Coding Tips
The following tips are only suggestions and may or may not give gains in performance, it
is to your own judgment and discretion to use them or not.
1. Use StringBuffer instead of String because of the fact the String object can not
be changed. Any modification to a String variable is actually a new object
creation.
2. Accessing class variables directly is faster then using setter and getter
methods
3. Using local variables are more efficient then instance/class variables
4. Using variables are more efficient then arrays.
5. Avoid synchronization in loops because there is an extra over head to lock and
unlock each time the loop occurs
6. Counting down in loops is faster then counting up
7. Use compound operators like x += 1 instead o f x = x + 1 because fewer byte
codes is generated
8. Remove constant calculations in loops
9. Reuse objects
10. Assign null to unused objects, especially unused threads
11. Try to use already built in methods, for example if you want to copy data from
one array to another use System.arraycopy more then likely this method will
be more efficient then the one you created yourself
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