无法使用Jolt转换转换为以下格式的json

[
  {
    "operation": "shift",
    "spec": {
      "*": "&"
    }
  }
]

import com.bazaarvoice.jolt.Jolt;
import com.bazaarvoice.jolt.JsonUtils;

public class JoltExample {
    public static void main(String[] args) {
        String inputJson = "{\"name\":\"John\", \"age\":30}";
        String transformationSpec = "[{\"operation\": \"shift\", \"spec\": {\"name\": \"fullName\", \"age\": \"yearsOld\"}}]";

        try {
            Object input = JsonUtils.jsonToObject(inputJson);
            Object transformed = Jolt.transform(input, transformationSpec);
            String outputJson = JsonUtils.toJsonString(transformed);
            System.out.println(outputJson);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}