Issue with Primefaces p:dataExporter, which exports a DataTable with SelectOneMenu not as expected?

问题

I want to Export the <p:dataTable> which has a SelectOneMenu as shown in this Example JSF Primefaces SelectOneMenu

So, i used the primefaces <p:dataExporter type="xls" target="datatbleId" fileName="cars"/>

which generated a xls file as the below format:

------------------------------------
Name | Car 
----------------------------------------
ABC | 1
DDD | 2

What should i do ? So, that i can generate a xls in the below format :

------------------------------------
Name | Car 
----------------------------------------
ABC | Toyota
DDD | Ford

My DataTable Code Looks like this:

<p:dataTable id="studentDtble" var="studentDetail" value="#{studentController.studentList}" emptyMessage="No records found">
    <p:column styleClass="ralign">
        <f:facet name="header">
            <h:outputText value="Student Id " />
        </f:facet>
        <p:commandLink id="studentCmdLnk" action="#{profileHandler.showStudentProfile}" update=":tabView:loanOvrviewForm">
            <h:outputText id="studentIdOutTxt" value="#{studentDetail.studentId}" />
        </p:commandLink>
    </p:column>
    <p:column>
        <f:facet name="header">
            <h:outputText value="Class" />
        </f:facet>
        <h:outputText id="classoutTxt" value="#{studentDetail.class}" />
    </p:column>
    <p:column>
        <f:facet name="header">
            <h:outputText value="Student Name" />
        </f:facet>
        <h:outputText id="nameoutTxt" value="#{studentDetail.studentName}" />
    </p:column>
    <p:column>
        <f:facet name="header">
            <h:outputText value="Contact No" />
        </f:facet>
        <h:inputText id="contactInTxt" value="#{studentDetail.studentContact}" />
    </p:column>
    <p:column>
        <f:facet name="header">
            <h:outputText value="DOJ" />
        </f:facet>
        <h:outputText id="dojDateOutTxt" value="#{studentDetail.dojDate}">
            <f:convertDateTime pattern="MM/dd/yyyy" />
        </h:outputText>
    </p:column>
    <p:column>
        <f:facet name="header">
            <h:outputText value="Group/Branch" />
        </f:facet>
        <p:selectOneMenu id="branchesLstBox" value="#{studentDetail.branchList.branchId}">
            <f:selectItems value="#{studentController.getAllBranches()}" var="branches" itemValue="#{branches.branchId}" itemLabel="#{branches.branchName}" />
        </p:selectOneMenu>
    </p:column>
    <p:column>
        <f:facet name="header">
            <h:outputText value="Remarks" />
        </f:facet>
        <p:inputText id="remarksInTxt" value="#{studentDetail.remarks}" />
    </p:column>

</p:dataTable>

回答1:

I'm not sure you can do it with dataExporter, however you can implement your own exporter, it's quite easy, you just need Apache POI.

Sample :

A button to put in the facelet.

<p:commandButton icon="ui-icon-arrowstop-1-s" value="XLS" onclick="PrimeFaces.monitorDownload(start, stop)">
<p:fileDownload  value="#{dataExporter.generateXLS()}" />                       
</p:commandButton >

A request scoped managed bean (but you can implement a webservlet too)

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLConnection;
import java.util.List;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;

import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.primefaces.model.DefaultStreamedContent;
import org.primefaces.model.StreamedContent;

@ManagedBean(name="dataExporter")
@RequestScoped
public class DataExporter  {

 public StreamedContent generateXLS() {

        if (list != null) { // the list you are using in the data Table
            if (!list.isEmpty()) {
                String filePath = "E:\\tmp\\";
                String fileName = "xlsFile";
                String a = filePath + fileName;
                XSSFWorkbook new_workbook = new XSSFWorkbook(); 
                XSSFSheet sheet = new_workbook.createSheet("SAMPLE"); 
                int cellnum = 0;
                int rownum = 0 ;
                Row row = sheet.createRow(0);

                 for (Object object : list) { //loop through the data and add them to the cell
                    row = sheet.createRow(rownum++);
                    cellnum = 0;

                    cell = row.createCell(cellnum++);
                    if (object.getColumn1() == null) {
                        cell.setCellValue("");
                    } else {
                        cell.setCellValue(object.getColumn1());
                    }

                    cell = row.createCell(cellnum++);
                    if (object.getColumn2() == null) {
                        cell.setCellValue("");
                    } else {
                        cell.setCellValue(object.getColumn2());
                    }
                   }

                   FileOutputStream output_file = null;
                try {
                    output_file = new FileOutputStream(new File(a)); 
                } catch (FileNotFoundException ex) {

                }

                try {
                    new_workbook.write(output_file);
                } catch (IOException ex) {

                }

                try {
                    output_file.close(); //close the file
                } catch (IOException ex) {

                }
                FileInputStream fis = null;
                try {
                    fis = new FileInputStream(a);
                } catch (FileNotFoundException ex) {

                }
                InputStream is = fis;
                String mimeType = "";
                try {
                    mimeType = URLConnection.guessContentTypeFromStream(is);
                } catch (IOException ex) {

                }

                return new DefaultStreamedContent(is, mimeType, fileName);
            }    

Disclaimer : Not tested, and you need to adapt the code with your own objects and entities.

来源：https://stackoverflow.com/questions/24889066/issue-with-primefaces-pdataexporter-which-exports-a-datatable-with-selectoneme