How to implement constructor wrapping in Java? -

this i'm trying (in java 1.6):

public class foo {   public foo() {     bar b = new bar();     b.setsomedata();     b.dosomethingelse();     this(b);   }   public foo(bar b) {     // ...   } } 

compiler says:

call must first statement in constructor 

is there workaround?

you need implement this:

public class foo {   public foo() {     this(makebar());   }   public foo(bar b) {     // ...   }   private static bar makebar() {     bar b = new bar();     b.setsomedata();     b.dosomethingelse();     return b;   } } 

the makebar method should static, since object corresponding this not available @ point calling method.

by way, approach has advantage does pass initialized bar object foo(bar). (@ronu notes approach not. of course means foo(bar) constructor cannot assume foo argument in final state. can problematical.)

finally, agree static factory method alternative approach.