Java tutorial
/** * This work was created by the National Center for Ecological Analysis and Synthesis * at the University of California Santa Barbara (UCSB). * * Copyright 2011 Regents of the University of California * * 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 ezid; import java.util.HashMap; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * A simple client application for the EZID Service that allows calling applications * to set up a connection to EZID and maintain that connection across a series of * service invocations. Service call requests are maintained in a queue and submitted * to EZID asynchronously, allowing the rate of requests to the EZID service to be * controlled by the calling application. Callback methods are provided to allow * the calling application to be notified of the error status of service invocations. * This client should be mainly useful to calling applications that need to issue many * requests to the EZID service. * * @author Matthew Jones, NCEAS, UC Santa Barbara */ public class EZIDClient { private String USERNAME = "apitest"; private String PASSWORD = "apitest"; private EZIDService ezid = null; private ExecutorService executor = null; protected static Log log = LogFactory.getLog(EZIDClient.class); public EZIDClient() { ezid = new EZIDService(); startExecutorLoop(); } public boolean login(String username, String password) { boolean loginSuccess = false; USERNAME = username; PASSWORD = password; try { ezid.login(USERNAME, PASSWORD); loginSuccess = true; } catch (EZIDException e) { loginSuccess = false; } return loginSuccess; } public void create(String identifier, HashMap<String, String> metadata) throws InterruptedException { EZIDServiceRequest request = new EZIDServiceRequest(ezid, EZIDServiceRequest.CREATE, identifier, metadata); executor.execute(request); } public void delete(String identifier) throws InterruptedException { EZIDServiceRequest request = new EZIDServiceRequest(ezid, EZIDServiceRequest.DELETE, identifier); executor.execute(request); } public void setMetadata(String identifier, HashMap<String, String> metadata) throws InterruptedException { EZIDServiceRequest request = new EZIDServiceRequest(ezid, EZIDServiceRequest.SETMETADATA, identifier, metadata); executor.execute(request); } private void startExecutorLoop() { // Query the runtime to see how many CPUs are available, and configure that many threads Runtime runtime = Runtime.getRuntime(); int numCores = runtime.availableProcessors(); log.info("Number of cores available: " + numCores); executor = Executors.newFixedThreadPool(numCores); } public void shutdown() { log.info("Shutting down executor..."); // Stop the executor from accepting new requests and finishing existing Runnables executor.shutdown(); // Wait until all Runnables are finished while (!executor.isTerminated()) { // log.info("..."); } } }