Re: [xwiki-devs] Logging facade (was Re: Hibernate 3.3.1 upgrade?)

Hi, Vincent Massol wrote: Ah, seeing this remembered me, that I wanted to introduce one of the slf4j features: delayed expanding of messages for logging see: http://n2.nabble.com/Logging-architecture-proposal-tt516791.html#none

I have done a small patch with this now (attachment). Or should I create a Jira issue?

An SLF4J Logger implementation is also very easy then. And I can use it ;). Greetings Jonas Index: core/xwiki-component/src/main/java/org/xwiki/component/ logging/Logger.java =================================================================== --- core/xwiki-component/src/main/java/org/xwiki/component/logging/ Logger.java (revision 12676) +++ core/xwiki-component/src/main/java/org/xwiki/component/logging/ Logger.java (working copy) @@ -39,17 +39,41 @@ void debug( String message ); + /** + * Logs the {@code message} to the logger while replacing all + * '{}' in the message String with the corresponding object + * from the objects array. Replacing first '{}' by + * {@code objects[0].toString()}, second '{}' by + * {@code objects[1].toString()} and so forth. + * </br> + * Ideally the message should only be expanded and thus the + * {@code toString()} be called iff the message is really logged. + * + * @param message The message to be formatted + * @param objects The objects to be filled into the message + */ + void debug( String message, Object... objects ); + void debug( String message, Throwable throwable ); boolean isDebugEnabled(); void info( String message ); + + /** + * @see Logger.debug(String, Object...) + * @param message + * @param objects + */ + void info( String message, Object... objects ); void info( String message, Throwable throwable ); boolean isInfoEnabled(); void warn( String message ); + + void warn( String message, Object... objects ); void warn( String message, Throwable throwable ); @@ -57,6 +81,8 @@ void error( String message ); + void error( String message, Object... objects ); + void error( String message, Throwable throwable ); boolean isErrorEnabled(); Index: core/xwiki-plexus/src/main/java/org/xwiki/plexus/logging/ PlexusLogger.java =================================================================== --- core/xwiki-plexus/src/main/java/org/xwiki/plexus/logging/ PlexusLogger.java (revision 12676) +++ core/xwiki-plexus/src/main/java/org/xwiki/plexus/logging/ PlexusLogger.java (working copy) @@ -26,6 +26,64 @@ { private org.codehaus.plexus.logging.Logger logger; + private static String expandMessage(String message, Object... objects){ + if(message == null) + return ""; + if(objects == null ) + return message; + int olast = objects.length - 1; + if(olast == -1) + return message; + + char[] msgchar = message.toCharArray(); + int mlast = msgchar.length - 1; + + StringBuffer sb = new StringBuffer(); + + int o = 0; + + // iterate through the Object Array and replace '{}' in the msg + for(int i = 0; i < mlast; i++) + { + if(msgchar[i] == '{' && msgchar[i+1] == '}') + { + i++; // the next one can be skipped + if( o < objects.length ) + { + if(objects[o] == null) + { + sb.append("(null)"); + } else { + sb.append(objects[o].toString()); + } + o++; + } + } else { + sb.append(msgchar[i]); + } + } + + // append last char only if it did not came from a '{}' + if( !(msgchar[mlast-1] == '{' && msgchar[mlast] == '}') ) + { + sb.append(msgchar[mlast]); + } + + if(objects[olast] instanceof Throwable) + { + Throwable e = (Throwable)objects[olast]; + sb.append("\n"); + for(StackTraceElement se : e.getStackTrace()) + { + sb.append(" "); + sb.append(se.toString()); + } + } + + return sb.toString(); + + } + public PlexusLogger(org.codehaus.plexus.logging.Logger logger) { this.logger = logger; @@ -36,6 +94,15 @@ this.logger.debug(message); } + public void debug(String message, Object... objects) + { + // only expand the message if the Debug level is enabled + if(this.logger.isDebugEnabled()) + { + this.logger.debug(expandMessage(message, objects)); + } + } + public void debug(String message, Throwable throwable) { this.logger.debug(message, throwable); @@ -50,6 +117,15 @@ { this.logger.info(message); } + + public void info(String message, Object... objects) + { + // only expand the message if the Info level is enabled + if(this.logger.isInfoEnabled()) + { + this.logger.info(expandMessage(message, objects)); + } + } public void info(String message, Throwable throwable) { @@ -65,6 +141,15 @@ { this.logger.warn(message); } + + public void warn(String message, Object... objects) + { + // only expand the message if the Warn level is enabled + if(this.logger.isWarnEnabled()) + { + this.logger.debug(expandMessage(message, objects)); + } + } public void warn(String message, Throwable throwable) { @@ -81,6 +166,15 @@ this.logger.error(message); } + public void error(String message, Object... objects) + { + // only expand the message if the Error level is enabled + if(this.logger.isErrorEnabled()) + { + this.logger.error(expandMessage(message, objects)); + } + } + public void error(String message, Throwable throwable) { this.logger.error(message, throwable);