Control of log4j occurs based on properties typically set in the log4j.properties file in the application classpath. You can change the log level of a given logger in this file. Note, however, that values may be overridden on the command line by specifying system properties (e.g. via "-Dlog4j..."). Note that "inheritance" of logger levels works such that (in our standard of qualified class name as the logger name) you can change a whole package's log level by specifying only a portion of the logger name. Note that you may commonly desire to enable ("global") debug logging on your local environment. To do this, you can simply change the line

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