| /* Formatter.java -- |
| A class for formatting log messages by localizing message texts |
| and performing substitution of parameters |
| Copyright (C) 2002, 2004 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., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 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.text.MessageFormat; |
| import java.util.ResourceBundle; |
| |
| /** |
| * 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; |
| } |
| } |