001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache license, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the license for the specific language governing permissions and 015 * limitations under the license. 016 */ 017 package org.apache.logging.log4j.util; 018 019 import java.io.IOException; 020 import java.io.InputStream; 021 import java.net.URL; 022 import java.util.Enumeration; 023 import java.util.Properties; 024 025 import org.apache.logging.log4j.Logger; 026 import org.apache.logging.log4j.status.StatusLogger; 027 028 /** 029 * <em>Consider this class private.</em> 030 * <p> 031 * Helps access properties. This utility provides a method to override system properties by specifying properties 032 * in a properties file. 033 * </p> 034 */ 035 public final class PropertiesUtil { 036 037 private static final PropertiesUtil LOG4J_PROPERTIES = new PropertiesUtil("log4j2.component.properties"); 038 039 private static final Logger LOGGER = StatusLogger.getLogger(); 040 041 private final Properties props; 042 043 /** 044 * Constructs a PropertiesUtil using a given Properties object as its source of defined properties. 045 * 046 * @param props the Properties to use by default 047 */ 048 public PropertiesUtil(final Properties props) { 049 this.props = props; 050 } 051 052 /** 053 * Loads and closes the given property input stream. 054 * If an error occurs, log to the status logger. 055 * 056 * @param in 057 * a property input stream. 058 * @param source 059 * a source object describing the source, like a resource string 060 * or a URL. 061 * @return a new Properties object 062 */ 063 static Properties loadClose(final InputStream in, final Object source) { 064 final Properties props = new Properties(); 065 if (null != in) { 066 try { 067 props.load(in); 068 } catch (final IOException e) { 069 LOGGER.error("Unable to read {}", source, e); 070 } finally { 071 try { 072 in.close(); 073 } catch (final IOException e) { 074 LOGGER.error("Unable to close {}", source, e); 075 } 076 } 077 } 078 return props; 079 } 080 081 /** 082 * Constructs a PropertiesUtil for a given properties file name on the classpath. The properties specified in this 083 * file are used by default. If a property is not defined in this file, then the equivalent system property is 084 * used. 085 * 086 * @param propsLocn the location of properties file to load 087 */ 088 public PropertiesUtil(final String propsLocn) { 089 final ClassLoader loader = LoaderUtil.getThreadContextClassLoader(); 090 @SuppressWarnings("IOResourceOpenedButNotSafelyClosed") 091 final 092 Properties properties = new Properties(); 093 try { 094 final Enumeration<URL> enumeration = loader.getResources(propsLocn); 095 while (enumeration.hasMoreElements()) { 096 final URL url = enumeration.nextElement(); 097 final InputStream in = url.openStream(); 098 try { 099 properties.load(in); 100 } catch (final IOException ioe) { 101 LOGGER.error("Unable to read {}", url.toString()); 102 } finally { 103 try { 104 in.close(); 105 } catch (final IOException ioe) { 106 LOGGER.error("Unable to close {}", url.toString(), ioe); 107 } 108 } 109 110 } 111 112 } catch (final IOException ioe) { 113 LOGGER.error("Unable to access {}", propsLocn, ioe); 114 } 115 this.props = properties; 116 } 117 118 /** 119 * Returns the PropertiesUtil used by Log4j. 120 * 121 * @return the main Log4j PropertiesUtil instance. 122 */ 123 public static PropertiesUtil getProperties() { 124 return LOG4J_PROPERTIES; 125 } 126 127 /** 128 * Gets the named property as a String. 129 * 130 * @param name the name of the property to look up 131 * @return the String value of the property or {@code null} if undefined. 132 */ 133 public String getStringProperty(final String name) { 134 String prop = null; 135 try { 136 prop = System.getProperty(name); 137 } catch (final SecurityException ignored) { 138 // Ignore 139 } 140 return prop == null ? props.getProperty(name) : prop; 141 } 142 143 /** 144 * Gets the named property as an integer. 145 * 146 * @param name the name of the property to look up 147 * @param defaultValue the default value to use if the property is undefined 148 * @return the parsed integer value of the property or {@code defaultValue} if it was undefined or could not be 149 * parsed. 150 */ 151 public int getIntegerProperty(final String name, final int defaultValue) { 152 String prop = null; 153 try { 154 prop = System.getProperty(name); 155 } catch (final SecurityException ignored) { 156 // Ignore 157 } 158 if (prop == null) { 159 prop = props.getProperty(name); 160 } 161 if (prop != null) { 162 try { 163 return Integer.parseInt(prop); 164 } catch (final Exception ex) { 165 return defaultValue; 166 } 167 } 168 return defaultValue; 169 } 170 171 /** 172 * Gets the named property as a long. 173 * 174 * @param name the name of the property to look up 175 * @param defaultValue the default value to use if the property is undefined 176 * @return the parsed long value of the property or {@code defaultValue} if it was undefined or could not be 177 * parsed. 178 */ 179 public long getLongProperty(final String name, final long defaultValue) { 180 String prop = null; 181 try { 182 prop = System.getProperty(name); 183 } catch (final SecurityException ignored) { 184 // Ignore 185 } 186 if (prop == null) { 187 prop = props.getProperty(name); 188 } 189 if (prop != null) { 190 try { 191 return Long.parseLong(prop); 192 } catch (final Exception ex) { 193 return defaultValue; 194 } 195 } 196 return defaultValue; 197 } 198 199 /** 200 * Gets the named property as a String. 201 * 202 * @param name the name of the property to look up 203 * @param defaultValue the default value to use if the property is undefined 204 * @return the String value of the property or {@code defaultValue} if undefined. 205 */ 206 public String getStringProperty(final String name, final String defaultValue) { 207 final String prop = getStringProperty(name); 208 return (prop == null) ? defaultValue : prop; 209 } 210 211 /** 212 * Gets the named property as a boolean value. If the property matches the string {@code "true"} (case-insensitive), 213 * then it is returned as the boolean value {@code true}. Any other non-{@code null} text in the property is 214 * considered {@code false}. 215 * 216 * @param name the name of the property to look up 217 * @return the boolean value of the property or {@code false} if undefined. 218 */ 219 public boolean getBooleanProperty(final String name) { 220 return getBooleanProperty(name, false); 221 } 222 223 /** 224 * Gets the named property as a boolean value. 225 * 226 * @param name the name of the property to look up 227 * @param defaultValue the default value to use if the property is undefined 228 * @return the boolean value of the property or {@code defaultValue} if undefined. 229 */ 230 public boolean getBooleanProperty(final String name, final boolean defaultValue) { 231 final String prop = getStringProperty(name); 232 return (prop == null) ? defaultValue : "true".equalsIgnoreCase(prop); 233 } 234 235 /** 236 * Return the system properties or an empty Properties object if an error occurs. 237 * @return The system properties. 238 */ 239 public static Properties getSystemProperties() { 240 try { 241 return new Properties(System.getProperties()); 242 } catch (final SecurityException ex) { 243 LOGGER.error("Unable to access system properties.", ex); 244 // Sandboxed - can't read System Properties 245 return new Properties(); 246 } 247 } 248 }