algorithm - Sorting list from smallest-largest-smallest in Java -

i'm trying sort set of data looks histogram of probability distribution function (i'm assuming distributed moment).

i have list of entries:

private static final class sortabledatasetentry{     number value;     comparable key;     public sortabledatasetentry(number value, comparable key){       this.value = value;       this.key = key;     } } 

an example: have items : {1,2,3,4,5,6,7,8,9}

edit: sorted list like: {1,3,5,7,9,8,6,4,2} (or similar) numbers not neat (i.e. sorting odd/even wont work either). have partial solution involves sorting regular order (lowest highest) copying list inserting middle each time, last item inserted (into middle) largest. i'd still find method of doing comparator.

this quite tricky because not being sorted absolute value of value distance mean(value) within set, , somehow moved values closest mean centered. know compareto function must "reversible" (i forget correct term).

bonus points: how determine correct distribution data (i.e. if isn't normal, assumed).

first calculate mean , store in variable called mean. next, when insert entries sortabledatasetentry, use value - mean actual value each entry rather value.