1 /* 2 * Copyright (c) 1999, 2018, 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 java.util.regex; 27 28 /** 29 * Unchecked exception thrown to indicate a syntax error in a 30 * regular-expression pattern. 31 * 32 * @author unascribed 33 * @since 1.4 34 * @spec JSR-51 35 */ 36 37 public class PatternSyntaxException 38 extends IllegalArgumentException 39 { 40 @java.io.Serial 41 private static final long serialVersionUID = -3864639126226059218L; 42 43 private final String desc; 44 private final String pattern; 45 private final int index; 46 47 /** 48 * Constructs a new instance of this class. 49 * 50 * @param desc 51 * A description of the error 52 * 53 * @param regex 54 * The erroneous pattern 55 * 56 * @param index 57 * The approximate index in the pattern of the error, 58 * or {@code -1} if the index is not known 59 */ 60 public PatternSyntaxException(String desc, String regex, int index) { 61 this.desc = desc; 62 this.pattern = regex; 63 this.index = index; 64 } 65 66 /** 67 * Retrieves the error index. 68 * 69 * @return The approximate index in the pattern of the error, 70 * or {@code -1} if the index is not known 71 */ 72 public int getIndex() { 73 return index; 74 } 75 76 /** 77 * Retrieves the description of the error. 78 * 79 * @return The description of the error 80 */ 81 public String getDescription() { 82 return desc; 83 } 84 85 /** 86 * Retrieves the erroneous regular-expression pattern. 87 * 88 * @return The erroneous pattern 89 */ 90 public String getPattern() { 91 return pattern; 92 } 93 94 /** 95 * Returns a multi-line string containing the description of the syntax 96 * error and its index, the erroneous regular-expression pattern, and a 97 * visual indication of the error index within the pattern. 98 * 99 * @return The full detail message 100 */ 101 public String getMessage() { 102 StringBuilder sb = new StringBuilder(); 103 sb.append(desc); 104 if (index >= 0) { 105 sb.append(" near index "); 106 sb.append(index); 107 } 108 sb.append(System.lineSeparator()); 109 sb.append(pattern); 110 if (index >= 0 && pattern != null && index < pattern.length()) { 111 sb.append(System.lineSeparator()); 112 for (int i = 0; i < index; i++) sb.append(' '); 113 sb.append('^'); 114 } 115 return sb.toString(); 116 } 117 118 }