Java tutorial
/** * Copyright (C) 2010-2016 Structr GmbH * * This file is part of Structr <http://structr.org>. * * Structr is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * Structr is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with Structr. If not, see <http://www.gnu.org/licenses/>. */ package org.structr.function; import java.io.StringReader; import java.util.LinkedList; import java.util.List; import java.util.Map; import org.apache.commons.csv.CSVFormat; import org.apache.commons.csv.CSVParser; import org.apache.commons.csv.CSVRecord; import org.apache.commons.csv.QuoteMode; import org.structr.core.GraphObject; import org.structr.schema.action.ActionContext; /** * */ public class FromCsvFunction extends UiFunction { public static final String ERROR_MESSAGE_FROM_CSV = "Usage: ${from_csv(source [, delimiter, quoteChar, recordSeparator])}. Example: ${from_csv('one;two;three')}"; public static final String ERROR_MESSAGE_FROM_CSV_JS = "Usage: ${{Structr.from_csv(src [, delimiter, quoteChar, recordSeparator])}}. Example: ${{Structr.from_csv('one;two;three')}}"; @Override public String getName() { return "from_csv()"; } @Override public Object apply(ActionContext ctx, final GraphObject entity, final Object[] sources) { if (sources != null && sources.length > 0) { if (sources[0] != null) { try { final List<Map<String, String>> objects = new LinkedList<>(); final String source = sources[0].toString(); String delimiter = ";"; String quoteChar = "\""; String recordSeparator = "\n"; switch (sources.length) { case 4: recordSeparator = (String) sources[3]; case 3: quoteChar = (String) sources[2]; case 2: delimiter = (String) sources[1]; break; } CSVFormat format = CSVFormat.newFormat(delimiter.charAt(0)).withHeader(); format = format.withQuote(quoteChar.charAt(0)); format = format.withRecordSeparator(recordSeparator); format = format.withIgnoreEmptyLines(true); format = format.withIgnoreSurroundingSpaces(true); format = format.withSkipHeaderRecord(true); format = format.withQuoteMode(QuoteMode.ALL); CSVParser parser = new CSVParser(new StringReader(source), format); for (final CSVRecord record : parser.getRecords()) { objects.add(record.toMap()); } return objects; } catch (Throwable t) { t.printStackTrace(); } } return ""; } return usage(ctx.isJavaScriptContext()); } @Override public String usage(boolean inJavaScriptContext) { return (inJavaScriptContext ? ERROR_MESSAGE_FROM_CSV_JS : ERROR_MESSAGE_FROM_CSV); } @Override public String shortDescription() { return "Parses the given CSV string and returns a list objects"; } }