Java tutorial
/* * Copyright (c) 2011-2015 EPFL DATA Laboratory * Copyright (c) 2014-2015 The Squall Collaboration (see NOTICE) * * All rights reserved. * * 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 ch.epfl.data.squall.utilities; import backtype.storm.serialization.DefaultSerializationDelegate; import java.net.URLClassLoader; import java.net.MalformedURLException; import java.net.URL; import org.apache.commons.io.input.ClassLoaderObjectInputStream; import java.io.File; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.util.Map; import org.apache.log4j.Logger; /* * Used in local mode to deserialize for the REPL and DBToaster */ public class SquallSerializationDelegate extends DefaultSerializationDelegate { private static Logger LOG = Logger.getLogger(SquallSerializationDelegate.class); private URL classdir; @Override public void prepare(Map stormConf) { super.prepare(stormConf); LOG.info("Setting up SquallSerializationDelegate"); LOG.info(stormConf.toString()); try { String classdirPath = (String) stormConf.get("squall.classdir"); if (classdirPath != null) { classdir = new File(classdirPath).toURL(); LOG.info("Adding '" + classdir + "' as search path for deserializing"); } else { throw new RuntimeException( "Squall Serialization delegate was set, but option squall.classdir is empty"); } } catch (MalformedURLException e) { throw new RuntimeException(e); } } @Override public Object deserialize(byte[] bytes) { try { return super.deserialize(bytes); } catch (RuntimeException e) { try { if (classdir == null) throw e; URLClassLoader classloader = new URLClassLoader(new URL[] { classdir }, Thread.currentThread().getContextClassLoader()); // Read the object ByteArrayInputStream bis = new ByteArrayInputStream(bytes); ObjectInputStream ois = new ClassLoaderObjectInputStream(classloader, bis); Object ret = ois.readObject(); ois.close(); return ret; } catch (ClassNotFoundException error) { throw new RuntimeException(error); } catch (IOException error) { throw new RuntimeException(error); } } } }