Bug Report
https://issues.apache.org/bugzilla/show_bug.cgi?id=10528
Source Code
http://archive.apache.org/dist/logging/log4j/1.2.4/jakarta-log4j-1.2.4.tar.gz
EvoCrash Target Frame
2 and 3
java.lang.NullPointerException:
    at java.util.Hashtable.get(Hashtable.java:320)
    at org.apache.log4jb.MDC.get0(MDC.java:121)
    at org.apache.log4jb.MDC.get(MDC.java:75)
    at org.apache.log4jb.spi.LoggingEvent.getMDC(LoggingEvent.java:228)
    at org.apache.log4jb.helpers.PatternParser$MDCPatternConverter.convert(PatternParser.java:455)
    at org.apache.log4jb.helpers.PatternConverter.PatternConverter.java:56
    at org.apache.log4jb.PatternLayout.PatternLayout.java:495
    at org.apache.log4jb.WriterAppender.subAppend(WriterAppender.java:292)
    at org.apache.log4jb.RollingFileAppender.subAppend(RollingFileAppender.java:225)
    at org.apache.log4jb.WriterAppender.append(WriterAppender.java:150)
    at org.apache.log4jb.AppenderSkeleton.doAppend(AppenderSkeleton.java:221)
    at org.apache.log4jb.helpers.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:57)
    at org.apache.log4jb.Category.callAppenders(Category.java:190)
    at org.apache.log4jb.Category.forcedLog(Category.java:375)
    at org.apache.log4jb.Category.warn(Category.java:1024)
public void test0() throws Throwable {
    Object object0 = MDC.get((String) null);
    assertNull(object0);
}

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