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Make PrintStream Faster

PrintStream is useful for outputting line-oriented data. However, the obvious constructor suffers from a potential performance problem: every call to print() is followed by an automatic flush. autoflushing prevents standard write buffering from providing its usual performance benefits, even if the stream given to the PrintStream is a buffered one, like BufferedOutputStream. When PrintStream is used as part of a batch processing application that outputs a large amount of data, this problem can cause output to be much slower than it needs to be.

The solution is simple: use the two-parameter constructor and pass false for the second parameter. That disables the autoflush behavior and lets write buffering speed up your output.

Last modified on 16 May 2001 by AO

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