Java后臺代碼的實現

申明：直接拷貝代碼會有錯誤，這里只是為了說明流程。

前面一節中已經創建了DataBean，這一節主要來完成報表的填充。

1、?需要把所有報表中展現的數據封裝成一個DataBean對象的List

package?direction.shoufei.report.groupyearfee.model;

import?java.util.List;
import?direction.shoufei.report.groupyearfee.data.CenterYearFee;

public?class?CenterYearFeeModel?{
????public?List<CenterYearFee>?getCenterYearFeeList(String?year)?{
????????//這里通過連接數據庫或者其它方式將報表中展現的數據封裝為一個List
????????return?List對象;
????}
}

?

2、?? ?生成數據源，必須實現JRDataSource接口package?direction.shoufei.report.groupyearfee.datasource;

import?java.util.ArrayList;
import?java.util.List;

import?net.sf.jasperreports.engine.JRDataSource;
import?net.sf.jasperreports.engine.JRException;
import?net.sf.jasperreports.engine.JRField;
import?direction.shoufei.report.groupyearfee.data.CenterYearFee;
import?direction.shoufei.report.groupyearfee.model.CenterYearFeeModel;

public?class?CenterYearFeeDataSource?implements?JRDataSource?{

????private?List<CenterYearFee>?data?=?new?ArrayList<CenterYearFee>();

????public?CenterYearFeeDataSource(String?year)?{
????????data?=?new?CenterYearFeeModel().getCenterYearFeeList(year);
????}

????private?int?index?=?-1;

????@Override
????public?Object?getFieldValue(JRField?field)?throws?JRException?{
????????Object?value?=?null;

????????String?fieldName?=?field.getName();

????????if?("centerId".equals(fieldName))?{
????????????value?=?data.get(index).getCenterId();
????????}?else?if?("centerName".equals(fieldName))?{
????????????value?=?data.get(index).getCenterName();
????????}?else?if?("summary".equals(fieldName))?{
????????????value?=?data.get(index).getSummary();
????????}?else?if?("preYearRate".equals(fieldName))?{
????????????value?=?data.get(index).getPreYearRate();
????????}?else?if?("month1Fee".equals(fieldName))?{
????????????value?=?data.get(index).getMonth1Fee();
????????}?else?if?("month2Fee".equals(fieldName))?{
????????????value?=?data.get(index).getMonth2Fee();
????????}?else?if?("month3Fee".equals(fieldName))?{
????????????value?=?data.get(index).getMonth3Fee();
????????}
????????...
????????return?value;
????}

????@Override
????public?boolean?next()?throws?JRException?{
????????index++;
????????return?(index?<?data.size());
????}
}

?

3、?填充報表

a-接口

package?direction.shoufei.report.groupyearfee.service;

public?interface?CenterYearFeeService?{
????/**
?????*?填充報表
?????*?@param?year?某年的報表
?????*/
????void?fillCenterYearFeeToReport(String?year);
}

b-填充報表的實現

package?direction.shoufei.report.groupyearfee.service.support;

import?java.io.File;
import?java.util.Date;
import?java.util.HashMap;
import?java.util.Map;

import?net.sf.jasperreports.engine.JRException;
import?net.sf.jasperreports.engine.JRRuntimeException;
import?net.sf.jasperreports.engine.JasperFillManager;
import?net.sf.jasperreports.engine.JasperPrint;
import?net.sf.jasperreports.j2ee.servlets.BaseHttpServlet;
import?direction.framework.utils.WebRootPath;
import?direction.shoufei.report.groupyearfee.datasource.CenterYearFeeDataSource;
import?direction.shoufei.report.groupyearfee.service.CenterYearFeeService;
import?direction.shoufei.report.util.DateFormatUtil;
import?flex.messaging.FlexContext;

public?class?CenterYearFeeServiceImpl?implements?CenterYearFeeService{

????@Override
????public?void?fillCenterYearFeeToReport(String?year)?{
????????//用iReport設計好的報表編譯之后的路徑
????????String?reportFileName?=?new?WebRootPath().getWebRootPath()
????????+?"/reports/shoufei/groupyearfee/GroupYearFee.jasper";
????????File?reportFile?=?new?File(reportFileName);
????????if?(!reportFile.exists())
????????????throw?new?JRRuntimeException(
????????????????????"File?GroupYearFee.jasper?not?found.?The?report?design?must?be?compiled?first.");
????????//填充報表時向報表傳遞的參數
????????Map?parameters?=?new?HashMap();
????????parameters.put("QueryYear",?year);
????????
????????String?endTimeStr?=?year+"-12-26";
????????Date?endTime?=?DateFormatUtil.getDateByStr(endTimeStr);
????????if(new?Date().getTime()>endTime.getTime()){
????????????endTimeStr?=?DateFormatUtil.getStrByDate(endTime);
????????}else{
????????????endTimeStr?=?DateFormatUtil.getStrByDate(new?Date());
????????}
????????
????????parameters.put("QueryEndTime",?endTimeStr);
????????parameters.put("PreYear",?DateFormatUtil.getPreYear(year));
????????
????????try?{
????????????//這里將生成的數據源和參數填充到報表里
????????????JasperPrint?jasperPrint?=?JasperFillManager.fillReport(
????????????????????reportFileName,?parameters,
????????????????????new?CenterYearFeeDataSource(year));
????????????FlexContext.getHttpRequest().getSession().setAttribute(
????????????????????BaseHttpServlet.DEFAULT_JASPER_PRINT_SESSION_ATTRIBUTE,
????????????????????jasperPrint);
????????}?catch?(JRException?e)?{
????????????e.printStackTrace();
????????}
????}
}

?

這樣就完成了報表的填充，報表的展現將在下一節說明。

?

?

轉載于:https://www.cnblogs.com/wangtory/archive/2011/03/21/iReport3.html

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