001/////////////////////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code and other text files for adherence to a set of rules. 003// Copyright (C) 2001-2024 the original author or authors. 004// 005// This library is free software; you can redistribute it and/or 006// modify it under the terms of the GNU Lesser General Public 007// License as published by the Free Software Foundation; either 008// version 2.1 of the License, or (at your option) any later version. 009// 010// This library is distributed in the hope that it will be useful, 011// but WITHOUT ANY WARRANTY; without even the implied warranty of 012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 013// Lesser General Public License for more details. 014// 015// You should have received a copy of the GNU Lesser General Public 016// License along with this library; if not, write to the Free Software 017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 018/////////////////////////////////////////////////////////////////////////////////////////////// 019 020package com.puppycrawl.tools.checkstyle.checks; 021 022import java.nio.charset.StandardCharsets; 023import java.util.Arrays; 024 025/** 026 * Represents the options for line separator settings. 027 * 028 * @see NewlineAtEndOfFileCheck 029 */ 030public enum LineSeparatorOption { 031 032 /** Windows-style line separators. **/ 033 CRLF("\r\n"), 034 035 /** Mac-style line separators. **/ 036 CR("\r"), 037 038 /** Unix-style line separators. **/ 039 LF("\n"), 040 041 /** 042 * Matches CR, LF and CRLF line separators. 043 * Only the length is used - the actual value is ignored. 044 */ 045 LF_CR_CRLF("#"), 046 047 /** System default line separators. **/ 048 SYSTEM(System.getProperty("line.separator")); 049 050 /** The line separator representation. */ 051 private final byte[] lineSeparator; 052 053 /** 054 * Creates a new {@code LineSeparatorOption} instance. 055 * 056 * @param sep the line separator, e.g. "\r\n" 057 */ 058 LineSeparatorOption(String sep) { 059 lineSeparator = sep.getBytes(StandardCharsets.US_ASCII); 060 } 061 062 /** 063 * Checks that bytes is equal to the byte representation of this line separator. 064 * 065 * @param bytes a bytes array to check 066 * @return if bytes is equal to the byte representation 067 * of this line separator 068 */ 069 public boolean matches(byte... bytes) { 070 final boolean result; 071 if (this == LF_CR_CRLF) { 072 // this silently assumes LF and CR are of length 1 073 // CRLF always matches LF, so CRLF isn't tested 074 result = LF.matches(bytes) || CR.matches(bytes); 075 } 076 else { 077 result = Arrays.equals(bytes, lineSeparator); 078 } 079 return result; 080 } 081 082 /** 083 * Returns length of file separator in bytes. 084 * 085 * @return the length of the file separator in bytes, 086 * e.g. 1 for CR, 2 for CRLF, ... 087 */ 088 public int length() { 089 return lineSeparator.length; 090 } 091 092}