java - Call constructor within constructor with self(this)-parameter -

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i need link object of type b instance of type (circular dependencies). declare method, must called after constructor of , link new b a-instance. want achieve not having call such method manually. sample code:

public class a{     b b;     public a(){         b = new b(this); // not work,                          // references object has not been created yet     } }  public class b{     a;     public b(a a){         this.a = a; //or else     } }

i commented problematic line. understand why can't work. need know is, if there well-known design pattern avoid problematic? or should redesign class model, putting in b a? suggestions?

it does work. it's problematic in exposes object before it's been initialized (so if b constructor calls methods on parameter, example, bad thing), work. reference b.a reference instance of a that's been/being constructed.

i recommend trying avoid cyclic reference possible, alternative worse, code you've given work.


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