1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287
/* * @(#)Handler.java 1.21 06/04/07 * * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package java.util.logging; import java.io.UnsupportedEncodingException; /** * A <tt>Handler</tt> object takes log messages from a <tt>Logger</tt> and * exports them. It might for example, write them to a console * or write them to a file, or send them to a network logging service, * or forward them to an OS log, or whatever. * <p> * A <tt>Handler</tt> can be disabled by doing a <tt>setLevel(Level.OFF)</tt> * and can be re-enabled by doing a <tt>setLevel</tt> with an appropriate level. * <p> * <tt>Handler</tt> classes typically use <tt>LogManager</tt> properties to set * default values for the <tt>Handler</tt>'s <tt>Filter</tt>, <tt>Formatter</tt>, * and <tt>Level</tt>. See the specific documentation for each concrete * <tt>Handler</tt> class. * * * @version 1.21, 04/07/06 * @since 1.4 */ public abstract class Handler { private static final int offValue = Level.OFF.intValue(); private LogManager manager = LogManager.getLogManager(); private Filter filter; private Formatter formatter; private Level logLevel = Level.ALL; private ErrorManager errorManager = new ErrorManager(); private String encoding; // Package private support for security checking. When sealed // is true, we access check updates to the class. boolean sealed = true; /** * Default constructor. The resulting <tt>Handler</tt> has a log * level of <tt>Level.ALL</tt>, no <tt>Formatter</tt>, and no * <tt>Filter</tt>. A default <tt>ErrorManager</tt> instance is installed * as the <tt>ErrorManager</tt>. */ protected Handler() { } /** * Publish a <tt>LogRecord</tt>. * <p> * The logging request was made initially to a <tt>Logger</tt> object, * which initialized the <tt>LogRecord</tt> and forwarded it here. * <p> * The <tt>Handler</tt> is responsible for formatting the message, when and * if necessary. The formatting should include localization. * * @param record description of the log event. A null record is * silently ignored and is not published */ public abstract void publish(LogRecord record); /** * Flush any buffered output. */ public abstract void flush(); /** * Close the <tt>Handler</tt> and free all associated resources. * <p> * The close method will perform a <tt>flush</tt> and then close the * <tt>Handler</tt>. After close has been called this <tt>Handler</tt> * should no longer be used. Method calls may either be silently * ignored or may throw runtime exceptions. * * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. */ public abstract void close() throws SecurityException; /** * Set a <tt>Formatter</tt>. This <tt>Formatter</tt> will be used * to format <tt>LogRecords</tt> for this <tt>Handler</tt>. * <p> * Some <tt>Handlers</tt> may not use <tt>Formatters</tt>, in * which case the <tt>Formatter</tt> will be remembered, but not used. * <p> * @param newFormatter the <tt>Formatter</tt> to use (may not be null) * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. */ public void setFormatter(Formatter newFormatter) throws SecurityException { checkAccess(); // Check for a null pointer: newFormatter.getClass(); formatter = newFormatter; } /** * Return the <tt>Formatter</tt> for this <tt>Handler</tt>. * @return the <tt>Formatter</tt> (may be null). */ public Formatter getFormatter() { return formatter; } /** * Set the character encoding used by this <tt>Handler</tt>. * <p> * The encoding should be set before any <tt>LogRecords</tt> are written * to the <tt>Handler</tt>. * * @param encoding The name of a supported character encoding. * May be null, to indicate the default platform encoding. * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. * @exception UnsupportedEncodingException if the named encoding is * not supported. */ public void setEncoding(String encoding) throws SecurityException, java.io.UnsupportedEncodingException { checkAccess(); if (encoding != null) { try { if(!java.nio.charset.Charset.isSupported(encoding)) { throw new UnsupportedEncodingException(encoding); } } catch (java.nio.charset.IllegalCharsetNameException e) { throw new UnsupportedEncodingException(encoding); } } this.encoding = encoding; } /** * Return the character encoding for this <tt>Handler</tt>. * * @return The encoding name. May be null, which indicates the * default encoding should be used. */ public String getEncoding() { return encoding; } /** * Set a <tt>Filter</tt> to control output on this <tt>Handler</tt>. * <P> * For each call of <tt>publish</tt> the <tt>Handler</tt> will call * this <tt>Filter</tt> (if it is non-null) to check if the * <tt>LogRecord</tt> should be published or discarded. * * @param newFilter a <tt>Filter</tt> object (may be null) * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. */ public void setFilter(Filter newFilter) throws SecurityException { checkAccess(); filter = newFilter; } /** * Get the current <tt>Filter</tt> for this <tt>Handler</tt>. * * @return a <tt>Filter</tt> object (may be null) */ public Filter getFilter() { return filter; } /** * Define an ErrorManager for this Handler. * <p> * The ErrorManager's "error" method will be invoked if any * errors occur while using this Handler. * * @param em the new ErrorManager * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. */ public void setErrorManager(ErrorManager em) { checkAccess(); if (em == null) { throw new NullPointerException(); } errorManager = em; } /** * Retrieves the ErrorManager for this Handler. * * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. */ public ErrorManager getErrorManager() { checkAccess(); return errorManager; } /** * Protected convenience method to report an error to this Handler's * ErrorManager. Note that this method retrieves and uses the ErrorManager * without doing a security check. It can therefore be used in * environments where the caller may be non-privileged. * * @param msg a descriptive string (may be null) * @param ex an exception (may be null) * @param code an error code defined in ErrorManager */ protected void reportError(String msg, Exception ex, int code) { try { errorManager.error(msg, ex, code); } catch (Exception ex2) { System.err.println("Handler.reportError caught:"); ex2.printStackTrace(); } } /** * Set the log level specifying which message levels will be * logged by this <tt>Handler</tt>. Message levels lower than this * value will be discarded. * <p> * The intention is to allow developers to turn on voluminous * logging, but to limit the messages that are sent to certain * <tt>Handlers</tt>. * * @param newLevel the new value for the log level * @exception SecurityException if a security manager exists and if * the caller does not have <tt>LoggingPermission("control")</tt>. */ public synchronized void setLevel(Level newLevel) throws SecurityException { if (newLevel == null) { throw new NullPointerException(); } checkAccess(); logLevel = newLevel; } /** * Get the log level specifying which messages will be * logged by this <tt>Handler</tt>. Message levels lower * than this level will be discarded. * @return the level of messages being logged. */ public synchronized Level getLevel() { return logLevel; } /** * Check if this <tt>Handler</tt> would actually log a given <tt>LogRecord</tt>. * <p> * This method checks if the <tt>LogRecord</tt> has an appropriate * <tt>Level</tt> and whether it satisfies any <tt>Filter</tt>. It also * may make other <tt>Handler</tt> specific checks that might prevent a * handler from logging the <tt>LogRecord</tt>. It will return false if * the <tt>LogRecord</tt> is Null. * <p> * @param record a <tt>LogRecord</tt> * @return true if the <tt>LogRecord</tt> would be logged. * */ public boolean isLoggable(LogRecord record) { int levelValue = getLevel().intValue(); if (record.getLevel().intValue() < levelValue || levelValue == offValue) { return false; } Filter filter = getFilter(); if (filter == null) { return true; } return filter.isLoggable(record); } // Package-private support method for security checks. // If "sealed" is true, we check that the caller has // appropriate security privileges to update Handler // state and if not throw a SecurityException. void checkAccess() throws SecurityException { if (sealed) { manager.checkAccess(); } } }