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.text.lookup;
18
19 import java.util.Locale;
20
21 import org.apache.commons.lang3.StringUtils;
22 import org.apache.commons.text.StringSubstitutor;
23
24 /**
25 * Looks up keys related to Java: Java version, JRE version, VM version, and so on.
26 * <p>
27 * The lookup keys with examples are:
28 * </p>
29 * <ul>
30 * <li><strong>version</strong>: "Java version 1.8.0_181"</li>
31 * <li><strong>runtime</strong>: "Java(TM) SE Runtime Environment (build 1.8.0_181-b13) from Oracle Corporation"</li>
32 * <li><strong>vm</strong>: "Java HotSpot(TM) 64-Bit Server VM (build 25.181-b13, mixed mode)"</li>
33 * <li><strong>os</strong>: "Windows 10 10.0, architecture: amd64-64"</li>
34 * <li><strong>hardware</strong>: "processors: 4, architecture: amd64-64, instruction sets: amd64"</li>
35 * <li><strong>locale</strong>: "default locale: en_US, platform encoding: iso-8859-1"</li>
36 * </ul>
37 *
38 * <p>
39 * Using a {@link StringLookup} from the {@link StringLookupFactory}:
40 * </p>
41 *
42 * <pre>
43 * StringLookupFactory.INSTANCE.javaPlatformStringLookup().lookup("version");
44 * </pre>
45 * <p>
46 * Using a {@link StringSubstitutor}:
47 * </p>
48 *
49 * <pre>
50 * StringSubstitutor.createInterpolator().replace("... ${java:version} ..."));
51 * </pre>
52 * <p>
53 * The above examples convert {@code "version"} to the current VM version, for example,
54 * {@code "Java version 1.8.0_181"}.
55 * </p>
56 * <p>
57 * Public access is through {@link StringLookupFactory}.
58 * </p>
59 *
60 * @see StringLookupFactory
61 * @since 1.3
62 */
63 final class JavaPlatformStringLookup extends AbstractStringLookup {
64
65 /**
66 * Defines the singleton for this class.
67 */
68 static final JavaPlatformStringLookup INSTANCE = new JavaPlatformStringLookup();
69
70 /** {@code hardware} key for driving {@link JavaPlatformStringLookup#lookup(String)}. */
71 private static final String KEY_HARDWARE = "hardware";
72
73 /** {@code locale} key for driving {@link JavaPlatformStringLookup#lookup(String)}. */
74 private static final String KEY_LOCALE = "locale";
75
76 /** {@code os} key for driving {@link JavaPlatformStringLookup#lookup(String)}. */
77 private static final String KEY_OS = "os";
78
79 /** {@code runtime} key for driving {@link JavaPlatformStringLookup#lookup(String)}. */
80 private static final String KEY_RUNTIME = "runtime";
81
82 /** {@code version} key for driving {@link JavaPlatformStringLookup#lookup(String)}. */
83 private static final String KEY_VERSION = "version";
84
85 /** {@code vm} key for driving {@link JavaPlatformStringLookup#lookup(String)}. */
86 private static final String KEY_VM = "vm";
87
88 /**
89 * The main method for running the JavaPlatformStringLookup.
90 *
91 * @param args the standard Java main method parameter which is unused for our running of this class.
92 */
93 public static void main(final String[] args) {
94 System.out.println(JavaPlatformStringLookup.class);
95 System.out.printf("%s = %s%n", KEY_VERSION, INSTANCE.lookup(KEY_VERSION));
96 System.out.printf("%s = %s%n", KEY_RUNTIME, INSTANCE.lookup(KEY_RUNTIME));
97 System.out.printf("%s = %s%n", KEY_VM, INSTANCE.lookup(KEY_VM));
98 System.out.printf("%s = %s%n", KEY_OS, INSTANCE.lookup(KEY_OS));
99 System.out.printf("%s = %s%n", KEY_HARDWARE, INSTANCE.lookup(KEY_HARDWARE));
100 System.out.printf("%s = %s%n", KEY_LOCALE, INSTANCE.lookup(KEY_LOCALE));
101 }
102
103 /**
104 * No need to build instances for now.
