Java tutorial
/* Copyright 2008-2016 Gephi Authors : Eduardo Ramos <eduardo.ramos@gephi.org> Website : http://www.gephi.org This file is part of Gephi. DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. Copyright 2016 Gephi Consortium. All rights reserved. The contents of this file are subject to the terms of either the GNU General Public License Version 3 only ("GPL") or the Common Development and Distribution License("CDDL") (collectively, the "License"). You may not use this file except in compliance with the License. You can obtain a copy of the License at http://gephi.org/about/legal/license-notice/ or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the specific language governing permissions and limitations under the License. When distributing the software, include this License Header Notice in each file and include the License files at /cddl-1.0.txt and /gpl-3.0.txt. 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Contributor(s): Portions Copyrighted 2016 Gephi Consortium. */ package org.gephi.io.importer.plugin.file.spreadsheet; import java.io.FileInputStream; import java.io.IOException; import java.io.LineNumberReader; import java.nio.charset.Charset; import java.util.Arrays; import java.util.Collections; import org.apache.commons.csv.CSVParser; import org.gephi.io.importer.api.ImportUtils; import org.gephi.io.importer.plugin.file.spreadsheet.process.SpreadsheetGeneralConfiguration; import org.gephi.io.importer.plugin.file.spreadsheet.sheet.EmptySheet; import org.gephi.io.importer.plugin.file.spreadsheet.sheet.ErrorSheet; import org.gephi.io.importer.plugin.file.spreadsheet.sheet.SheetParser; import org.gephi.io.importer.plugin.file.spreadsheet.sheets.csv.CSVSheetParser; import org.gephi.utils.CharsetToolkit; import org.openide.filesystems.FileUtil; /** * * @author Eduardo Ramos */ public class ImporterSpreadsheetCSV extends AbstractImporterSpreadsheet { protected char fieldDelimiter = ','; protected Charset charset = Charset.forName("UTF-8"); @Override public SheetParser createParserWithoutHeaders() throws IOException { return createParser(false); } @Override public SheetParser createParser() throws IOException { boolean withFirstRecordAsHeader = generalConfig .getMode() == SpreadsheetGeneralConfiguration.Mode.NODES_TABLE || generalConfig.getMode() == SpreadsheetGeneralConfiguration.Mode.EDGES_TABLE; return createParser(withFirstRecordAsHeader); } private SheetParser createParser(boolean withFirstRecordAsHeader) throws IOException { try { CSVParser csvParser = SpreadsheetUtils.configureCSVParser(file, fieldDelimiter, charset, withFirstRecordAsHeader); return new CSVSheetParser(csvParser); } catch (Exception ex) { if (report != null) { SpreadsheetUtils.logError(report, ex.getMessage(), null); return EmptySheet.INSTANCE; } else { return new ErrorSheet(ex.getMessage()); } } } @Override public void refreshAutoDetections() { autoDetectCharset(); autoDetectFieldDelimiter(); super.refreshAutoDetections(); } private void autoDetectCharset() { //Try to auto-detect the charset: try { FileInputStream is = new FileInputStream(file); CharsetToolkit charsetToolkit = new CharsetToolkit(is); charsetToolkit.setDefaultCharset(Charset.forName("UTF-8")); charset = charsetToolkit.getCharset(); } catch (Exception ex) { } } private void autoDetectFieldDelimiter() { //Very simple naive detector but should work in most cases: try (LineNumberReader reader = ImportUtils.getTextReader(FileUtil.toFileObject(file))) { String line = reader.readLine(); //Check for typical delimiter chars in the header int commaCount = 0; int semicolonCount = 0; int tabCount = 0; int spaceCount = 0; boolean inQuote = false; for (char c : line.toCharArray()) { if (c == '"' || c == '\'') { inQuote = !inQuote; } if (!inQuote) { switch (c) { case ',': commaCount++; break; case ';': semicolonCount++; break; case '\t': tabCount++; break; case ' ': spaceCount++; break; } } } int max = Collections.max(Arrays.asList(commaCount, semicolonCount, tabCount, spaceCount)); if (commaCount == max) { fieldDelimiter = ','; } else if (semicolonCount == max) { fieldDelimiter = ';'; } else if (tabCount == max) { fieldDelimiter = '\t'; } else if (spaceCount == max) { fieldDelimiter = ' '; } } catch (IOException ex) { } } public char getFieldDelimiter() { return fieldDelimiter; } public void setFieldDelimiter(char fieldDelimiter) { this.fieldDelimiter = fieldDelimiter; } public Charset getCharset() { return charset; } public void setCharset(Charset charset) { this.charset = charset; } }