java - 如何将jsp中描述的字段或值传递给jasper报表，以便它可以以PDF格式显示数据

Question

我使用 Eclipse，下面是代码的一部分

<!--menu.jsp-->
<h1>Pass parameter to jasper report(CI_ID)</h1>
<form action = "call.jsp" target="_blank">
<input type= "text" name = "CI_ID" value = ""/><br/> 
<input type="submit" value="Print"/>
</form>

<!--call.jsp-->
<%Connection conn = null;
int id=Integer.parseInt(request.getParameter("CI_ID"));
try{
Class.forName("org.gjt.mm.mysql.Driver").newInstance();
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root","1234");
File reportFile = new File(application.getRealPath("//Report.jasper"));
Map parameters = new HashMap();
parameters.put("CI_ID",id);

byte[] bytes = JasperRunManager.runReportToPdf(reportFile.getPath(),parameters,conn);
response.setContentType("application/pdf");
response.setContentLength(bytes.length);
ServletOutputStream outStream = response.getOutputStream();
outStream.write(bytes, 0 , bytes.length);
response.getOutputStream().flush();
response.getOutputStream().close();
} catch (Exception e){
    e.printStackTrace();
}%>

我在 Jasper 报告上预览没有任何问题，但是当我使用 JSP 将参数传递给 Eclipse 上的 Jasper 报告时，我收到此错误“文件不以 '%PDF-' 开头。” adobe reader 的弹出窗口。

我尝试了以下解决方案，但仍然不起作用

1)更改为

response.setContentType("application/pdf");

response.setContentType("application/x-pdf");

2)更新adobe reader

3)导入jasper所有相关的.jar

Answer 1

首先，您拥有 session 属性和 request.getParameters，以便您可以将这些参数发送到 jasper 报告。我将展示一个示例以便更好地理解。我有一个jsp页面，例如搜索数据.jsp

 <form action="searchResult.jsp" method="POST">
                    <table border="0" width="" cellspacing="15" cellpadding="1">
                        <thead>
                            <tr>
                                <th>Search Using:</th>
                                <th><select name="search">
                                        <option value=""> Select</option>
                                        <option value="Company Name">Company Name</option>
                                        <option value="Contact Person">Contact Person</option>
                                        <option value="Phone">Phone Number</option>
                                    </select></th>


                                <th><input type="text" name="search_tf" /></th>
                                <th><input type="submit" value=" " class="search_btn"/></th>
                            </tr>
                        </thead>
                        <tr>
                            <td></td><td></td><td></td><td></td>
                            <td><small>(Blank Search will result in Full Search Result)</small></td>
                        </tr>
                    </table>
                </form>

单击提交按钮后，因为我的操作为“searchResult.jsp”，它将转到搜索结果.jsp

在searchResult.jsp页面中，我使用了request.getParameter，以便在前一个jsp页面中输入的数据现在将进入当前jsp页面，然后我使用 session 属性，以便它可以在进一步的jsp页面，直到 session 结束。如下所示

Search Result for <u><%= request.getParameter("search_tf")%></u> in <u><%= request.getParameter("search")%></u> is :

 Object o2 = session.getAttribute("email");
                                    String email = o2.toString();
                                    String category = request.getParameter("category");
                                    String search = request.getParameter("search");
                                    session.setAttribute("search",search);
                                    String search_tf = request.getParameter("search_tf");
                                    session.setAttribute("search_tf",search_tf);

然后是我的sql查询，我给出了一个sql查询的例子

if(search.equals("")&& search_tf.equals("")){
                                        sqlPgintn="SELECT SQL_CALC_FOUND_ROWS Id,Company_name,Contact_Person,Address,Phone,Company_Email,Review,Status,Lead_Date,Lead_Details,Lead_Value,followup_Date,Category from marketing_database.lead limit "+iPagNo+","+iSwRws+"";
}
 else if(search.equals("Company Name"))
                                    {   
                                        sqlPgintn="SELECT SQL_CALC_FOUND_ROWS Id,Company_name,Contact_Person,Address,Phone,Company_Email,Review,Status,Lead_Date,Lead_Details,Lead_Value,followup_Date,Category from marketing_database.lead where Company_Name ='"+search_tf+"' limit "+iPagNo+","+iSwRws+"";

现在我使用 javascript 做到了这一点

<script type="text/javascript">
 function generateReport() {
  var e = document.getElementById("idOfYourSelectYouNeedToAddedIt");
  var strPage = e.options[e.selectedIndex].value;
  window.open(strPage);
 return false; //This make you stay on this page;
  //return true; //Set the action tag in the form to the page you like to go to!
 }
</script>
<center>       <form name="myForm" onsubmit="return generateReport()">
               <select id = "idOfYourSelectYouNeedToAddedIt">
<option value=''> Generate Report </option>
<option value='samplePDF.jsp'> PDF</option>
<option value='sampleDOC.jsp'> DOC </option>
<option value='sampleXLS.jsp'> XLS</option>
<option value='sampleXLSX.jsp'> XLSX </option>
</select>
<br/>

<input type="submit" value="Submit">
</form></center>

当我点击假设“samplePDF.jsp”时，它会转到该页面，我就这样做了示例PDF.jsp

<%
Connection conn = null;
Object o2 = session.getAttribute("email");
String email = o2.toString();
String category=(String)session.getAttribute("category");
String status=(String)session.getAttribute("status");
String startDate=(String)session.getAttribute("startDate");
String endDate=(String)session.getAttribute("endDate");

try 
{
    Class.forName("com.mysql.jdbc.Driver");
    conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/marketing_database","root","root");
    String sql = "select * from lead where Email = '" + email + "' AND Status LIKE '%" + status + "%' AND Category LIKE '%" + category + "%' AND STR_TO_DATE(`Lead_Date`, '%d-%m-%Y') BETWEEN '"+startDate+"' AND '"+endDate+"'";
    ServletContext context = request.getServletContext(); 
    String fullPath = context.getRealPath("/WEB-INF/reports/report10.jrxml");
    InputStream input = new FileInputStream(new File(fullPath));
    JasperDesign jasperDesign = JRXmlLoader.load(input);

    System.out.println("Compiling Report Designs");
    JasperReport jasperReport = JasperCompileManager.compileReport(jasperDesign);

    System.out.println("Creating JasperPrint Object");
    HashMap<String,Object> map = new HashMap<String,Object>();
    map.put("sql",sql);
            byte[] bytes = JasperRunManager.runReportToPdf(jasperReport, map, conn);

            response.setContentType("application/pdf");
            response.setContentLength(bytes.length);
            ServletOutputStream outStream = response.getOutputStream();
            outStream.write(bytes, 0, bytes.length);
            outStream.flush();
            outStream.close();
            conn.close();
}
catch(Exception e) 
{e.printStackTrace();} 

        %>