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ASF GitHub Bot logged work on LOG4J2-2211: ------------------------------------------ Author: ASF GitHub Bot Created on: 16/Feb/20 07:45 Start Date: 16/Feb/20 07:45 Worklog Time Spent: 10m Work Description: rgoers commented on pull request #144: [LOG4J2-2211] Update StrSubstitutor.java URL: https://github.com/apache/logging-log4j2/pull/144 ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org Issue Time Tracking ------------------- Worklog Id: (was: 388044) Time Spent: 1h (was: 50m) > MainMapLookup ${main:--file} placeholder doesn't work > ----------------------------------------------------- > > Key: LOG4J2-2211 > URL: https://issues.apache.org/jira/browse/LOG4J2-2211 > Project: Log4j 2 > Issue Type: Bug > Components: Lookups > Affects Versions: 2.10.0 > Environment: java: 1.7 > log4j: 2.10.0 > os : windows > Reporter: wangzhongkuo > Priority: Blocker > Labels: newbie > Fix For: 2.13.1 > > Time Spent: 1h > Remaining Estimate: 0h > > I use the MainMapLookup like the > documentation([http://logging.apache.org/log4j/2.x/manual/lookups.html#AppMainArgsLookup),b|http://logging.apache.org/log4j/2.x/manual/lookups.html#AppMainArgsLookup),i]ut > the "${main:–file}" doesn't work, it replace the placeholder by default > value "-file". > log4j2.xml(log4j2 2.10.0) > > {code:java} > <?xml version="1.0" encoding="UTF-8"?> > <Configuration status="INFO"> > <Appenders> > <Console name="Console" target="SYSTEM_OUT"> > <PatternLayout > pattern="%d [%t] [${main:--file}] %-5level: %msg%n%throwable" /> > </Console> > </Appenders> > <Loggers> > <Logger name="org.foo" level="DEBUG" /> > <Root level="TRACE"> > <AppenderRef ref="Console" /> > </Root> > </Loggers> > </Configuration> > {code} > im sure i have written the code: MainMapLookup.setMainArguments(args); > > my program arguments are : --file foo.txt --verbose -x bar > so i traced the source code, in StrSubstitutor.class line 958, it changes my > varName "main:–file" to "main". i can't understand the code : "varName = > varNameExpr.substring(0, i);" > {code:java} > if (valueDelimiterMatcher != null) { > final char [] varNameExprChars = varNameExpr.toCharArray(); > int valueDelimiterMatchLen = 0; > for (int i = 0; i < varNameExprChars.length; i++) { > // if there's any nested variable when nested variable substitution disabled, > then stop resolving name and default value. > if (!substitutionInVariablesEnabled > && prefixMatcher.isMatch(varNameExprChars, i, i, varNameExprChars.length) != > 0) { > break; > } > if ((valueDelimiterMatchLen = valueDelimiterMatcher.isMatch(varNameExprChars, > i)) != 0) { > varName = varNameExpr.substring(0, i); > varDefaultValue = varNameExpr.substring(i + valueDelimiterMatchLen); > break; > } > } > } > {code} > then org.apache.logging.log4j.core.lookup.Interpolator.class > > {code:java} > @Override > public String lookup(final LogEvent event, String var) { > if (var == null) { > return null; > } > final int prefixPos = var.indexOf(PREFIX_SEPARATOR); > if (prefixPos >= 0) { > final String prefix = var.substring(0, prefixPos).toLowerCase(Locale.US); > final String name = var.substring(prefixPos + 1); > final StrLookup lookup = lookups.get(prefix); > if (lookup instanceof ConfigurationAware) { > ((ConfigurationAware) lookup).setConfiguration(configuration); > } > String value = null; > if (lookup != null) { > value = event == null ? lookup.lookup(name) : lookup.lookup(event, name); > } > if (value != null) { > return value; > } > var = var.substring(prefixPos + 1); > } > if (defaultLookup != null) { > return event == null ? defaultLookup.lookup(var) : > defaultLookup.lookup(event, var); > } > return null; > } > {code} > in the red mark, var="main" and prefixPos=-1. so it return the default value > "-file"; > > -- This message was sent by Atlassian Jira (v8.3.4#803005)