Spring and returning large volume of Json data

Question

My project is based on Java 8 and uses Spring throughout I have a service that returns a bean which contains a list of beans in it.

Here is the code API Method

@RequestMapping(value = "/search",", produces = { MediaType.APPLICATION_JSON_VALUE }, method = RequestMethod.POST)
@ResponseBody
public DeferredResult<EmpAdvancedSearchPageBean> getSearch(
        @RequestBody final EmpBean empBean) {

    LOGGER.info("Pre getSearch");
    EmpSearchPageBean searchPageBean = dataService.getSearch(empBean);
    LOGGER.info("Post getSearch");

    LOGGER.info("Pre set deffered result");
    DeferredResult<EmpSearchPageBean> deferredResult = new DeferredResult<>();
    deferredResult.setResult(searchPageBean);
    LOGGER.info("Post set deffered result");

    return deferredResult;
}

EmpSearchPageBean

public class EmpSearchPageBean implements java.io.Serializable   {

    private static final long serialVersionUID = 8085664391632415982L;

    @JsonProperty("draw")
    private Integer draw;

    @JsonProperty("recordsTotal")
    private Integer recordsTotal;

    @JsonProperty("recordsFiltered")
    private Integer recordsFiltered;

    @JsonProperty("data")
    private List<EmpSearch> data;   
}   

EmpSearch

public class EmpSearch implements java.io.Serializable   {

    private static final long serialVersionUID = -7665557350420327753L;

    @JsonProperty("divisionDesc")
    private String divisionDesc;

    @JsonProperty("corpId")
    private String corpId;

    @JsonProperty("businessUnitDesc")
    private String businessUnitDesc;

    @JsonProperty("fdirName")
    private String fdirName;

}

If the list of data ( List data; ) contains 500 records - this service returns in about 2 seconds However if it contains around 2000 records (which is a common use case), it can take up to 2 minutes to return

Based on my log statements - it takes about 2 seconds to return this data from the database and the rest of the time is taken up producing the json.

I am using Spring Web version 4.3.3.RELEASE. from the debug logs I can see that it is using the class org.springframework.http.converter.json.MappingJackson2HttpMessageConverter

Can anyone offer any advise on what I need to do in order to render large quantities of json data successfully?

Answer 1

Decided to refactor code to not return as much json data. Tried multiple suggestions based on question feedback but did not get the required gains