提供的java.sql.Connection对象为空
我正在尝试将jrxml文件导出为pdf,但出现以下错误:提供的java.sql.Connection对象为空,java,jasper-reports,Java,Jasper Reports,我正在尝试将jrxml文件导出为pdf,但出现以下错误: WARN query.JRJdbcQueryExecuter - The supplied java.sql.Connection object is null. 我只得到一个空白的pdf文件 这是我导出为PDF的方法: public void printReport(ActionEvent event) throws JRException, IOException { String reportPath = FacesC
WARN query.JRJdbcQueryExecuter - The supplied java.sql.Connection object is null.
我只得到一个空白的pdf文件
这是我导出为PDF的方法:
public void printReport(ActionEvent event) throws JRException, IOException {
String reportPath = FacesContext.getCurrentInstance().getExternalContext().getRealPath("/test.jrxml");
JasperReport report = JasperCompileManager.compileReport(reportPath);
JasperPrint jasperPrint = JasperFillManager.fillReport(report, new HashMap<String, String>());
HttpServletResponse httpServletResponse = (HttpServletResponse) FacesContext.getCurrentInstance().getExternalContext().getResponse();
httpServletResponse.addHeader("Content-disposition", "attachment; filename=report.pdf");
ServletOutputStream servletOutputStream = httpServletResponse.getOutputStream();
JasperExportManager.exportReportToPdfStream(jasperPrint, servletOutputStream);
FacesContext.getCurrentInstance().responseComplete();
}
public void printReport(ActionEvent事件)引发JREException、IOException{
字符串reportPath=FacesContext.getCurrentInstance().getExternalContext().getRealPath(“/test.jrxml”);
JasperReport report=jaspecompilemanager.compileReport(reportPath);
JasperPrint-JasperPrint=JasperFillManager.fillReport(report,newhashmap());
HttpServletResponse HttpServletResponse=(HttpServletResponse)FacesContext.getCurrentInstance().getExternalContext().getResponse();
addHeader(“内容处置”,“附件;文件名=report.pdf”);
ServletOutputStream ServletOutputStream=httpServletResponse.getOutputStream();
导出报告topdfstream(jasperPrint,servletOutputStream);
FacesContext.getCurrentInstance().responseComplete();
}
我是jasperreports的新手,所以我有点迷路了。。我必须指定de数据库的连接字符串还是什么?我应该在哪里添加它
顺便说一句,我正在使用JSF2、intellij和maven
谢谢。我解决了我的问题。。我必须为我的报告指定一个DB连接
Connection conn;
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
conn = DriverManager.getConnection("jdbc:sqlserver://localhost:55334;databaseName=Frutemu;integratedSecurity=true","","");
} catch (SQLException ex) {
} catch (ClassNotFoundException ex) {
}
然后在此行中添加连接:
JasperPrint jasperPrint = JasperFillManager.fillReport(report, new HashMap<String, String>(), conn);
JasperPrint-JasperPrint=JasperFillManager.fillReport(report,new HashMap(),conn);
如果希望使用Java Bean作为源代码而不是DB连接,可以这样做以避免出现异常:
final JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, JRBeanCollectionDataSource(fields));