105 */
106 private JavaPlatformStringLookup() {
107 // empty
108 }
109
110 /**
111 * Accessible through the Lookup key {@code hardware}.
112 *
113 * @return hardware processor information.
114 */
115 String getHardware() {
116 return "processors: " + Runtime.getRuntime().availableProcessors() + ", architecture: "
117 + getSystemProperty("os.arch") + this.getSystemProperty("-", "sun.arch.data.model")
118 + this.getSystemProperty(", instruction sets: ", "sun.cpu.isalist");
119 }
120
121 /**
122 * Accessible through the Lookup key {@code locale}.
123 *
124 * @return system locale and file encoding information.
125 */
126 String getLocale() {
127 return "default locale: " + Locale.getDefault() + ", platform encoding: " + getSystemProperty("file.encoding");
128 }
129
130 /**
131 * Accessible through the Lookup key {@code os}.
132 *
133 * @return operating system information.
134 */
135 String getOperatingSystem() {
136 return getSystemProperty("os.name") + " " + getSystemProperty("os.version")
137 + getSystemProperty(" ", "sun.os.patch.level") + ", architecture: " + getSystemProperty("os.arch")
138 + getSystemProperty("-", "sun.arch.data.model");
139 }
140
141 /**
142 * Accessible through the Lookup key {@code runtime}.
143 *
144 * @return Java Runtime Environment information.
145 */
146 String getRuntime() {
147 return getSystemProperty("java.runtime.name") + " (build " + getSystemProperty("java.runtime.version")
148 + ") from " + getSystemProperty("java.vendor");
149 }
150
151 /**
152 * Gets the given system property.
153 *
154 * @param name a system property name.
155 * @return a system property value.
156 */
157 private String getSystemProperty(final String name) {
158 return StringLookupFactory.INSTANCE_SYSTEM_PROPERTIES.apply(name);
159 }
160
161 /**
162 * Gets the given system property.
163 *
164 * @param prefix the prefix to use for the result string.
165 * @param name a system property name.
166 * @return The prefix + a system property value.
167 */
168 private String getSystemProperty(final String prefix, final String name) {
169 final String value = getSystemProperty(name);
170 if (StringUtils.isEmpty(value)) {
171 return StringUtils.EMPTY;
172 }
173 return prefix + value;
174 }
175
176 /**
177 * Accessible through the Lookup key {@code vm}.
178 *
179 * @return Java Virtual Machine information.
180 */
181 String getVirtualMachine() {
182 return getSystemProperty("java.vm.name") + " (build " + getSystemProperty("java.vm.version") + ", "
183 + getSystemProperty("java.vm.info") + ")";
184 }
185
186 /**
187 * Looks up the value of the Java platform key.
188 * <p>
189 * The lookup keys with examples are:
190 * </p>
191 * <ul>
192 * <li><strong>version</strong>: "Java version 1.8.0_181"</li>
193 * <li><strong>runtime</strong>: "Java(TM) SE Runtime Environment (build 1.8.0_181-b13) from Oracle Corporation"</li>
194 * <li><strong>vm</strong>: "Java HotSpot(TM) 64-Bit Server VM (build 25.181-b13, mixed mode)"</li>
195 * <li><strong>os</strong>: "Windows 10 10.0, architecture: amd64-64"</li>
196 * <li><strong>hardware</strong>: "processors: 4, architecture: amd64-64, instruction sets: amd64"</li>
197 * <li><strong>locale</strong>: "default locale: en_US, platform encoding: iso-8859-1"</li>
198 * </ul>
199 *
200 * @param key the key to be looked up, may be null.
201 * @return The value of the environment variable.
202 */
203 @Override
204 public String lookup(final String key) {
205 if (key == null) {
206 return null;
207 }
208 switch (key) {
209 case KEY_VERSION:
210 return "Java version " + getSystemProperty("java.version");
211 case KEY_RUNTIME:
212 return getRuntime();
213 case KEY_VM:
214 return getVirtualMachine();
215 case KEY_OS:
216 return getOperatingSystem();
217 case KEY_HARDWARE:
218 return getHardware();
219 case KEY_LOCALE:
220 return getLocale();
221 default:
222 throw new IllegalArgumentException(key);
223 }
224 }
225 }