1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.tradefed.util;
18 
19 import java.util.Map;
20 import java.util.regex.Matcher;
21 import java.util.regex.Pattern;
22 
23 /** Utility class for escaping strings for common string manipulation. */
24 public class StringUtil {
25 
26     /**
27      * Expand all variables in a given string with their values in the map.
28      *
29      * <pre>{@code
30      * Map<String, String> valueMap = new HashMap<>() {
31      *   put("FOO", "trade");
32      *   put("BAR", "federation");
33      * };
34      * String str = StringUtil.expand("${FOO}.${BAR}", valueMap);
35      * assert str.equals("trade.federation");
36      * }</pre>
37      *
38      * @param str the source {@link String} to expand
39      * @return the map with the variable names and values
40      */
expand(String str, Map<String, String> valueMap)41     public static String expand(String str, Map<String, String> valueMap) {
42         final StringBuffer sb = new StringBuffer();
43         final Pattern p = Pattern.compile("\\$\\{([^\\{\\}]+)\\}");
44         final Matcher m = p.matcher(str);
45         while (m.find()) {
46             final String key = m.group(1);
47             final String value = valueMap.getOrDefault(key, "");
48             m.appendReplacement(sb, Matcher.quoteReplacement(value));
49         }
50         m.appendTail(sb);
51         return sb.toString();
52     }
53 }
54