Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
StringUtils |
|
| 4.0;4 |
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 | ||
18 | package org.apache.any23.util; | |
19 | ||
20 | /** | |
21 | * This class provides a set of string utility methods. | |
22 | * | |
23 | * @author Michele Mostarda (mostarda@fbk.eu) | |
24 | */ | |
25 | public class StringUtils { | |
26 | ||
27 | /** | |
28 | * Joins the given input sting <code>data</code> list | |
29 | * using the specified <code>delimiter</code>. | |
30 | * | |
31 | * @param delimiter string delimiter. | |
32 | * @param data list of data to be joined. | |
33 | * @return the joined string. | |
34 | */ | |
35 | public static String join(String delimiter, String... data) { | |
36 | 0 | final StringBuilder sb = new StringBuilder(); |
37 | 0 | for (int i = 0; i < data.length; i++) { |
38 | 0 | sb.append(data[i]); |
39 | 0 | if (i >= data.length - 1) { |
40 | 0 | break; |
41 | } | |
42 | 0 | sb.append(delimiter); |
43 | } | |
44 | 0 | return sb.toString(); |
45 | } | |
46 | ||
47 | /** | |
48 | * Counts how many times <code>content</code> appears within <code>container</code> | |
49 | * without string overlapping. | |
50 | * | |
51 | * @param container container string. | |
52 | * @param content content string. | |
53 | * @return occurrences count. | |
54 | */ | |
55 | public static int countOccurrences(String container, String content) { | |
56 | 0 | int lastIndex, currIndex = 0, occurrences = 0; |
57 | while(true) { | |
58 | 0 | lastIndex = container.indexOf(content, currIndex); |
59 | 0 | if(lastIndex == -1) { |
60 | 0 | break; |
61 | } | |
62 | 0 | currIndex = lastIndex + content.length(); |
63 | 0 | occurrences++; |
64 | } | |
65 | 0 | return occurrences; |
66 | } | |
67 | ||
68 | /** | |
69 | * Counts the number of <code>NL</code> in the given <i>in</i> string. | |
70 | * | |
71 | * @param in input string. | |
72 | * @return the number of new line chars. | |
73 | */ | |
74 | public static int countNL(String in) { | |
75 | 0 | return countOccurrences(in, "\n"); |
76 | } | |
77 | ||
78 | ||
79 | /** | |
80 | * Check whether string <code>candidatePrefix</code> is prefix of string <code>container</code>. | |
81 | * | |
82 | * @param candidatePrefix | |
83 | * @param container | |
84 | * @return | |
85 | */ | |
86 | public static boolean isPrefix(String candidatePrefix, String container) { | |
87 | 0 | if(candidatePrefix == null || container == null) { |
88 | 0 | throw new NullPointerException("Arguments must be not null."); |
89 | } | |
90 | 0 | if(candidatePrefix.length() > container.length()) { |
91 | 0 | return false; |
92 | } | |
93 | 0 | for(int i = 0; i < candidatePrefix.length(); i++) { |
94 | 0 | if(candidatePrefix.charAt(i) != container.charAt(i)) { |
95 | 0 | return false; |
96 | } | |
97 | } | |
98 | 0 | return true; |
99 | } | |
100 | ||
101 | /** | |
102 | * Check whether string <code>candidateSuffix</code> is suffix of string <code>container</code>. | |
103 | * | |
104 | * @param candidateSuffix | |
105 | * @param container | |
106 | * @return | |
107 | */ | |
108 | public static boolean isSuffix(String candidateSuffix, String container) { | |
109 | 0 | if(candidateSuffix == null || container == null) { |
110 | 0 | throw new NullPointerException("Arguments must be not null."); |
111 | } | |
112 | 0 | if(candidateSuffix.length() > container.length()) { |
113 | 0 | return false; |
114 | } | |
115 | 0 | final int lenDiff = container.length() - candidateSuffix.length(); |
116 | 0 | for(int i = candidateSuffix.length() - 1; i >= 0; i--) { |
117 | 0 | if(candidateSuffix.charAt(i) != container.charAt(i + lenDiff)) { |
118 | 0 | return false; |
119 | } | |
120 | } | |
121 | 0 | return true; |
122 | } | |
123 | ||
124 | /** | |
125 | * Escapes all the unescaped double quotes when needed. | |
126 | * | |
127 | * @param in input string. | |
128 | * @return unescaped output. | |
129 | */ | |
130 | public static String escapeDoubleQuotes(String in) { | |
131 | 0 | final StringBuilder out = new StringBuilder(); |
132 | 0 | boolean escaped = false; |
133 | char current; | |
134 | 0 | for(int i = 0; i < in.length(); i++) { |
135 | 0 | current = in.charAt(i); |
136 | 0 | if(current == '\\') { |
137 | 0 | escaped = !escaped; |
138 | 0 | } else if(current == '"' && !escaped) { |
139 | 0 | out.append('\\'); |
140 | } | |
141 | 0 | out.append(current); |
142 | } | |
143 | 0 | return out.toString(); |
144 | } | |
145 | ||
146 | /** | |
147 | * Escapes the <code>in</code> string as <b>JSON</b> string | |
148 | * to let it being embeddable within a string field. | |
149 | * | |
150 | * @param in string to be escaped. | |
151 | * @return escaped string. | |
152 | */ | |
153 | public static String escapeAsJSONString(String in) { | |
154 | 0 | return escapeDoubleQuotes( in.replaceAll("\n", "\\\\n") ); |
155 | } | |
156 | ||
157 | /** | |
158 | * Builds a string composed of the given char <code>c<code/> <code>n</code> times. | |
159 | * | |
160 | * @param c char to be multiplied. | |
161 | * @param times number of times. | |
162 | * @return the string containing the multiplied char. | |
163 | */ | |
164 | public static String multiply(char c, int times) { | |
165 | 0 | if(times <= 0) throw new IllegalArgumentException("Invalid number of times, must be > 0 ."); |
166 | 0 | final char[] buffer = new char[times]; |
167 | 0 | for(int i = 0; i < times; i++) { |
168 | 0 | buffer[i] = c; |
169 | } | |
170 | 0 | return new String(buffer); |
171 | } | |
172 | ||
173 | 0 | private StringUtils() {} |
174 | } |