Answer by ratchet freak for Should we avoid object creation in Java?

the GC is tuned for many short lived object

that said if you can trivially reduce object allocation you should

one example would be building a string in a loop, the naive way would be

String str = "";while(someCondition){    //...    str+= appendingString;}

which creates a new String object on each += operation (plus a StringBuilder and the new underlying char array)

you can easily rewrite this into:

StringBuilder strB = new StringBuilder();while(someCondition){    //...    strB.append(appendingString);}String str = strB.toString();

this pattern (immutable result and a local mutable intermediate value) can be applied to other things as well

but other than that you should pull up a profiler to find the real bottleneck instead of chasing ghosts