Java enums over Constants -

possible duplicate:
understanding enums in java

why should use enums rather java constants?

i have read java enums gives type safety. can please elaborate it? or there other advantage of using enum on constants?

to quote http://docs.oracle.com/javase/tutorial/java/javaoo/enum.html:

public enum day {     sunday, monday, tuesday, wednesday,     thursday, friday, saturday  } 

when have method:

public enumtest(day day) {     this.day = day; } 

you know argument going day.

compare this:

const int monday = 1; const int tuesday = 2;  const int cat = 100; const int dog = 101; 

you pass anything method:

public enumtest(int day) {     this.day = day; } 

using enum (or type, such class or interface) gives type safety: type system makes sure can kind of type want. second example not type safe in regard, because method int argument, , don't know sure int value means.

using enum contract between calling code , code being called given value of given type.