Bug Report
https://issues.apache.org/bugzilla/show_bug.cgi?id=509
Source Code
http://archive.apache.org/dist/logging/log4j/1.0.4/jakarta-log4j-1.0.4.tar.gz
EvoCrash Target Frame
1 and 2
java.lang.NullPointerException:
    at org.apache.log4jb.FileAppender.subAppend(FileAppender.java:442)
    at org.apache.log4jb.RollingFileAppender.subAppend(RollingFileAppender.java:260)
    at org.apache.log4jb.FileAppender.append(FileAppender.java:220)
    at org.apache.log4jb.AppenderSkeleton.doAppend(AppenderSkeleton.java:221)
    at org.apache.log4jb.helpers.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:56)
    at org.apache.log4jb.Category.callAppenders(Category.java:258)
    at org.apache.log4jb.Category.forcedLog(Category.java:454)
    at org.apache.log4jb.Category.debug(Category.java:315)
public void test0() throws Throwable {
    SimpleLayout simpleLayout0 = new SimpleLayout();
    DefaultCategoryFactory defaultCategoryFactory0 = new DefaultCategoryFactory();
    Category category0 = defaultCategoryFactory0.makeNewCategoryInstance("{>=40V");
    Priority priority0 = Priority.toPriority("e}t6vei!,q8x=40V", category0, priority0, "ERROQ", (Throwable) mockThrowable0);
    BufferedOutputStream bufferedOutputStream0 = new BufferedOutputStream((OutputStream) null);
    FileAppender fileAppender0 = new FileAppender((Layout) simpleLayout0, (OutputStream) bufferedOutputStream0);
    fileAppender0.subAppend(loggingEvent0);
}

public void test1() throws Throwable {
    HTMLLayout hTMLLayout0 = new HTMLLayout();
    DataOutputStream dataOutputStream0 = new DataOutputStream((OutputStream) null);
    RollingFileAppender rollingFileAppender0 = new RollingFileAppender((Layout) hTMLLayout0, (OutputStream) dataOutputStream0);
    Category category0 = Category.getInstance("K>Rf@~d3rJ.RuJ&4rqK");
    Priority priority0 = Priority.toPriority(2110);
    MockThrowable mockThrowable0 = new MockThrowable("MaxBackupIndex");
    LoggingEvent loggingEvent0 = new LoggingEvent((String) null, category0, priority0, "0", (Throwable) mockThrowable0);
    rollingFileAppender0.subAppend(loggingEvent0);
}

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