excel - How to store cell positions(row,column) in Java? -

i've store cell positions in excel file compared later. ex. (1,6) (1,17) (2,6) (2,17). 1 -> row, 6 -> column

i can't figure out collection use in java this.

there must mapping present between 2 values. can't use map because key values not unique. don't want use multidimensional arrays complicated.

any suggestions welcome.

if need map single row value multiple column values, use map<integer, list<integer>> or map<integer, set<integer>>, , create kind of adjacency list. then, having row value, able retrieve corresponding column values. make easier use, wrap custom class this:

class positions {     private map<integer, set<integer>> positions = new hashmap<>();      void add(int row, int column) {         set<integer> columns = this.columnsfromrow(row);         columns.add(column);         this.positions.put(row, columns);     }      set<integer> columnsfromrow(int row) {         set<integer> columns = this.positions.get(row);         if (columns == null) {             columns = new hashset<>();         }         return columns;     }      boolean isthereposition(int row, int column) {         return this.columnsfromrow(row).contains(column);     } }