BlackBird not support fluent setter

[wujimin]

Environment

• jdk 11
• jackson 2.12.0 with BlackBird

Reproduce case

define a model with fluent setter

public class BlackBirdBug {
  public static class Model {
      private int value = 10;

      public int getValue() {
          return value;
      }

      public Model setValue(int value) {
          this.value = value;

          return this;
      }
  }

  public static void main(String[] args) throws JsonProcessingException {
      ObjectMapper mapper = new ObjectMapper()
          .registerModule(new BlackbirdModule());
      String json = mapper.writeValueAsString(new Model());
      System.out.println(json);

      Model model = mapper.readValue(json, Model.class);
      System.out.println(model.getValue());
  }
}

will throw exception:

Caused by: java.lang.invoke.LambdaConversionException: Type mismatch for instantiated parameter 1: int is not a subtype of class java.lang.Object
	at [email protected]/java.lang.invoke.AbstractValidatingLambdaMetafactory.checkDescriptor(AbstractValidatingLambdaMetafactory.java:308)
	at [email protected]/java.lang.invoke.AbstractValidatingLambdaMetafactory.validateMetafactoryArgs(AbstractValidatingLambdaMetafactory.java:294)
	at [email protected]/java.lang.invoke.LambdaMetafactory.metafactory(LambdaMetafactory.java:328)
	at com.fasterxml.jackson.module.blackbird.deser.BBDeserializerModifier.createSetter(BBDeserializerModifier.java:221)
	at com.fasterxml.jackson.module.blackbird.deser.BBDeserializerModifier.nextProperty(BBDeserializerModifier.java:179)
	at com.fasterxml.jackson.module.blackbird.deser.BBDeserializerModifier.findOptimizableProperties(BBDeserializerModifier.java:126)
	... 14 more

we are trying switch from AfterBurner to BlackBird, because AfterBurner not support ToStringSerializer via @JsonSerialize in boolean oroperty

[cowtowncoder]

@wujimin Thank you for reporting this: I can reproduce the problem.

@stevenschlansker Looks like code might assume that all setters are of type void? I added a test under "..../failing" ( named BasicDeserialize123Test) and will see if I can see how this could be fixed, but if you have a chance to look at some point that'd be great as you know code much better :) .

[stevenschlansker]

That could be it, or maybe a spot where the VM would autobox for us but invokeExact doesn't. Either way I can take a look in the next few days (on vacation this week technically, happy new year all! )

[cowtowncoder]

@stevenschlansker yeah that sounds plausible. Return type is part of the signature, anyway. Could either filter out such cases (not optimize) or ideally handle, either would work.
Happy new year -- no rush obviously, I just added note as I had a chance to look at things reported for 2.12, before modest New Year's celebrations. :-)

[wujimin]

Happy new year

https://github.com/apache/servicecomb-java-chassis/blob/master/foundations/foundation-common/src/main/java/org/apache/servicecomb/foundation/common/utils/LambdaMetafactoryUtils.java#L131

commit: apache/servicecomb-java-chassis@d0655d7#diff-1bddb21d3057a94ecd88f453fd874a04f13dc1ae4b5093f6c1e9838fdb576246

We also had this problem most six months ago， and we just force set the return type to void to avoid the problem

[stevenschlansker]

Makes sense. Should be an easy enough fix.

[stevenschlansker]

@wujimin, it turned out to not be quite the same bug, but if you have a chance please verify that #124 fixes your issue

[wujimin]

@stevenschlansker
i have verified the new code
it fixed my issue.
thanks.

and find a new issue of https://github.com/FasterXML/jackson-modules-base/blob/2.12/blackbird/README.md

<dependency>
  <groupId>com.fasterxml.jackson.modules</groupId>
  <artifactId>jackson-module-blackbird</artifactId>
</dependency>

groupId should be com.fasterxml.jackson.module