implementation - Implementing Java Comparator -

i trying write algorithm utilizes min-priority queue, looked around on google , found priorityqueue. seems in order use it, though, going need tell how want prioritize, , way comparator (i want compare specific data fields of "node1" objects). more googling presented idea of creating new comparator implements comparator overrides compare method. trying (and other variations of well):

import java.util.comparator;  public class distcomparator implements comparator {      @override     public int compare(node1 x, node1 y){         if(x.dist<y.dist){             return -1;         }         if(x.dist>y.dist){             return 1;         }         return 0;     } } 

the compiler protests on several grounds, 1 of haven't over-ridden comparator class (which says abstract)

error: distcomparator not abstract , not override abstract method compare(object,object) in comparator

i have switched "compare(object x, object y)", takes care of issue. @ point though compiler complains can't find "dist" variable in x or y--which makes sense, since part of node1 class, not object class.

so how supposed work? should have type object, apparently, how direct correct variable?

you need implement comparator<node1>:

public class distcomparator implements comparator<node1> {                                                  ^^^^^^^ 

without this, implementing comparator<object>, isn't want (it can made work, isn't worth hassle).

the rest of code in question fine, provided node1 has accessible member called dist.

note if using java 7, entire body of method can replaced with

return integer.compare(x.dist, y.dist); 

(replace integer double etc, depending on type of node1.dist.)