Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
EnvironmentConfiguration |
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| 1.75;1,75 |
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.commons.configuration; | |
19 | ||
20 | import java.util.HashMap; | |
21 | ||
22 | /** | |
23 | * <p>A Configuration implementation that reads the platform specific | |
24 | * environment variables using the map returned by {@link System#getenv()}.</p> | |
25 | * | |
26 | * <p>This configuration implementation is read-only. It allows read access to the | |
27 | * defined OS environment variables, but their values cannot be changed. Any | |
28 | * attempts to add or remove a property will throw an | |
29 | * {@link UnsupportedOperationException}</p> | |
30 | * | |
31 | * <p>Usage of this class is easy: After an instance has been created the get | |
32 | * methods provided by the {@code Configuration} interface can be used | |
33 | * for querying environment variables, e.g.:</p> | |
34 | * | |
35 | * <pre> | |
36 | * Configuration envConfig = new EnvironmentConfiguration(); | |
37 | * System.out.println("JAVA_HOME=" + envConfig.getString("JAVA_HOME"); | |
38 | * </pre> | |
39 | * | |
40 | * @author <a href="mailto:nicolas.deloof@gmail.com">Nicolas De Loof</a> | |
41 | * @version $Id: EnvironmentConfiguration.java 1210171 2011-12-04 18:32:07Z oheger $ | |
42 | * @since 1.5 | |
43 | */ | |
44 | public class EnvironmentConfiguration extends MapConfiguration | |
45 | { | |
46 | /** | |
47 | * Create a Configuration based on the environment variables. | |
48 | * | |
49 | * @see System#getenv() | |
50 | */ | |
51 | public EnvironmentConfiguration() | |
52 | { | |
53 | 13 | super(new HashMap<String, Object>(System.getenv())); |
54 | 13 | } |
55 | ||
56 | /** | |
57 | * Adds a property to this configuration. Because this configuration is | |
58 | * read-only, this operation is not allowed and will cause an exception. | |
59 | * | |
60 | * @param key the key of the property to be added | |
61 | * @param value the property value | |
62 | */ | |
63 | @Override | |
64 | protected void addPropertyDirect(String key, Object value) | |
65 | { | |
66 | 1 | throw new UnsupportedOperationException("EnvironmentConfiguration is read-only!"); |
67 | } | |
68 | ||
69 | /** | |
70 | * Removes a property from this configuration. Because this configuration is | |
71 | * read-only, this operation is not allowed and will cause an exception. | |
72 | * | |
73 | * @param key the key of the property to be removed | |
74 | */ | |
75 | @Override | |
76 | public void clearProperty(String key) | |
77 | { | |
78 | 2 | throw new UnsupportedOperationException("EnvironmentConfiguration is read-only!"); |
79 | } | |
80 | ||
81 | /** | |
82 | * Removes all properties from this configuration. Because this | |
83 | * configuration is read-only, this operation is not allowed and will cause | |
84 | * an exception. | |
85 | */ | |
86 | @Override | |
87 | public void clear() | |
88 | { | |
89 | 1 | throw new UnsupportedOperationException("EnvironmentConfiguration is read-only!"); |
90 | } | |
91 | } |