Difference between initialising variables inside a loop and outside it.

What is the difference between initialising a variable, say a String, inside a loop and outside it?
Are there performance differences, memory allocation issues etc? Or is there no difference at all?
For example:
1. Outside the loop
String s = "";
while (foo)
s = some variable;
2. Inside the loop
while(foo)
String s = some variable;

.Hence, it definitely improves the performance of your code.That only depends on the code. Modern VM like Hotspot are very good at optimizing things.
for the in the loop thing.
Its true you need to create a new Object but memory doesnt need to be reallocated always because the VM knows the previiously declared Object has become available (it went out of scope)
Generaly: dont use the outside loop because you think it might help performance: always leave micro-optimizations for the VM.
It might be faster but its not a certantiy

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