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java - Efficiency of creating new objects in a loop

I'm not certain if this question is language independent or not so I'm going to just ask this as a Java question. If you have a loop like

for (int i = 0; i < 9; i++) {
    Object obj = new Object;
    // fill object
    // do something with data
}

Is new space in memory being created through every iteration of the loop? If so, is the old space being disposed of? If not, is it more efficient to do something like this

Object obj = new Object;
for (int i = 0; i < 9; i++) {
    // fill object
    // do something with data
}

Edit: Updated code to better exemplify the question

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by (71.8m points)

Short answer: just ignore such things while developing in Java, even because most of these problems are black boxed and managed by the JVM itself.

The garbage collector will know what to do and it will try to do the best thing according to the situation.

In addition your specific examples don't make much sense to me.. could you elaborate it further?


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