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Why will TreeMap<K,V>(Comparator) not compile?

 
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The compiler won't let me do this:



It says:

mapc.java:13: cannot find symbol
symbol : constructor TreeMap(mapsortd)
location: class java.util.TreeMap<java.lang.Integer,mapc>
TreeMap<Integer,mapc> d = new TreeMap<Integer,mapc>(desc)
^



It seems TreeMap can use generics, or a Comparator, but not both. I don't quite see why the compiler would object to this. Can anyone explain this?
 
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TreeMap takes a Comparator that compares the keys -- not the values.

Henry
 
Thomas Kennedy
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Right, thank you!

TreeMap<Integer, mapx> m = new TreeMap<Integer,mapx>(new mapdesc());

class mapdesc implements Comparator<Integer>
 
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