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Optimizer can’t
do everything – you can help
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– |
Be aware of
overhead in some library routines
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Use newer
“collections” classes rather than older (Vector,
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Hashtable)
classes.
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Use profiler to
test your program’s performance
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Don’t
unnecessarily create objects
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Allocate
temporary objects outside loop and reuse them
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StringBuffer is
much more efficient than String for
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string
manipulation
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Use buffered IO
routines for reading data
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BufferedReader,
BufferedInputStream
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Use the java.nio
package when it becomes available
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Be wary of lists
like this one
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Many of them are
outdated by newer Java VM’s
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