JacksonStackoverflowTest.java

import java.util.ArrayList;
import java.util.List;

import org.apache.commons.lang3.tuple.ImmutablePair;
import org.apache.commons.lang3.tuple.Pair;
import org.junit.Test;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonStackoverflowTest {

  private final ObjectMapper mapper = new ObjectMapper();
  
  @Test
  public void shouldNotStackOverflow() throws JsonProcessingException {
    List<Pair<String, Double>> list = new ArrayList<>();
    list.add(ImmutablePair.of("Hello World!", 123d));
    // Throws StackOverflow error
    mapper.writeValueAsString(list);
  }
}

The following JUnit shows that Jackson 2.6.2 cannot serialize properly a List<Pair<String, Double>>.

Is it possible to reproduce this without external dependencies (Commons-lang in this case)?

Difference between 2.5 and 2.6 sounds strange, as there should not be difference in type handling.

I tried to reproduce with hand-made ImmutablePair and i could not reproduce it yet. There is something with the abstract or interfaces implemented in commons-lang3 which messes up the serialization.

Were you able to run this junit on your side? Anyway, it works fine with 2.5.4.