[LOG4J2-180] style & highlight patterns altering content behaviour

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 2.0-beta4
• Component/s: Layouts
• Assignee: Unassigned
• Reporter: Seyguai
• Created: 21/Mar/13 16:47
• Updated: 24/Aug/13 11:48

Description

• Using style or highlight patterns over a Throwable pattern makes this code useless if the exception is the only content (i.e. "%highlight {%ex}

  ")

  org.apache.logging.log4j.core.pattern.ThrowablePatternConverter:format(final LogEvent event, final StringBuilder toAppendTo) {
  ...
              final int len = toAppendTo.length();
              if (len > 0 && !Character.isWhitespace(toAppendTo.charAt(len - 1))) {
                  toAppendTo.append(" "); // Add a space before printing stack trace
              }
  ...
  }
  

  (With style or highlight patterns, the format is called with a new empty StringBuilder)

Example:

17:26:54.395 ERROR # Server.doOperation catchingjava.lang.NullPointerException

(Syntax affected, no space between the message 'catching' and the exception 'java.lang.NullPointerException')

• Using style or highlight patterns over a Throwable pattern makes it to be duplicated (the pattern is interpreted as if there was nothing dealing with throwables)

Examples:

Simple pattern: "%m %ex{short}"
Output: catching java.lang.NullPointerException
        at net.wm.core.prototype.Server.doOperation(Server.java:27)

Pattern with highlight: "%m %highlight{%ex{short}}"
Output: catching java.lang.NullPointerException
        at net.wm.core.prototype.Server.doOperation(Server.java:27)
 java.lang.NullPointerException
        at net.wm.core.prototype.Server.doOperation(Server.java:27) [bin/:?]
        at net.wm.core.AbstractOperation.run(AbstractOperation.java:99) [bin/:?]
        at java.lang.Thread.run(Unknown Source) [?:1.7.0_07]

Issue Links

• relates to: LOG4J2-319 Double stack trace logging when using %throwable in %style and %highlight