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Regular Expression to Replace System.out.println with Log4j

This is nothing fancy, but may help some of you log4j newbies.

I found myself replacing a project's hideous System.out.println statements with log4j log calls.

Just do a File Search in eclipse , tick the regular expression box and do a Replace:

Find: System\.out\.println$"(.+?)"$;
Replace: log.info("\1");

Now you just have to go in and add your imports and your log field variable to your classes.

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2 Comments

Bill
October 8th, 2009 at 12:22 pm

Nice idea, but it does not account for the all to common case of:
System.out.println(myClassName + "my quoted text" +
myVar1 +
myVar2 +
myVarN);

So I tried this:
System\.out\.println$(.+\R?){0,5}$;$

which works fine... you ask why the {0,5}? because eclipse seems to choke on the greedier '+' implementation. Perhaps a limitation in Eclipse.
Nils
December 6th, 2010 at 8:37 pm

Why don't you just replace "System.out.println" with "logger.info"?