skittles1412's blog

By skittles1412, history, 7 weeks ago, In English

Hello CodeForces,
due to the lack of a debugging template in Java (and really just any template in Java), I have decided to write my own template. To use it, add -DLOCAL to your custom VM Parameters. Note that you must use LOCAL = System.getProperty("ONLINE_JUDGE")==null; for CodeForces; this is not necessary for other OJs. Then call dbg(what you want to print) to print the "what you want to print" part to stderr.

To be more exact, when calling dbg(), It will print "Line #%d: [%s]" to stderr, where %d is the line number where you called dbg() and %s is the parameters, separated by commas. For each parameter, if it is able to be iterated using a for each loop (e.g. an array or some class implementing Iterable), it will be printed as {%s} where %s is each element printed, recursively, separated by commas. Otherwise, the .toString() method will be used.

Unfortunately, there is no way to get the names of the variables passed into the parameters of a method in Java, so I'd recommend calling dbg("variable_name", variable) to make it easier to read.

The code is not very clean (mainly due to the fact that arrays can't be cast to Iterable and because primitives can't be used in parametized methods). Please comment below if you have any suggestions or additions to the template (e.g. a class which this dbg method fails to print properly). I'll try to keep the code updated to the best of my ability.

Code

UPD:* Just realized that CodeForces doesn't allow you to query any property other than "ONLINE_JUDGE". I have accordingly updated the code and added a note.

 
 
 
 
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7 weeks ago, # |
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surprisingly underutilized

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7 weeks ago, # |
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Auto comment: topic has been updated by skittles1412 (previous revision, new revision, compare).

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6 weeks ago, # |
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Java is not my primary language, but wow, this seems like a great template! I appreciate this, given that many of the resources for debugging are written in C++.

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6 weeks ago, # |
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orz