title: are Java properties files thread safe?
body: <p>There is a java application say App1 which creates a new log file for each run, the name of log file is dynamically set in run-time by configuring the log4j.properties file.<p>The jar of this java application(App1) is used by another application App2 which uses multithreading. Will each thread in App2 will have its own instance of log4j.properties file too, will it be thread safe to change log4j.properties in run-time?
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  sorry I could not come up with better title for my question, please edit if you think of somethink better</p>