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Diffstat (limited to 'libjava/java/util/logging/Formatter.java')
| -rw-r--r-- | libjava/java/util/logging/Formatter.java | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/libjava/java/util/logging/Formatter.java b/libjava/java/util/logging/Formatter.java new file mode 100644 index 0000000..c481969 --- /dev/null +++ b/libjava/java/util/logging/Formatter.java @@ -0,0 +1,174 @@ +/* Formatter.java + -- a class for formatting log messages by localizing message texts + and performing substitution of parameters + +Copyright (C) 2002 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA +02111-1307 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. + +*/ + + +package java.util.logging; + +import java.util.ResourceBundle; +import java.text.MessageFormat; + +/** + * A <code>Formatter</code> supports handlers by localizing + * message texts and by subsituting parameter values for their + * placeholders. + * + * @author Sascha Brawer (brawer@acm.org) + */ +public abstract class Formatter +{ + /** + * Constructs a new Formatter. + */ + protected Formatter() + { + } + + + /** + * Formats a LogRecord into a string. Usually called by handlers + * which need a string for a log record, for example to append + * a record to a log file or to transmit a record over the network. + * + * @param record the log record for which a string form is requested. + */ + public abstract String format(LogRecord record); + + + /** + * Returns a string that handlers are supposed to emit before + * the first log record. The base implementation returns an + * empty string, but subclasses such as {@link XMLFormatter} + * override this method in order to provide a suitable header. + * + * @return a string for the header. + * + * @param handler the handler which will prepend the returned + * string in front of the first log record. This method + * may inspect certain properties of the handler, for + * example its encoding, in order to construct the header. + */ + public String getHead(Handler handler) + { + return ""; + } + + + /** + * Returns a string that handlers are supposed to emit after + * the last log record. The base implementation returns an + * empty string, but subclasses such as {@link XMLFormatter} + * override this method in order to provide a suitable tail. + * + * @return a string for the header. + * + * @param handler the handler which will append the returned + * string after the last log record. This method + * may inspect certain properties of the handler + * in order to construct the tail. + */ + public String getTail(Handler handler) + { + return ""; + } + + + /** + * Formats the message part of a log record. + * + * <p>First, the Formatter localizes the record message to the + * default locale by looking up the message in the record's + * localization resource bundle. If this step fails because there + * is no resource bundle associated with the record, or because the + * record message is not a key in the bundle, the raw message is + * used instead. + * + * <p>Second, the Formatter substitutes appropriate strings for + * the message parameters. If the record returns a non-empty + * array for <code>getParameters()</code> and the localized + * message string contains the character sequence "{0", the + * formatter uses <code>java.text.MessageFormat</code> to format + * the message. Otherwise, no parameter substitution is performed. + * + * @param record the log record to be localized and formatted. + * + * @return the localized message text where parameters have been + * substituted by suitable strings. + * + * @throws NullPointerException if <code>record</code> + * is <code>null</code>. + */ + public String formatMessage(LogRecord record) + { + String msg; + ResourceBundle bundle; + Object[] params; + + /* This will throw a NullPointerExceptionif record is null. */ + msg = record.getMessage(); + if (msg == null) + msg = ""; + + /* Try to localize the message. */ + bundle = record.getResourceBundle(); + if (bundle != null) + { + try + { + msg = bundle.getString(msg); + } + catch (java.util.MissingResourceException _) + { + } + } + + /* Format the message if there are parameters. */ + params = record.getParameters(); + if ((params != null) + && (params.length > 0) + && (msg.indexOf("{0") >= 0)) + { + msg = MessageFormat.format(msg, params); + } + + return msg; + } +} |