Flex 调用 Applet、Applet 利用jasperreport进行打印

最新推荐文章于 2021-03-02 12:23:11 发布

最新推荐文章于 2021-03-02 12:23:11 发布 · 180 阅读

文章标签：

#Flex #CSS #JavaScript #Servlet #HTML #ViewUI

web打印专栏收录该内容

2 篇文章

订阅专栏

本文介绍了一种使用Flex应用程序调用JasperReport进行指定打印机打印的方法。通过JavaScript和Applet作为中间桥梁，最终由Servlet负责调用JasperReport进行报表打印。文章提供了关键代码示例，并附带了实现过程中的注意事项。

一、需求

Flex 作为用户界面，调用打印机（需要指定打印机名称）直接进行打印。

二、分析

Flex就目前而言，调用打印机时，每次都会弹出选择打印机的对话框。需点击确认按钮然后才进行打印。我需要打印时，直接打印出来，打印机由程序指定。同时为了打印内容易设计，我打印时用到了JasperReport。由于Applet可以指定打印机名称，我实现的方式如下：

Flex 调用　JavaScript

JavaScript 调用Applet

Applet调用Servlet

Servlet利用Jasperreport进行打印

三、实现（关键代码）

1.创建一个Servlet，负责调用jasperreport

public class JasperPrintServlet extends HttpServlet

{

/**

public void service(

HttpServletRequest request,

HttpServletResponse response

) throws IOException, ServletException

{

ServletContext context = this.getServletConfig().getServletContext();

String param=request.getParameter("param");

String[] ps=param.split(",");

try

{

JasperCompileManager.compileReportToFile(context.getRealPath("/reports/WebappReport.jrxml"));

File reportFile = new File(context.getRealPath("/reports/WebappReport.jasper"));

if (!reportFile.exists())

throw new JRRuntimeException("File WebappReport.jasper not found. The report design must be compiled first.");

Map parameters = new HashMap();

parameters.put("P1", ps[0]);

parameters.put("P2", ps[1]);

parameters.put("BaseDir", reportFile.getParentFile());

JasperPrint jasperPrint = null;

JasperReport jasperReport = (JasperReport)JRLoader.loadObject(reportFile.getPath());

jasperPrint =

JasperFillManager.fillReport(

jasperReport,

parameters,

//new WebappDataSource()

new JREmptyDataSource()

);

request.getSession().setAttribute(BaseHttpServlet.DEFAULT_JASPER_PRINT_SESSION_ATTRIBUTE, jasperPrint);

if (jasperPrint != null)

{

response.setContentType("application/octet-stream");

ServletOutputStream ouputStream = response.getOutputStream();

ObjectOutputStream oos = new ObjectOutputStream(ouputStream);

oos.writeObject(jasperPrint);

oos.flush();

oos.close();

ouputStream.flush();

ouputStream.close();

}

else

{

response.setContentType("text/html");

PrintWriter out = response.getWriter();

out.println("<html>");

out.println("<head>");

out.println("<title>JasperReports - Web Application Sample</title>");

out.println("<link rel=\"stylesheet\" type=\"text/css\" href=\"../stylesheet.css\" title=\"Style\">");

out.println("</head>");

out.println("<body bgcolor=\"white\">");

out.println("<span class=\"bold\">Empty response.</span>");

out.println("</body>");

out.println("</html>");

}

System.out.println("print ---------------------");

}

catch (Exception e)

{

e.printStackTrace();

response.setContentType("text/html");

PrintWriter out = response.getWriter();

out.println("<html>");

out.println("<head>");

out.println("<title>JasperReports - Web Application Sample</title>");

out.println("<link rel=\"stylesheet\" type=\"text/css\" href=\"../stylesheet.css\" title=\"Style\">");

out.println("</head>");

out.println("<body bgcolor=\"white\">");

out.println("<span class=\"bnew\">JasperReports encountered this error :</span>");

out.println("<pre>");

e.printStackTrace(out);

out.println("</pre>");

out.println("</body>");

out.println("</html>");

return;

}

2.创建 Applet

public class HelloSwingApplet extends JApplet

{

private URL url = null;

private JasperPrint jasperPrint = null;

public HelloSwingApplet()

{

}

public void init2(String param)

{

String strUrl = getParameter("REPORT_URL");

if (strUrl != null)

{

try

{

url = new URL(getCodeBase(), strUrl+"?param="+param);

}

catch (Exception e)

{

StringWriter swriter = new StringWriter();

PrintWriter pwriter = new PrintWriter(swriter);

e.printStackTrace(pwriter);

JOptionPane.showMessageDialog(this, swriter.toString());

}

if (url != null)

{

try

{

jasperPrint = (JasperPrint)JRLoader.loadObject(url);

if (jasperPrint == null)

JOptionPane.showMessageDialog(this, "Empty report.");

}

catch (Exception e)

{

StringWriter swriter = new StringWriter();

PrintWriter pwriter = new PrintWriter(swriter);

e.printStackTrace(pwriter);

JOptionPane.showMessageDialog(this, swriter.toString());

}

3.Flex 的swf文件对应的html部分代码

function print(param){

document.applets[0].printReport(param);

}

function focusswf(){

report.focus();

}

</script>

</APPLET>

注意事项

注意红色代码：codebase="http://localhost:8500/webprint"，这个值随具体环境做相应变化，Archive这个属性值也不可丢弃

4.Flex 调用 js 代码

if(ExternalInterface.available){

ExternalInterface.call("print",paravalues);

}

5.附上工程代码

速度极其慢，无法上传(好像現在無法上傳哦）

我现在将后缀名rar改成jpg上传，下载完了的话将jpg改成rar，再解压即可。

说明：client.jpg 是Flex 客户端；webprint.jpg 是服务器端，服务器端涉及到的lib是jasperreport3.0的lib加上blaszeDS的lib。在此不上传