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DataTable: Lazy getRowData Repeat the query twice

See original GitHub issue

1) Environment

PrimeFaces version: 8.0

org.joinfaces.primefaces-spring-boot-starter 4.3.0

2) Expected behavior

I hope that when I select a piece of data in the datatable, getRowData is executed only once.

3) Actual behavior

When I select a piece of data in the datatable, getRowData is executed twice, which is very strange.

AbstractLazyModel

    public abstract class AbstractLazyModel<T> {

    private T[] selects;
    private T select;

    private LazyDataModel<T> lazyDataModel;

    protected abstract LambdaQueryWrapper<T> getQueryParam();

    protected abstract BasicService getBasicService();

    protected  abstract String getKey(T t);


    public LazyDataModel<T> getResultModel() {
        if (lazyDataModel == null) {
            lazyDataModel = new LazyDataModel<T>() {
                @Override
                public List<T> load(int first, int pageSize, Map<String, SortMeta> sortMeta, Map<String, FilterMeta> filterMeta) {
                    int currentPage = (first / pageSize) + 1;
                    Page<T> page =  new Page(currentPage,pageSize);
                    page.setOptimizeCountSql(false);
                    return getBasicService().getResultList(page,getQueryParam());
                }

                @Override
                public T getRowData(String rowKey) {
                    return   (T)getBasicService().findById(rowKey);
                }

                @Override
                public String getRowKey(T t) {
                    return getKey(t);
                }
            };
            lazyDataModel.setRowCount( getBasicService().getRowCount(getQueryParam()));
        }
        return lazyDataModel;
    }

    protected void refresh() {
        this.setSelect(null);
        search();
    }

    public void search() {
        lazyDataModel = null;
    }

Example Bean

@Slf4j
@Data
@Component
@ViewScoped
public class ErpSysCodeTypeView extends AbstractLazyModel<ErpSysCodeType> implements java.io.Serializable {

    @Autowired
    private ErpSysCodeTypeService erpSysCodeTypeService;


    @Autowired
    private PrimeFaces primeFaces;

    @Autowired
    private FacesContext facesContext;

    private SysCodeTypeRequest sysCodeTypeRequest;

    private String codeName;


    private List<ErpSysCodeType> sysCodeTypeList;

    private ErpSysCodeType oldErpSysCodeType;


    public void searchListener() {
        this.refresh();
    }

    public void onRowSelect(SelectEvent<ErpSysCodeType> event) {
      // this.setSelect( event.getObject());
    }




    @PreDestroy
    public void destroy() {
        log.info("ErpSysCodeTypeView destroy");
    }


    @Override
    protected LambdaQueryWrapper<ErpSysCodeType> getQueryParam() {
        return new LambdaQueryWrapper<ErpSysCodeType>().
                likeRight(!StringUtils.isEmpty(codeName),ErpSysCodeType::getName,codeName);
    }


    @Override
    protected BasicService getBasicService() {
        return erpSysCodeTypeService;
    }

    @Override
    protected String getKey(ErpSysCodeType erpSysCodeType) {
        return String.valueOf(erpSysCodeType.getId());
    }

}

Example Xhtml

  <p:dataTable id="dataTableId"
                                         widgetVar="sysCodeTypeTableVar"
                                         value="#{erpSysCodeTypeView.resultModel}"
                                         paginatorPosition="bottom"
                                         rowIndexVar="rowIdx"
                                         rows="10"
                                         lazy="true"
                                         selection="#{erpSysCodeTypeView.select}"
                                         selectionMode="single"
                                         rowKey="#{_sysCodeType.id}"
                                         var="_sysCodeType"
                                         emptyMessage="暂无数据."
                                         paginator="true"
                                         currentPageReportTemplate="查询到{totalRecords}条记录，本页显示{startRecord}～{endRecord}；第{currentPage}/{totalPages}页"
                                         paginatorTemplate="{CurrentPageReport} {FirstPageLink} {PreviousPageLink} {PageLinks} {NextPageLink} {LastPageLink} {RowsPerPageDropdown}"
                                         rowsPerPageTemplate="5,10,15">

                                <p:ajax event="rowSelect"  listener="#{erpSysCodeTypeView.onRowSelect}" process="@this"/>

                                <p:column width="50">
                                    <f:facet name="header">序号</f:facet>
                                    <h:outputText value="#{rowIdx + 1}"/>
                                </p:column>

                                <p:column headerText="字典代码">
                                    <h:outputText value="#{_sysCodeType.code}"/>
                                </p:column>

                                <p:column headerText="字典名称">
                                    <h:outputText value="#{_sysCodeType.name}"/>
                                </p:column>

                                <p:column headerText="启用">
                                    <h:outputText value="#{_sysCodeType.status == 1 ? '启用':'关闭'}"/>
                                </p:column>

                                <p:column headerText="创建时间">
                                    <h:outputText value="#{_sysCodeType.createDate}">
                                        <f:convertDateTime pattern="yyyy-MM-dd HH::mm:ss"/>
                                    </h:outputText>
                                </p:column>

                            </p:dataTable>

Issue Analytics

State:
Created 3 years ago
Comments:29 (20 by maintainers)

Top GitHub Comments

1reaction

eric-5512commented, Aug 2, 2020

@eric-5512 Couldn’t you do something like this?

if (lazyDataModel == null) {
    lazyDataModel = new LazyDataModel < T > () {
        private T lastSelected = null;
        private String lastRowKey = null;

        @Override
        public List < T > load(int first, int pageSize, Map < String, SortMeta > sortMeta, Map < String, FilterMeta > filterMeta) {
            int currentPage = (first / pageSize) + 1;
            Page < T > page = new Page(currentPage, pageSize);
            page.setOptimizeCountSql(false);
            return getBasicService().getResultList(page, getQueryParam());
        }

        @Override
        public T getRowData(String rowKey) {
            if (lastRowKey.equals(rowKey)) {
                return lastSelected;
            } else {
                lastRowKey = rowKey;
                lastSelected = (T) getBasicService().findById(rowKey);
                return lastSelected;
            }
        }

        @Override
        public String getRowKey(T t) {
            return getKey(t);
        }
    };
    lazyDataModel.setRowCount(getBasicService().getRowCount(getQueryParam()));
}

@melloware No problem, it’s all right. But it’s strange. Thank you.

0reactions

Rapstercommented, Nov 28, 2020

I might have a solution for this