连接主报表和子报表 – 将对象列表传递到子报表
我正在使用iReport 4.5.1 ,我遇到了连接主报表和子报表的问题。
我有两个对象:
- 帐户 (accountID,date,listOfParagraphs) – 所有字段都在主报告中定义;
- 段落 (account,paragraphNo,someObject) – 在子报表( stavke.jrxml )中定义的所有字段。
listOfParagraphs定义为java.util.List
(对象列表),我想将它传递给子报表。
我在主报告中定义了这个子报告的属性:
- 子报表表达式 : stavke.jasper
- 表达式类 : java.lang.String
- 连接类型 : 使用数据源表达式
- 数据源表达式 :
new net.sf.jasperreports.engine.data.JRBeanCollectionDataSource($F{listOfParagraphs})
我收到此错误:
net.sf.jasperreports.engine.JRException: Error loading object from file : stavke.jasper at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:101) at net.sf.jasperreports.engine.util.JRLoader.loadObjectFromLocation(JRLoader.java:253) at net.sf.jasperreports.engine.fill.JRFillSubreport.evaluateReport(JRFillSubreport.java:301) .....
我已经为此努力了,但我无法解决它。
有人能帮助我吗?
@Vyccus(已编辑)
我改变了路径:
和
现在我明白了:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at java.lang.Class.isAssignableFrom(Native Method) at net.sf.jasperreports.engine.fill.JRFillTextField.getFormat(JRFillTextField.java:706) at net.sf.jasperreports.engine.fill.JRFillTextField.evaluateText(JRFillTextField.java:394) at net.sf.jasperreports.engine.fill.JRFillTextField.evaluate(JRFillTextField.java:368) at net.sf.jasperreports.engine.fill.JRFillElementContainer.evaluate(JRFillElementContainer.java:258) at net.sf.jasperreports.engine.fill.JRFillBand.evaluate(JRFillBand.java:499) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillColumnBand(JRVerticalFiller.java:2036) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillDetail(JRVerticalFiller.java:760) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReportStart(JRVerticalFiller.java:270) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:128) at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:946) at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:864) at net.sf.jasperreports.engine.fill.JRFillSubreport.fillSubreport(JRFillSubreport.java:613) at net.sf.jasperreports.engine.fill.JRSubreportRunnable.run(JRSubreportRunnable.java:59) at net.sf.jasperreports.engine.fill.JRThreadSubreportRunner.run(JRThreadSubreportRunner.java:205) at java.lang.Thread.run(Thread.java:662)
Java代码:
Map parameters = new HashMap(); //if you want this to be compiled in runtime JasperReport jasperReport = JasperCompileManager.compileReport(your JRXMLReport path file here); JasperReport subReport = JasperCompileManager.compileReport(your JRXMLSubReport path file here); //you can notice that there're a lot of overloaded mathods to compile it, you can choose //what is better in your case //if you want to use the complied file *.jasper JasperReport jasperReport = (JasperReport)JRLoader.loadObject(new File("filenameReport.jasper")); JasperReport subReport = (JasperReport)JRLoader.loadObject(new File("filenameSubReport.jasper")); //Then you add your subReport in your parameter Map parameters.put("SUBREPORT_JASPER_FILE", subReport); JasperFillManager.fillReport(jasperReport, parameters, new JRBeanCollectionDataSource(yourList));
JRXML:
// you can also create this using the option in your iReport
我认为这样你就可以完成你想要做的事情