更新: 这不仅适用于AsyncAppender。也适用于控制台。
我面对AsyncAppender的奇怪行为,这种行为很少发生但有足够的伤害。
以下是代码段:
public void testNPE() {
try {
try {
throw new NullPointerException();
} catch (NullPointerException e) {
throw new RuntimeException(e);
}
} catch (RuntimeException e) {
logger.error("Catcha!" + e.getLocalizedMessage(), e);
}
}
可能的结果应该是:
07.12.12 10:21:34,904 ERROR [main] >> [com.ubs.eqdel.markitfeed.core.RetrieverTest:74] Catcha! java.lang.NullPointerException
java.lang.RuntimeException: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:71)
...
Caused by: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:69)
... 25 more
但是我看到20次尝试中的5次:
Exception in thread "Dispatcher-Thread-0" java.lang.NullPointerException
at java.io.Writer.write(Writer.java:140)
at org.apache.log4j.helpers.CountingQuietWriter.write(CountingQuietWriter.java:45)
at org.apache.log4j.WriterAppender.subAppend(WriterAppender.java:309)
at org.apache.log4j.RollingFileAppender.subAppend(RollingFileAppender.java:263)
at org.apache.log4j.WriterAppender.append(WriterAppender.java:160)
at org.apache.log4j.AppenderSkeleton.doAppend(AppenderSkeleton.java:251)
at org.apache.log4j.helpers.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:66)
at org.apache.log4j.AsyncAppender$Dispatcher.run(AsyncAppender.java:583)
at java.lang.T07.12.12 10:23:54,972 ERROR [main] >> [com.ubs.eqdel.markitfeed.core.RetrieverTest:74] Catcha! java.lang.NullPointerException
java.lang.RuntimeException: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:71)
...
Caused by: java.lang.NullPointerException
at com.ubs.eqdel.markitfeed.core.RetrieverTest.testNPE(RetrieverTest.java:69)
... 25 more
AsyncAppender出了什么问题?有人面对同样的事吗?这是什么解决方法?