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 * https://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.configuration2.interpol;
18
19 import static org.junit.jupiter.api.Assertions.assertEquals;
20 import static org.junit.jupiter.api.Assertions.assertNull;
21
22 import java.awt.event.KeyEvent;
23
24 import org.junit.jupiter.api.AfterEach;
25 import org.junit.jupiter.api.BeforeEach;
26 import org.junit.jupiter.api.Test;
27
28 /**
29 * Test class for ConstantLookup.
30 */
31 public class TestConstantLookup {
32 /** A public field that can be read by the lookup. */
33 public static final String FIELD = "Field that can be read";
34
35 /** A private field that cannot be read by the lookup. */
36 @SuppressWarnings("unused")
37 private static final String PRIVATE_FIELD = "PRIVATE";
38
39 /** The lookup object to be tested. */
40 private ConstantLookup lookup;
41
42 @BeforeEach
43 public void setUp() throws Exception {
44 lookup = new ConstantLookup();
45 }
46
47 /**
48 * Clears the test environment. Here the static cache of the constant lookup class is wiped out.
49 */
50 @AfterEach
51 public void tearDown() {
52 ConstantLookup.clear();
53 }
54
55 /**
56 * Tests accessing the cache by querying a variable twice.
57 */
58 @Test
59 void testLookupCache() {
60 testLookupConstant();
61 testLookupConstant();
62 }
63
64 /**
65 * Tests resolving a valid constant.
66 */
67 @Test
68 void testLookupConstant() {
69 assertEquals(FIELD, lookup.lookup(variable("FIELD")));
70 }
71
72 /**
73 * Tries to resolve a variable with an invalid syntax: The name does not contain a dot as a field separator.
74 */
75 @Test
76 void testLookupInvalidSyntax() {
77 assertNull(lookup.lookup("InvalidVariableName"));
78 }
79
80 /**
81 * Tests resolving a non existing constant. Result should be null.
82 */
83 @Test
84 void testLookupNonExisting() {
85 assertNull(lookup.lookup(variable("NO_FIELD")));
86 }
87
88 /**
89 * Tests resolving a non string constant. Then looks the same variable up from the cache.
90 */
91 @Test
92 void testLookupNonStringFromCache() {
93 final String var = KeyEvent.class.getName() + ".VK_ESCAPE";
94 final Object expected = KeyEvent.VK_ESCAPE;
95 assertEquals(expected, lookup.lookup(var));
96 assertEquals(expected, lookup.lookup(var));
97 }
98
99 /**
100 * Tests looking up a null variable.
101 */
102 @Test
103 void testLookupNull() {
104 assertNull(lookup.lookup(null));
105 }
106
107 /**
108 * Tests resolving a private constant. Because a private field cannot be accessed this should again yield null.
109 */
110 @Test
111 void testLookupPrivate() {
112 assertNull(lookup.lookup(variable("PRIVATE_FIELD")));
113 }
114
115 /**
116 * Tests resolving a field from an unknown class.
117 */
118 @Test
119 void testLookupUnknownClass() {
120 assertNull(lookup.lookup("org.apache.commons.configuration.NonExistingConfig." + FIELD));
121 }
122
123 /**
124 * Generates the name of a variable for a lookup operation based on the given field name of this class.
125 *
126 * @param field the field name
127 * @return the variable for looking up this field
128 */
129 private String variable(final String field) {
130 return getClass().getName() + '.' + field;
131 }
132 }