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 org.apache.marmotta.kiwi.loader.pgsql; import org.apache.commons.lang3.math.NumberUtils; import org.apache.marmotta.kiwi.loader.csv.*; import org.apache.marmotta.kiwi.model.rdf.*; import org.joda.time.DateTime; import org.openrdf.model.URI; import org.postgresql.PGConnection; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.supercsv.cellprocessor.Optional; import org.supercsv.cellprocessor.constraint.NotNull; import org.supercsv.cellprocessor.ift.CellProcessor; import org.supercsv.encoder.DefaultCsvEncoder; import org.supercsv.io.CsvListWriter; import org.supercsv.prefs.CsvPreference; import org.supercsv.util.CsvContext; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.sql.Connection; import java.sql.SQLException; import java.util.Arrays; import java.util.Date; import java.util.List; import java.util.Locale; /** * Add file description here! * * @author Sebastian Schaffert (sschaffert@apache.org) */ public class PGCopyUtil { private static Logger log = LoggerFactory.getLogger(PGCopyUtil.class); final static CellProcessor[] nodeProcessors = new CellProcessor[] { new NotNull(), // node ID new NodeTypeProcessor(), // ntype new NotNull(), // svalue new Optional(), // dvalue new Optional(), // ivalue new SQLDateTimeProcessor(), // tvalue new Optional(), // tzoffset new Optional(new SQLBooleanProcessor()), // bvalue new Optional(new NodeIDProcessor()), // ltype new Optional(new LanguageProcessor()), // lang new SQLTimestampProcessor(), // createdAt }; final static CellProcessor[] tripleProcessors = new CellProcessor[] { new NotNull(), // triple ID new NodeIDProcessor(), // subject new NodeIDProcessor(), // predicate new NodeIDProcessor(), // object new Optional(new NodeIDProcessor()), // context new Optional(new NodeIDProcessor()), // creator new SQLBooleanProcessor(), // inferred new SQLBooleanProcessor(), // deleted new SQLTimestampProcessor(), // createdAt new SQLTimestampProcessor(), // deletedAt }; // PostgreSQL expects the empty string to be quoted to distinguish between null and empty final static CsvPreference nodesPreference = new CsvPreference.Builder('"', ',', "\r\n") .useEncoder(new DefaultCsvEncoder() { /** * {@inheritDoc} */ @Override public String encode(String input, CsvContext context, CsvPreference preference) { if ("".equals(input)) { return "\"\""; } else { return super.encode(input, context, preference); } } }).build(); /** * Return a PGConnection wrapped by the tomcat connection pool so we are able to access PostgreSQL specific functionality. * @param con * @return */ public static PGConnection getWrappedConnection(Connection con) throws SQLException { if (con instanceof PGConnection) { return (PGConnection) con; } else { return (PGConnection) ((javax.sql.PooledConnection) con).getConnection(); } } public static void flushTriples(Iterable<KiWiTriple> tripleBacklog, OutputStream out) throws IOException { CsvListWriter writer = new CsvListWriter(new OutputStreamWriter(out), CsvPreference.STANDARD_PREFERENCE); // reuse the same array to avoid unnecessary object allocation Object[] rowArray = new Object[10]; List<Object> row = Arrays.asList(rowArray); for (KiWiTriple t : tripleBacklog) { rowArray[0] = t.getId(); rowArray[1] = t.getSubject(); rowArray[2] = t.getPredicate(); rowArray[3] = t.getObject(); rowArray[4] = t.getContext(); rowArray[5] = t.getCreator(); rowArray[6] = t.isInferred(); rowArray[7] = t.isDeleted(); rowArray[8] = t.getCreated(); rowArray[9] = t.getDeletedAt(); writer.write(row, tripleProcessors); } writer.close(); } public static void flushNodes(Iterable<KiWiNode> nodeBacklog, OutputStream out) throws IOException { CsvListWriter writer = new CsvListWriter(new OutputStreamWriter(out), nodesPreference); // reuse the same array to avoid unnecessary object allocation Object[] rowArray = new Object[11]; List<Object> row = Arrays.asList(rowArray); for (KiWiNode n : nodeBacklog) { if (n instanceof KiWiUriResource) { KiWiUriResource u = (KiWiUriResource) n; createNodeList(rowArray, u.getId(), u.getClass(), u.stringValue(), null, null, null, null, null, null, null, u.getCreated()); } else if (n instanceof KiWiAnonResource) { KiWiAnonResource a = (KiWiAnonResource) n; createNodeList(rowArray, a.getId(), a.getClass(), a.stringValue(), null, null, null, null, null, null, null, a.getCreated()); } else if (n instanceof KiWiIntLiteral) { KiWiIntLiteral l = (KiWiIntLiteral) n; createNodeList(rowArray, l.getId(), l.getClass(), l.getContent(), l.getDoubleContent(), l.getIntContent(), null, null, null, l.getDatatype(), l.getLocale(), l.getCreated()); } else if (n instanceof KiWiDoubleLiteral) { KiWiDoubleLiteral l = (KiWiDoubleLiteral) n; createNodeList(rowArray, l.getId(), l.getClass(), l.getContent(), l.getDoubleContent(), null, null, null, null, l.getDatatype(), l.getLocale(), l.getCreated()); } else if (n instanceof KiWiBooleanLiteral) { KiWiBooleanLiteral l = (KiWiBooleanLiteral) n; createNodeList(rowArray, l.getId(), l.getClass(), l.getContent(), null, null, null, null, l.booleanValue(), l.getDatatype(), l.getLocale(), l.getCreated()); } else if (n instanceof KiWiDateLiteral) { KiWiDateLiteral l = (KiWiDateLiteral) n; createNodeList(rowArray, l.getId(), l.getClass(), l.getContent(), null, null, l.getDateContent(), l.getDateContent().getZone().getOffset(l.getDateContent()) / 1000, null, l.getDatatype(), l.getLocale(), l.getCreated()); } else if (n instanceof KiWiStringLiteral) { KiWiStringLiteral l = (KiWiStringLiteral) n; Double dbl_value = null; Long lng_value = null; if (l.getContent().length() < 64 && NumberUtils.isNumber(l.getContent())) { try { dbl_value = Double.parseDouble(l.getContent()); lng_value = Long.parseLong(l.getContent()); } catch (NumberFormatException ex) { // ignore, keep NaN } } createNodeList(rowArray, l.getId(), l.getClass(), l.getContent(), dbl_value, lng_value, null, null, null, l.getDatatype(), l.getLocale(), l.getCreated()); } else { log.warn("unknown node type, cannot flush to import stream: {}", n.getClass()); } writer.write(row, nodeProcessors); } writer.close(); } private static void createNodeList(Object[] a, Long id, Class type, String content, Double dbl, Long lng, DateTime date, Integer tzoffset, Boolean bool, URI dtype, Locale lang, Date created) { a[0] = id; a[1] = type; a[2] = content; a[3] = dbl; a[4] = lng; a[5] = date; a[6] = tzoffset; a[7] = bool; a[8] = dtype; a[9] = lang != null ? lang.getLanguage() : ""; a[10] = created; } }