arrays - Java - Class Data Type - Sorting Problems -


assume have implemented class edge has 4 attributes, of of type int: from to quality length.

in program , have created edge[] array.

i want implement 2 sorting parameters -

one of them sort edge array in descending order of qualities,

the other sort based on increasing order of lengths.

i needing these 2 orderings in distinct parts of code.

i using library function arrays.sort() sorting.

the way know of sorting class data type arrays implement compareto() within class edge works 1 parameter(quality or length not both).

how can implement 2 sorting functions(2 compareto() functions ?) , decide 1 called during sorting? in c++ , can make many compare functions , state function go through.how achieve in java?

note: goal sort array of datatype edge using arrays.sort() , , use 2 different parameters sorting , decide 1 used @ point.

in java, can create 2 classes implements comparator, defining compare method, 1 each of sort orders desire.

then can pass instance of 1 of comparators arrays.sort.

if you're using java 8, can pass method reference comparator.comparing construct comparator based on getter method.

comparator<edge> lengthascedgecomp = comparator.comparing(edge::getlength);

to make descending sort, can call reversed.

comparator<edge> qualitydescedgecomp = comparator.comparing(edge::getquality).reversed();

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