1 /* 2 * Copyright (c) 2010, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.nashorn.internal.runtime.regexp; 27 28 import static java.util.regex.Pattern.CASE_INSENSITIVE; 29 import static java.util.regex.Pattern.MULTILINE; 30 import static java.util.regex.Pattern.UNICODE_CASE; 31 32 import java.util.regex.Matcher; 33 import java.util.regex.Pattern; 34 import java.util.regex.PatternSyntaxException; 35 import jdk.nashorn.internal.runtime.ParserException; 36 37 /** 38 * Default regular expression implementation based on java.util.regex package. 39 * 40 * Note that this class is not thread-safe as it stores the current match result 41 * and the string being matched in instance fields. 42 */ 43 public class JdkRegExp extends RegExp { 44 45 /** Java regexp pattern to use for match. We compile to one of these */ 46 private Pattern pattern; 47 48 /** 49 * Construct a Regular expression from the given {@code source} and {@code flags} strings. 50 * 51 * @param source RegExp source string 52 * @param flags RegExp flag string 53 * @throws ParserException if flags is invalid or source string has syntax error. 54 */ 55 public JdkRegExp(final String source, final String flags) throws ParserException { 56 super(source, flags); 57 58 int intFlags = 0; 59 60 if (isIgnoreCase()) { 61 intFlags |= CASE_INSENSITIVE | UNICODE_CASE; 62 } 63 if (isMultiline()) { 64 intFlags |= MULTILINE; 65 } 66 67 try { 68 RegExpScanner parsed; 69 70 try { 71 parsed = RegExpScanner.scan(source); 72 } catch (final PatternSyntaxException e) { 73 // refine the exception with a better syntax error, if this 74 // passes, just rethrow what we have 75 Pattern.compile(source, intFlags); 76 throw e; 77 } 78 79 if (parsed != null) { 80 this.pattern = Pattern.compile(parsed.getJavaPattern(), intFlags); 81 this.groupsInNegativeLookahead = parsed.getGroupsInNegativeLookahead(); 82 } 83 } catch (final PatternSyntaxException e2) { 84 throwParserException("syntax", e2.getMessage()); 85 } catch (StackOverflowError e3) { 86 throw new RuntimeException(e3); 87 } 88 } 89 90 @Override 91 public RegExpMatcher match(final String str) { 92 if (pattern == null) { 93 return null; // never matches or similar, e.g. a[] 94 } 95 96 return new DefaultMatcher(str); 97 } 98 99 class DefaultMatcher implements RegExpMatcher { 100 final String input; 101 final Matcher defaultMatcher; 102 103 DefaultMatcher(final String input) { 104 this.input = input; 105 this.defaultMatcher = pattern.matcher(input); 106 } 107 108 @Override 109 public boolean search(final int start) { 110 return defaultMatcher.find(start); 111 } 112 113 @Override 114 public String getInput() { 115 return input; 116 } 117 118 @Override 119 public int start() { 120 return defaultMatcher.start(); 121 } 122 123 @Override 124 public int start(final int group) { 125 return defaultMatcher.start(group); 126 } 127 128 @Override 129 public int end() { 130 return defaultMatcher.end(); 131 } 132 133 @Override 134 public int end(final int group) { 135 return defaultMatcher.end(group); 136 } 137 138 @Override 139 public String group() { 140 return defaultMatcher.group(); 141 } 142 143 @Override 144 public String group(final int group) { 145 return defaultMatcher.group(group); 146 } 147 148 @Override 149 public int groupCount() { 150 return defaultMatcher.groupCount(); 151 } 152 } 153 154 }