001//////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code for adherence to a set of rules. 003// Copyright (C) 2001-2016 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.naming; 021 022import java.util.regex.Pattern; 023 024import com.puppycrawl.tools.checkstyle.api.AbstractCheck; 025import com.puppycrawl.tools.checkstyle.api.DetailAST; 026import com.puppycrawl.tools.checkstyle.api.FullIdent; 027import com.puppycrawl.tools.checkstyle.api.TokenTypes; 028import com.puppycrawl.tools.checkstyle.utils.CommonUtils; 029 030/** 031 * <p> 032 * Checks that package names conform to a format specified 033 * by the format property. The format is a 034 * {@link Pattern regular expression} 035 * and defaults to 036 * <strong>^[a-z]+(\.[a-zA-Z_][a-zA-Z_0-9_]*)*$</strong>. 037 * </p> 038 * <p> 039 * The default format has been chosen to match the requirements in the 040 * <a 041 * href="http://docs.oracle.com/javase/specs/jls/se8/html/jls-7.html"> 042 * Java Language specification</a> and the Sun coding conventions. 043 * However both underscores and uppercase letters are rather uncommon, 044 * so most projects should probably use 045 * <strong>^[a-z]+(\.[a-z][a-z0-9]*)*$</strong>. 046 * </p> 047 * <p> 048 * An example of how to configure the check is: 049 * </p> 050 * <pre> 051 * <module name="PackageName"/> 052 * </pre> 053 * <p> 054 * An example of how to configure the check for package names that begin with 055 * {@code com.puppycrawl.tools.checkstyle} is: 056 * </p> 057 * <pre> 058 * <module name="PackageName"> 059 * <property name="format" 060 * value="^com\.puppycrawl\.tools\.checkstyle(\.[a-zA-Z_][a-zA-Z_0-9]*)*$"/> 061 * </module> 062 * </pre> 063 * 064 * @author Oliver Burn 065 */ 066public class PackageNameCheck 067 extends AbstractCheck { 068 /** 069 * A key is pointing to the warning message text in "messages.properties" 070 * file. 071 */ 072 public static final String MSG_KEY = "name.invalidPattern"; 073 074 /** The format string of the regexp. */ 075 // Uppercase letters seem rather uncommon, but they're allowed in 076 // http://docs.oracle.com/javase/specs/ 077 // second_edition/html/packages.doc.html#40169 078 private String format = "^[a-z]+(\\.[a-zA-Z_][a-zA-Z0-9_]*)*$"; 079 /** The regexp to match against. */ 080 private Pattern regexp = Pattern.compile(format); 081 082 /** 083 * Set the format to the specified regular expression. 084 * @param format a {@code String} value 085 * @throws org.apache.commons.beanutils.ConversionException unable to parse format 086 */ 087 public final void setFormat(String format) { 088 this.format = format; 089 regexp = CommonUtils.createPattern(format); 090 } 091 092 @Override 093 public int[] getDefaultTokens() { 094 return getAcceptableTokens(); 095 } 096 097 @Override 098 public int[] getAcceptableTokens() { 099 return new int[] {TokenTypes.PACKAGE_DEF}; 100 } 101 102 @Override 103 public int[] getRequiredTokens() { 104 return getAcceptableTokens(); 105 } 106 107 @Override 108 public void visitToken(DetailAST ast) { 109 final DetailAST nameAST = ast.getLastChild().getPreviousSibling(); 110 final FullIdent full = FullIdent.createFullIdent(nameAST); 111 if (!regexp.matcher(full.getText()).find()) { 112 log(full.getLineNo(), 113 full.getColumnNo(), 114 MSG_KEY, 115 full.getText(), 116 format); 117 } 118 } 119}