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why I can't instance Math class?

 
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public class test
{
public static void main(String arg[])
{
Math m=new Math();
System.out.println("m.round="+m.round(100.00));
}
}

when compile the code ,the code give me a compile error:there isn't a construcor in class Math,but I look up in the jdk-doc,the Math is subclass of the class Object,the Object have a no-arg constructor : public Object()
,which mean that when instance the Math class,it will invoke the super class(Class)'s no-arg constructor : public Object().
If i am right about the question,how can I explain this.
 
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Yes, you are right about the Math class constructor invoking its superclass' (Object) constructor. However, Math's constructor is private so it cannot be instantiated from outside of the Math class itself. But then again, there is no need to instantiate Math because all of its methods are static. So really, the only reason that Math's constructor is there in the first place is so that it can be made private (otherwise, the compiler will provide a default public no-args constructor since Math is public).
In addition, Math is a final class so you cannot subclass it.

------------------
Junilu Lacar
Sun Certified Programmer for the Java� 2 Platform
 
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