Can a class be instantiated outside main() ?

[nirjari patel]

I am trying following code

import java.util.*;
import java.io.*;

public class CollectionEx{
	Hashtable t = new Hashtable();
		t.put("one", new Integer(1));
		t.put("two", new Integer(2));
		t.put("three", new Integer(3));
	Integer n = (Integer)t.get("one");
	if (n != null){
		System.out.println("one = " + n);
		}
}

I am getting 24 errors.

When I instantiate Hashtable in the main(), it compiles and runs.

So can we not instantiate a class outside main() ? If I dont have a main() in a class, then can I not instantiate any class in that class ?

If I can instantiate a class without main(), then why am I gettingerror in this class CollectionEx ?

Thanks

[fred rosenberger]

Generally, you don't create objects outside of METHODS - main or otherwise. So you CAN create objects outside of main, but inside some OTHER method.

[Paul Clapham]

You can also create objects outside any method if you do it as part of the declaration of an instance variable or a class variable. But code which isn't a declaration must be inside some method.

[Rob Spoor]

In the above code, only line 6 is allowed. It declares an instance variable with package-default access and initializes it immediately.

[David Newton]

It's not the instantiation that isn't allowed (line 5 :p) but everything else: a declaration with assignment is different than a statement; statements aren't allowed outside methods (and initializers, as they're sort of different).

[Rob Spoor]

David Newton wrote:(line 5 :p)

I'm using Opera which (rightfully!) doesn't ignore the line break directly after the [code] tag. Therefore there is one empty line at the start and the code declaration is at line 6.

(Of course Firefox and IE8 do ignore the line break so I'm a minority here...)