to compare the memory usage between the use of the static array and java.util.ArrayList in a sorting operation -
runtime rt = runtime.getruntime(); long totalm = rt.totalmemory(); long currentm; int []n = new int[10000]; system.out.print("10000 ints used: "); system.out.println(totalm - rt.freememory());
its not working. cannot use long calculation?
thanks in advance, please give me suggestions
answering implicit question in title: difference in "memory usage between use of static array , java.util.arraylist in sorting operation".
in java 8: none. because sort delegated arraylist
class, sorts backing array directly using arrays.sort()
.
in java 7 , below, list converted array, array sorted, , result put list. so, memory doubled array, plus whatever memory need sorting operation itself, depends on version of java.
happens linkedlist
in java 8.
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