Doubt regarding overloaded method example

[Mansukhdeep Thind]

Hi

Following is an assignment question in SCJP for java 5 book:

class A{}  

class B extends A{}  
public class ComingThru{  
	static String s = "-";  
	public static void main (String [] args){  
		A[] aa = new A[2];  
		B[] ba = new B[2];  
		sifter(aa);  
		sifter(ba);  
		sifter(7);  
		System.out.println(s);  
	}

	static void sifter (A[]... a2){s+="1";}  
	static void sifter (B[]... b1){s+="2";}  
	static void sifter (B[] b1){s+="3";}  
	static void sifter (Object o){s+="4";}  

}  

The answer is -434

Can someone explain how ? In what order are the methods called and why?

[Campbell Ritchie]

Start by writing down very carefully what the four methods are, and what their parameters are (ie their signatures)..

[Mansukhdeep Thind]

Campbell Ritchie wrote:Start by writing down very carefully what the four methods are, and what their parameters are (ie their signatures)..

Got it sir. Arrays are objects too. hence the -434. Was a tricky one though..

[Campbell Ritchie]

Yes, an array is an object. The Foo[]... versions are equivalent to Foo[][] and you don’t have any arrays of arrays in that code.

[Mansukhdeep Thind]

Campbell Ritchie wrote:Yes, an array is an object. The Foo[]... versions are equivalent to Foo[][] and you don’t have any arrays of arrays in that code.

As borat says, HIGH 5!

[Campbell Ritchie]

Thank you