java - Sorting text with some rules -


i have arraylist follows

100 aaa 500-1 lorem ipsum 100 bbb 500-2 lorem ipsum 101 aaa 500-1 lorem ipsum 101 aaa 500-2 lorem ipsum 100 bbb 500-3 lorem ipsum

i want sorted as

101 aaa 500-1 lorem ipsum 101 aaa 500-2 lorem ipsum 100 aaa 500-1 lorem ipsum 100 bbb 500-2 lorem ipsum 100 bbb 500-3 lorem ipsum

first, descending number (101, 100).

second, ascending 3 letter word (aaa, bbb).

third, ascending third column (500-1, 500-2, 500-3)

i can split each element space , individual word , sort. can please me other way or known algorithm? please let me know if need more information.

thank in advance.

creation of comparator solve problem. should implement this:

public class mycomparator implements comparator<myobject> {       public int compare(myobject o1, myobject o2) {     if (o1 == null || o2 == null) {       throw new nullpointerexception();     }         if (o1.getvalue1() != o2.getvalue1()) {       return integer.compare(o1.getvalue1(), o2.getvalue1());     }         return integer.compare(o1.getvalue2(), o2.getvalue2());   } }

of course there more ways solve problem, e.g., can implement own sorting algorithm. however, think use of comparator right "java-way" solve it.


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