StackOverflowError

package com.example.foo;

import java.util.AbstractMap.SimpleImmutableEntry;
import java.util.Map.Entry;

public class SomeClass {

  public static void main(final String[] args) {

    class Ref {
      Object value;

      @Override
      public String toString() {
        try {
          return this.value.toString();
        } catch (final StackOverflowError e) {
          return "...";
        }
      }
    }
    Entry<Ref, Ref> entry;
    final Ref ar1 = new Ref();
    final Ref ar2 = new Ref();
    entry = new SimpleImmutableEntry<>(ar1, ar2);
    ar1.value = entry;
    ar2.value = ar1;
    // Object-graph contains loop:
    // Entry[key=Entry, value=key]
    try {
      System.out.println(entry.toString());
    } catch (final Throwable e) {
      e.printStackTrace();
    }
  }
}