Export to Excel using spring and Apache POI.

First include the poi jar file downloaded from apache poi.

Entry in application-servlet.xml:

<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping" />

   

    <bean class="org.springframework.web.servlet.view.XmlViewResolver">

         <property name="location">

             <value>/WEB-INF/spring-excel-views.xml</value>

         </property>

         <property name="order" value="0" />

      </bean>

<bean id="ExcelRevenueSummary"         class="com.application.utility.ExcelRevenueReportView" />

Entry in spring-excel-views.xml :

<beans xmlns="http://www.springframework.org/schema/beans"

      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

      xsi:schemaLocation="http://www.springframework.org/schema/beans

      http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

      <bean id="ExcelRevenueSummary"

            class="com.application.utility.ExcelRevenueReportView">

      </bean>

</beans>

RevenueReportController.java class :

package com.application.utility;

import java.util.HashMap;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.servlet.ModelAndView;

import org.springframework.web.servlet.mvc.AbstractController;

@Controller

@RequestMapping("/exportForClient.htm")

public class RevenueReportController extends AbstractController{

      @Override

      protected ModelAndView handleRequestInternal(HttpServletRequest request,

                  HttpServletResponse response) throws Exception {

           

            //String output = ServletRequestUtils.getStringParameter(request, "output");

           

            //dummy data

            Map<String,String> revenueData = new HashMap<String,String>();

            revenueData.put("Jan/2012", "$10");

            revenueData.put("Feb/2012", "$110,000");

            revenueData.put("Mar/2012", "$130,000");

            revenueData.put("Apr/2012", "$140,000,000");

            revenueData.put("May/2012", "$220,000,000");

           

            System.out.println("RevenueReportController.handleRequestInternal()");

            return new ModelAndView("ExcelRevenueSummary","revenueData",revenueData);

           

      /*    if(output ==null || "".equals(output)){

                  //return normal view

                  return new ModelAndView("RevenueSummary","revenueData",revenueData);

                 

            }else if("EXCEL".equals(output.toUpperCase())){

                  //return excel view

                  return new ModelAndView("ExcelRevenueSummary","revenueData",revenueData);

                 

            }else{

                  //return normal view

                  return new ModelAndView("RevenueSummary","revenueData",revenueData);

                 

            }

      */   

      }

     

}

The commented part can be used to forward your view at different location.

ExcelRevenueReportView.java class :

package com.application.utility;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.poi.hssf.usermodel.HSSFRow;

import org.apache.poi.hssf.usermodel.HSSFSheet;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import org.springframework.web.servlet.view.document.AbstractExcelView;

public class ExcelRevenueReportView extends AbstractExcelView{

     

      @Override

      protected void buildExcelDocument(Map model, HSSFWorkbook workbook,

                  HttpServletRequest request, HttpServletResponse response)

                  throws Exception {

           

           

            Map<String,String> revenueData = (Map<String,String>) model.get("revenueData");

            //create a wordsheet

            HSSFSheet sheet = workbook.createSheet("Data Report");

           

            HSSFRow header = sheet.createRow(0);

            header.createCell(0).setCellValue("Month");

            header.createCell(1).setCellValue("Data");

           

            int rowNum = 1;

            for (Map.Entry<String, String> entry : revenueData.entrySet()) {

                  //create the row data

                  HSSFRow row = sheet.createRow(rowNum++);

                  row.createCell(0).setCellValue(entry.getKey());

                  row.createCell(1).setCellValue(entry.getValue());

                 

        }

      }

}

Call this from your onSubmit method of your controller according to the condition you required.

return "redirect:exportForClient.htm";