Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.aliyun.odps.mapred.bridge; import java.net.URL; import java.net.URLClassLoader; import org.apache.commons.lang.StringUtils; import com.aliyun.odps.Column; import com.aliyun.odps.io.Writable; import com.aliyun.odps.io.WritableUtils; import com.aliyun.odps.mapred.conf.BridgeJobConf; import com.aliyun.odps.udf.StandaloneUDTF; import com.aliyun.odps.udf.UDFException; public abstract class LotTaskUDTF extends StandaloneUDTF { protected BridgeJobConf conf; protected Column[] inputSchema; public LotTaskUDTF() { URL url = this.getClass().getClassLoader().getResource("jobconf.xml"); if (url == null) { URL[] urls = ((URLClassLoader) this.getClass().getClassLoader()).getURLs(); throw new RuntimeException( "Job configure file jobconf.xml not found. Classpath:" + StringUtils.join(urls, ":")); } conf = new BridgeJobConf(false); conf.addResource("jobconf.xml"); } /** * A hack to work around with protected method forward(...) * * @param objs */ public void collect(Object[] objs) { try { forward(objs); } catch (UDFException e) { throw new RuntimeException(e); } } /** * Deep copy of writable objects. Not that different from primative types, the * references within the writable array are also reused. * * @param objs * @return object array */ protected Object[] writableDeepCopy(Object[] objs) { Writable[] rt = new Writable[objs.length]; for (int i = 0; i < objs.length; i++) { if (objs[i] != null) { rt[i] = (Writable) WritableUtils.clone((Writable) objs[i], conf); } } return rt; } @Override public void process(Object[] unused) throws UDFException { } }