Java tutorial
/************************************************************************* * * * This file is part of the 20n/act project. * * 20n/act enables DNA prediction for synthetic biology/bioengineering. * * Copyright (C) 2017 20n Labs, Inc. * * * * Please direct all queries to act@20n.com. * * * * This program is free software: you can redistribute it and/or modify * * it under the terms of the GNU General Public License as published by * * the Free Software Foundation, either version 3 of the License, or * * (at your option) any later version. * * * * This program 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 General Public License for more details. * * * * You should have received a copy of the GNU General Public License * * along with this program. If not, see <http://www.gnu.org/licenses/>. * * * *************************************************************************/ package com.act.utils; import org.apache.commons.csv.CSVFormat; import org.apache.commons.csv.CSVPrinter; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.util.ArrayList; import java.util.List; import java.util.Map; // TODO: move this and TSVParser to an analysis utility class. No reason for them to live deep in package hierarchies. public class TSVWriter<K, V> implements AutoCloseable { public static final CSVFormat TSV_FORMAT = CSVFormat.newFormat('\t').withRecordSeparator('\n').withQuote('"') .withIgnoreEmptyLines(true); private List<K> header; private CSVPrinter printer; public TSVWriter(List<K> header) { this.header = header; } public void open(File f) throws IOException { String[] headerStrings = new String[header.size()]; for (int i = 0; i < header.size(); i++) { headerStrings[i] = header.get(i).toString(); } printer = new CSVPrinter(new FileWriter(f), TSV_FORMAT.withHeader(headerStrings)); } public void open(File f, Boolean append) throws IOException { if (!append) { open(f); } else { printer = new CSVPrinter(new FileWriter(f, true), TSV_FORMAT); } } @Override public void close() throws IOException { if (printer != null) { printer.close(); printer = null; } } public void append(Map<K, V> row) throws IOException { List<V> vals = new ArrayList<>(header.size()); for (K field : header) { vals.add(row.get(field)); } printer.printRecord(vals); } public void append(List<Map<K, V>> rows) throws IOException { for (Map<K, V> row : rows) { append(row); } printer.flush(); } public void flush() throws IOException { printer.flush(); } }