Jackson Mapper并未映射所有字段

Question

I am using jackson to convert my POJO array to json, but it is not giving one particular field in the output, where as gson.toJson gives the output. can some one help?

public class TestCenter implements Comparable<TestCenter>{


    private Integer no_of_accessible_tests=0;
    private Integer tagId;
    private String tag;
    private Integer number_of_tests=0;

    private List<Test> tests= new ArrayList<>();

    public Integer getTagId() {
        return tagId;
    }
    public void setTagId(Integer tagId) {
        this.tagId = tagId;
    }
    public String getTag() {
        return tag;
    }
    public void setTag(String tag) {
        this.tag = tag;
    }
    public Integer getNumber_of_tests() {
        return number_of_tests;
    }
    public void setNumber_of_tests(Integer number_of_tests) {
        this.number_of_tests = number_of_tests;
    }
    public List<Test> getTests() {
        return tests;
    }
    public void setTests(List<Test> tests) {
        this.tests = tests;
    }

    public void addTest(Test t)
    {

        this.tests.add(t);
        this.number_of_tests++;
        if("Yes".equals(t.getAccess()))
            this.no_of_accessible_tests++;
    }
    @Override
    public int compareTo(TestCenter o) {

        if(this.no_of_accessible_tests.equals(o.no_of_accessible_tests))
        {
            return number_of_tests.compareTo(o.number_of_tests);
        }
        else
        {
            return o.no_of_accessible_tests.compareTo(this.no_of_accessible_tests);
        }
    }


}

System.out.println(gson.toJson(tests));
          System.out.println(mapper.writeValueAsString(tests));
          return mapper.writeValueAsString(tests);
output for both:
[{"no_of_accessible_tests":0,"tagId":196,"tag":"IBPS Clerical Prelims","number_of_tests":1,"tests":[{"activatedDate":null,"activatedTime":null,"ScheduleDate":null,"ScheduleTime":null,"endDate":null,"endTime":null,"testId":2193,"testCode":"P15 CP FLT 61","testName":"Amazon -4","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"start","testResult":null,"tags":["2017","IBPS Clerical Prelims"]}]},{"no_of_accessible_tests":0,"tagId":0,"tag":"Others","number_of_tests":6,"tests":[{"activatedDate":null,"activatedTime":null,"ScheduleDate":null,"ScheduleTime":null,"endDate":null,"endTime":null,"testId":2525,"testCode":"CP 16 FLT 04","testName":"Tech Mahindra -4","testType":"flt","testPattern":"ibps","testDurationInMinutes":65,"numberOfQuestions":76,"access":"No","status":"start","testResult":null,"tags":null},{"activatedDate":"2015-12-17","activatedTime":"09:00:00","ScheduleDate":"2015-12-17","ScheduleTime":"09:00:00","endDate":"license end date","endTime":"license end time","testId":2188,"testCode":"P15 CP FLT 58","testName":"Amazon -1","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"Resume","testResult":null,"tags":null},{"activatedDate":"2015-12-17","activatedTime":"09:00:00","ScheduleDate":"2015-12-17","ScheduleTime":"09:00:00","endDate":"license end date","endTime":"license end time","testId":2190,"testCode":"P15 CP FLT 59","testName":"Amazon -2","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"start","testResult":null,"tags":null},{"activatedDate":null,"activatedTime":null,"ScheduleDate":null,"ScheduleTime":null,"endDate":null,"endTime":null,"testId":2192,"testCode":"P15 CP FLT 60","testName":"Amazon -3","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"start","testResult":null,"tags":null},{"activatedDate":null,"activatedTime":null,"ScheduleDate":null,"ScheduleTime":null,"endDate":null,"endTime":null,"testId":1929,"testCode":"P15 CP FLT 09","testName":"CapGemini -1","testType":"flt","testPattern":"ibps","testDurationInMinutes":60,"numberOfQuestions":75,"access":"No","status":"start","testResult":null,"tags":null},{"test_ready":"no","reason_student_side":"This test would be available on 22-Dec-16.","reason_admin_side":".","testId":2633,"testCode":"BP FLT 87","testName":"SBI Specialist Officer Test -5","testType":"flt","testPattern":"ibps","testDurationInMinutes":90,"numberOfQuestions":120,"access":"No","status":"start","testResult":null,"tags":null}]}]
[{"tagId":196,"tag":"IBPS Clerical Prelims","number_of_tests":1,"tests":[{"testId":2193,"testCode":"P15 CP FLT 61","testName":"Amazon -4","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"start","testResult":null,"tags":["2017","IBPS Clerical Prelims"],"activatedDate":null,"activatedTime":null,"endDate":null,"endTime":null,"scheduleDate":null,"scheduleTime":null}]},{"tagId":0,"tag":"Others","number_of_tests":6,"tests":[{"testId":2525,"testCode":"CP 16 FLT 04","testName":"Tech Mahindra -4","testType":"flt","testPattern":"ibps","testDurationInMinutes":65,"numberOfQuestions":76,"access":"No","status":"start","testResult":null,"tags":null,"activatedDate":null,"activatedTime":null,"endDate":null,"endTime":null,"scheduleDate":null,"scheduleTime":null},{"testId":2188,"testCode":"P15 CP FLT 58","testName":"Amazon -1","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"Resume","testResult":null,"tags":null,"activatedDate":"2015-12-17","activatedTime":"09:00:00","endDate":"license end date","endTime":"license end time","scheduleDate":"2015-12-17","scheduleTime":"09:00:00"},{"testId":2190,"testCode":"P15 CP FLT 59","testName":"Amazon -2","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"start","testResult":null,"tags":null,"activatedDate":"2015-12-17","activatedTime":"09:00:00","endDate":"license end date","endTime":"license end time","scheduleDate":"2015-12-17","scheduleTime":"09:00:00"},{"testId":2192,"testCode":"P15 CP FLT 60","testName":"Amazon -3","testType":"flt","testPattern":"ibps","testDurationInMinutes":120,"numberOfQuestions":104,"access":"No","status":"start","testResult":null,"tags":null,"activatedDate":null,"activatedTime":null,"endDate":null,"endTime":null,"scheduleDate":null,"scheduleTime":null},{"testId":1929,"testCode":"P15 CP FLT 09","testName":"CapGemini -1","testType":"flt","testPattern":"ibps","testDurationInMinutes":60,"numberOfQuestions":75,"access":"No","status":"start","testResult":null,"tags":null,"activatedDate":null,"activatedTime":null,"endDate":null,"endTime":null,"scheduleDate":null,"scheduleTime":null},{"testId":2633,"testCode":"BP FLT 87","testName":"SBI Specialist Officer Test -5","testType":"flt","testPattern":"ibps","testDurationInMinutes":90,"numberOfQuestions":120,"access":"No","status":"start","testResult":null,"tags":null,"test_ready":"no","reason_student_side":"This test would be available on 22-Dec-16.","reason_admin_side":"."}]}]

it is not giving no_of_accessible_tests field in output

Answer 1

Thanks to @Scary Wombat. Seems the issue was there was no getter/setter for that field.