1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.jexl3.parser;
18
19 /**
20 * Identifiers, variables and registers.
21 */
22 public class ASTIdentifierAccess extends JexlNode {
23 /**
24 */
25 private static final long serialVersionUID = 1L;
26 /**
27 * Parse an identifier which must be of the form:
28 * 0|([1-9][0-9]*)
29 * @param id the identifier
30 * @return an integer or null
31 */
32 public static Integer parseIdentifier(final String id) {
33 // hand coded because the was no way to fail on leading '0's using NumberFormat
34 if (id != null) {
35 final int length = id.length();
36 int val = 0;
37 for (int i = 0; i < length; ++i) {
38 final char c = id.charAt(i);
39 // leading 0s but no just 0, NaN
40 if (c == '0') {
41 if (length == 1) {
42 return 0;
43 }
44 if (val == 0) {
45 return null;
46 }
47 } // any non numeric, NaN
48 else if (c < '0' || c > '9') {
49 return null;
50 }
51 val *= 10;
52 val += c - '0';
53 }
54 return val;
55 }
56 return null;
57 }
58 private String name;
59
60 private Integer identifier;
61
62 ASTIdentifierAccess(final int id) {
63 super(id);
64 }
65
66 public Object getIdentifier() {
67 return identifier != null ? identifier : name;
68 }
69
70 public String getName() {
71 return name;
72 }
73
74 /**
75 * Whether this is a Jxlt based identifier.
76 * @return true if `..${...}...`, false otherwise
77 */
78 public boolean isExpression() {
79 return false;
80 }
81
82 @Override
83 public boolean isGlobalVar() {
84 return !isSafe() && !isExpression();
85 }
86
87 /**
88 * Whether this is a dot or a question-mark-dot aka safe-navigation access.
89 * @return true is ?., false if .
90 */
91 public boolean isSafe() {
92 return false;
93 }
94
95 @Override
96 public Object jjtAccept(final ParserVisitor visitor, final Object data) {
97 return visitor.visit(this, data);
98 }
99
100 void setIdentifier(final String id) {
101 name = id;
102 identifier = parseIdentifier(id);
103 }
104
105 @Override
106 public String toString() {
107 return name;
108 }
109 }