { LOGGER.error("Server: {} returned error: {}", instance, getMethod.getStatusCode()); continue; } TableSizeInfo tableSizeInfo = new ObjectMapper().readValue(getMethod.getResponseBodyAsString(), TableSizeInfo.class); serverSegmentSizes.put(instance, tableSizeInfo.segments); } catch (InterruptedException e) { LOGGER.warn("Interrupted exception while reading segment size for table: {}", table, e); } catch (ExecutionException e) { if (Throwables.getRootCause(e) instanceof SocketTimeoutException) { LOGGER.warn("Server request to read table size was timed out for table: {}", table, e); } else if (Throwables.getRootCause(e) instanceof ConnectTimeoutException) { LOGGER.warn("Server request to read table size timed out waiting for connection. table: {}", table, e); } else if (Throwables.getRootCause(e) instanceof ConnectionPoolTimeoutException) { LOGGER.warn( "Server request to read table size timed out on getting a connection from pool, table: {}", table, e); } else { LOGGER.warn("Execution exception while reading segment sizes for table: {}", table, e); } } catch (Exception e) { LOGGER.warn("Error while reading segment sizes for table: {}", table); } finally { if (getMethod != null) { getMethod.releaseConnection(); } } } LOGGER.info("Finished reading segment sizes for table: {}", table); return serverSegmentSizes; } }