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 package org.apache.logging.log4j.util;
18
19 import java.io.IOException;
20 import java.io.InputStream;
21 import java.net.URL;
22 import java.util.Properties;
23
24 import org.apache.logging.log4j.Logger;
25 import org.apache.logging.log4j.status.StatusLogger;
26
27 /**
28 * <em>Consider this class private.</em>
29 * <p>
30 * Helps access properties. This utility provides a method to override system properties by specifying properties
31 * in a properties file.
32 * </p>
33 */
34 public final class PropertiesUtil {
35
36 private static final PropertiesUtil LOG4J_PROPERTIES = new PropertiesUtil("log4j2.component.properties");
37
38 private static final Logger LOGGER = StatusLogger.getLogger();
39
40 private final Properties props;
41
42 /**
43 * Constructs a PropertiesUtil using a given Properties object as its source of defined properties.
44 *
45 * @param props the Properties to use by default
46 */
47 public PropertiesUtil(final Properties props) {
48 this.props = props;
49 }
50
51 /**
52 * Loads and closes the given property input stream.
53 * If an error occurs, log to the status logger.
54 *
55 * @param in
56 * a property input stream.
57 * @param source
58 * a source object describing the source, like a resource string
59 * or a URL.
60 * @return a new Properties object
61 */
62 static Properties loadClose(final InputStream in, final Object source) {
63 final Properties props = new Properties();
64 if (null != in) {
65 try {
66 props.load(in);
67 } catch (final IOException e) {
68 LOGGER.error("Unable to read {}", source, e);
69 } finally {
70 try {
71 in.close();
72 } catch (final IOException e) {
73 LOGGER.error("Unable to close {}", source, e);
74 }
75 }
76 }
77 return props;
78 }
79
80 /**
81 * Constructs a PropertiesUtil for a given properties file name on the classpath. The properties specified in this
82 * file are used by default. If a property is not defined in this file, then the equivalent system property is
83 * used.
84 *
85 * @param propertiesFileName the location of properties file to load
86 */
87 public PropertiesUtil(final String propertiesFileName) {
88 @SuppressWarnings("IOResourceOpenedButNotSafelyClosed")
89 final Properties properties = new Properties();
90 for (final URL url : LoaderUtil.findResources(propertiesFileName)) {
91 InputStream in = null;
92 try {
93 in = url.openStream();
94 properties.load(in);
95 } catch (final IOException ioe) {
96 LOGGER.error("Unable to read {}", url.toString(), ioe);
97 } finally {
98 if (in != null) {
99 try {
100 in.close();
101 } catch (final IOException ioe) {
102 LOGGER.error("Unable to close {}", url.toString(), ioe);
103 }
104 }
105 }
106 }
107 this.props = properties;
108 }
109
110 /**
111 * Returns the PropertiesUtil used by Log4j.
112 *
113 * @return the main Log4j PropertiesUtil instance.
114 */
115 public static PropertiesUtil getProperties() {
116 return LOG4J_PROPERTIES;
117 }
118
119 /**
120 * Gets the named property as a String.
121 *
122 * @param name the name of the property to look up
123 * @return the String value of the property or {@code null} if undefined.
124 */
125 public String getStringProperty(final String name) {
126 String prop = null;
127 try {
128 prop = System.getProperty(name);
129 } catch (final SecurityException ignored) {
130 // Ignore
131 }
132 return prop == null ? props.getProperty(name) : prop;
133 }
134
135 /**
136 * Gets the named property as an integer.
137 *
138 * @param name the name of the property to look up
139 * @param defaultValue the default value to use if the property is undefined
140 * @return the parsed integer value of the property or {@code defaultValue} if it was undefined or could not be
141 * parsed.
142 */
143 public int getIntegerProperty(final String name, final int defaultValue) {
144 String prop = null;
145 try {
146 prop = System.getProperty(name);
147 } catch (final SecurityException ignored) {
148 // Ignore
149 }
150 if (prop == null) {
151 prop = props.getProperty(name);
152 }
153 if (prop != null) {
154 try {
155 return Integer.parseInt(prop);
156 } catch (final Exception ignored) {
157 return defaultValue;
158 }
159 }
160 return defaultValue;
161 }
162
163 /**
164 * Gets the named property as a long.
165 *
166 * @param name the name of the property to look up
167 * @param defaultValue the default value to use if the property is undefined
168 * @return the parsed long value of the property or {@code defaultValue} if it was undefined or could not be
169 * parsed.
170 */
171 public long getLongProperty(final String name, final long defaultValue) {
172 String prop = null;
173 try {
174 prop = System.getProperty(name);
175 } catch (final SecurityException ignored) {
176 // Ignore
177 }
178 if (prop == null) {
179 prop = props.getProperty(name);
180 }
181 if (prop != null) {
182 try {
183 return Long.parseLong(prop);
184 } catch (final Exception ignored) {
185 return defaultValue;
186 }
187 }
188 return defaultValue;
189 }
190
191 /**
192 * Gets the named property as a String.
193 *
194 * @param name the name of the property to look up
195 * @param defaultValue the default value to use if the property is undefined
196 * @return the String value of the property or {@code defaultValue} if undefined.
197 */
198 public String getStringProperty(final String name, final String defaultValue) {
199 final String prop = getStringProperty(name);
200 return (prop == null) ? defaultValue : prop;
201 }
202
203 /**
204 * Gets the named property as a boolean value. If the property matches the string {@code "true"} (case-insensitive),
205 * then it is returned as the boolean value {@code true}. Any other non-{@code null} text in the property is
206 * considered {@code false}.
207 *
208 * @param name the name of the property to look up
209 * @return the boolean value of the property or {@code false} if undefined.
210 */
211 public boolean getBooleanProperty(final String name) {
212 return getBooleanProperty(name, false);
213 }
214
215 /**
216 * Gets the named property as a boolean value.
217 *
218 * @param name the name of the property to look up
219 * @param defaultValue the default value to use if the property is undefined
220 * @return the boolean value of the property or {@code defaultValue} if undefined.
221 */
222 public boolean getBooleanProperty(final String name, final boolean defaultValue) {
223 final String prop = getStringProperty(name);
224 return (prop == null) ? defaultValue : "true".equalsIgnoreCase(prop);
225 }
226
227 /**
228 * Return the system properties or an empty Properties object if an error occurs.
229 * @return The system properties.
230 */
231 public static Properties getSystemProperties() {
232 try {
233 return new Properties(System.getProperties());
234 } catch (final SecurityException ex) {
235 LOGGER.error("Unable to access system properties.", ex);
236 // Sandboxed - can't read System Properties
237 return new Properties();
238 }
239 }
240 }