StackOverFlow Exception przy użyciu stream i collect

forumPost.stream().map(Object::toString).collect(Collectors.joining(" || "));
Konsola:

SEVERE: Servlet.service() for servlet [dispatcher] in context with path [/CAndSource] threw exception [Handler dispatch failed; nested exception is java.lang.StackOverflowError] with root cause
java.lang.StackOverflowError
	at java.util.stream.Collectors$$Lambda$26/1552439843.<init>(Unknown Source)
	at java.util.stream.Collectors$$Lambda$26/1552439843.get$Lambda(Unknown Source)
	at java.util.stream.Collectors.joining(Unknown Source)
	at java.util.stream.Collectors.joining(Unknown Source)
	at com.cand.source.persistentce.Profile.toString(Profile.java:130)
	at java.lang.String.valueOf(Unknown Source)
	at java.lang.StringBuilder.append(Unknown Source)
	at com.cand.source.persistentce.ForumPost.toString(ForumPost.java:77)
	at java.util.stream.ReferencePipeline$3$1.accept(Unknown Source)
	at java.util.Iterator.forEachRemaining(Unknown Source)
	at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Unknown Source)
	at java.util.stream.AbstractPipeline.copyInto(Unknown Source)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(Unknown Source)
	at java.util.stream.AbstractPipeline.evaluate(Unknown Source)
	at java.util.stream.ReferencePipeline.collect(Unknown Source)
	at com.cand.source.persistentce.Profile.toString(Profile.java:130)
	at java.lang.String.valueOf(Unknown Source)
	at java.lang.StringBuilder.append(Unknown Source)
	at com.cand.source.persistentce.ForumPost.toString(ForumPost.java:77)
	at java.util.stream.ReferencePipeline$3$1.accept(Unknown Source)
	at java.util.Iterator.forEachRemaining(Unknown Source)
	at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Unknown Source)
	at java.util.stream.AbstractPipeline.copyInto(Unknown Source)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(Unknown Source)
	at java.util.stream.AbstractPipeline.evaluate(Unknown Source)
	at java.util.stream.ReferencePipeline.collect(Unknown Source)
	at com.cand.source.persistentce.Profile.toString(Profile.java:130)
	at java.lang.String.valueOf(Unknown Source)
	at java.lang.StringBuilder.append(Unknown Source)
	at com.cand.source.persistentce.ForumPost.toString(ForumPost.java:77)
	at java.util.stream.ReferencePipeline$3$1.accept(Unknown Source)
	at java.util.Iterator.forEachRemaining(Unknown Source)
	at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Unknown Source)
	at java.util.stream.AbstractPipeline.copyInto(Unknown Source)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(Unknown Source)
	at java.util.stream.AbstractPipeline.evaluate(Unknown Source)
	at java.util.stream.ReferencePipeline.collect(Unknown Source)
	at com.cand.source.persistentce.Profile.toString(Profile.java:130)
	

I tak w kółko... gdzieś się zapętla, mógłby ktoś mi powiedzieć dokładnie co? Chciałem złączyć wszystkie elementy z seta w stringa :)

Klasa1
{
Klasa2 klasa2;
toString(){
return "xxxx" + klasa2.toString();
}

Ja tam widze w stacktrace zapętlenie:
Profile toString woła ForumPost toString które woła Profile toString które woła...

Klasa1
{
   Klasa2 klasa2;

   toString(){
   return "xxxx" + klasa2.toString();
   }
}

Klasa2{
  Klasa1 klasa1;

  toString(){
   return klasa1.toString();
  }

}

Solved.. robiłem takie zapętlenie, poprzedni post wysłał się sam jakimś skrótem klawiszowym