JasperReport 使用JavaBean最为数据源出错，请高手解答！

Question

我是按照JasperReport for Java Developers.pdf来做的
public class FirstReportAction extends DispatchAction {
 
private JRDateSource createReportDataSource() {
JRBeanCollectionDataSource dataSource;
Collection reportRows=initlializeBeanCollection();
dataSource=new JRBeanCollectionDataSource(reportRows);
return dataSource;
}


@SuppressWarnings("unchecked")
private Collection initlializeBeanCollection(){
 ArrayList reportRows=new ArrayList();
 reportRows.add(new OuserBO("1","2","3"));
 return reportRows;
}

@SuppressWarnings("unchecked")
public ActionForward first(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response) throws IOException {

    ServletOutputStream servletOutputStream = response.getOutputStream();
        InputStream reportStream = this.getServlet().getServletConfig().getServletContext()
          .getResourceAsStream("/reports/ka.jasper");
        
     try
      {
      JRDateSource dataSource=createReportDataSource();
      JasperRunManager.runReportToPdfStream(reportStream, servletOutputStream,new HashMap  
                  (),dataSource);
      servletOutputStream.flush();
 servletOutputStream.close();  
               }错误：
private JRDateSource createReportDataSource()行报错如下：
JRDateSource cannot be resolved to a typeJRDateSource dataSource=createReportDataSource()行报错如下
 JRDateSource cannot be resolved to a type
 The method createReportDataSource() is undefined for the type FirstReportAction  
 
请问是什么原因？
   
     

Answer 1

createReportDataSource() is undefined 方法没有定义啊,复制别人的代码而不理解是永远学不好JAVA的.

Answer 2

有没有导入包啊?
import net.sf.jasperreports.engine.JRDataSource; 
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;