Java tutorial
/* * #%L * ACS AEM Tools Bundle * %% * Copyright (C) 2015 Adobe * %% * 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. * #L% */ package com.adobe.acs.tools.csv.impl; import com.day.text.csv.Csv; import org.apache.commons.io.IOUtils; import org.apache.commons.io.LineIterator; import org.apache.commons.lang.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintStream; import java.util.Iterator; public class CsvUtil { private static final Logger log = LoggerFactory.getLogger(CsvUtil.class); public static final String TERMINATED = "_LINE_TERMINATED"; /** * Interrogates the Request parameters and returns a prepared and parsed set of rows from the CSV file. * * @param params the Request parameters * @return The rows from the uploaded CSV file * @throws IOException */ public static Iterator<String[]> getRowsFromCsv(final Parameters params) throws IOException { final Csv csv = new Csv(); InputStream is = params.getFile(); if (params.getDelimiter() != null) { log.debug("Setting Field Delimiter to [ {} ]", params.getDelimiter()); csv.setFieldDelimiter(params.getDelimiter()); } if (params.getSeparator() != null) { log.debug("Setting Field Separator to [ {} ]", params.getSeparator()); csv.setFieldSeparatorRead(params.getSeparator()); } // Hack to prevent empty-value ending lines from breaking is = terminateLines(is, params.getSeparator() != null ? params.getSeparator() : csv.getFieldSeparatorRead(), params.getCharset()); return csv.read(is, params.getCharset()); } /** * Adds a populated terminating field to the ends of CSV entries. * If the last entry in a CSV row is empty, the CSV library has difficulty understanding that is the end of the row. * * @param is the CSV file as an inputstream * @param separator The field separator * @param charset The charset * @return An inputstream that is the same as is, but each line has a populated line termination entry * @throws IOException */ public static InputStream terminateLines(final InputStream is, final char separator, final String charset) throws IOException { final ByteArrayOutputStream baos = new ByteArrayOutputStream(); final PrintStream printStream = new PrintStream(baos); final LineIterator lineIterator = IOUtils.lineIterator(is, charset); while (lineIterator.hasNext()) { String line = StringUtils.stripToNull(lineIterator.next()); if (line != null) { line += separator + TERMINATED; printStream.println(line); } } return new ByteArrayInputStream(baos.toByteArray()); } }