How to implement Generate Jasper Report PDF on button click in Liferay Portal 6.1 - pdf

Question

I have a requirement to provide report generation functionality on a button click. I am using Liferay Portal 6.1 with Tomcat 7 as web portal, Liferay Developer Studio (Eclipse Indigo) IDE, iReport (to create report template), and JasperReports library to produce the PDF. The portal is a ticket management system with two entities (Tickets and Documents) which are entered via their respective custom portlets. Both entities, when in edit mode, need the 'View Report' function. I have searched for answers to this problem extensively, picking up a snippet here and there, but nothing I have found is exactly my situation. Upon clicking the 'View Report' button, the user needs to be presented with a formatted PDF where the user can then decide to 'Save', 'Print', or 'Close' from. I also need to pass data to the report so information can be retrieved for the entity that is open (i.e., documentId, ticketId, docType, etc.), but this piece can be added later; once I just get a PDF to open.
Not knowing how to go about implementing this, I decided to use a jQuery Modal to open 'viewReport.jsp' page and process the report there. However, this approach yields a JRException IllegalState: cannot obtain OutputStream because writer is already in use. I have read in my searches that Liferay layout uses OutputStream and that's probably why the writer is already in use. Here's the code I am using:
edit_document.jsp (button and jQuery Modal)
<!-- View Report Button at bottom of form -->
<aui:button type="button" id="viewReportBtn" value="View Report" />
<!-- URL declaration for PDF popup window -->
<portlet:renderURL var="viewReportURL" windowState="<%= LiferayWindowState.EXCLUSIVE.toString() %>" >
<portlet:param name="mvcPath" value="/html/document/viewReport.jsp" />
<portlet:param name="documentId" value="<%= Long.toString(documentID) %>" />
<portlet:param name="ticketId" value="<%= Long.toString(ticketID) %>: />
<portlet:param name="docType" value="<%= docType %>" /> <!-- This is already a String value -->
</portlet:renderURL>
<!-- jQuery to open popup window for PDF -->
<aui:script use="aui-dialog, aui-overlay-manager, dd-constrain" >
var reportDialogOptions = {
title : 'Dialog',
bodyContent : '',
centered : true,
group : default,
height : 800,
width : 1000,
modal : true,
};
$('#viewReportBtn').on('click', finction(event) {
var editFeelingDialog = new A.Dialog(
A.merge(reportDialogOptions, {
title : 'Document View Report'
})
).plugin(A.Plugin.IO,{uri : '<%= viewReportURL %>'}).render();
});
</aui:script>
viewReport.jsp (page to process jrxml template and open PDF)
<!-- viewReport.jsp page to render PDF -->
<%# page contentType = "application/pdf" %>
<%# page trimDirectiveWhitespaces = "true" %>
<%# page import = "net.sf.jasperreports.engine.*" %>
<%# page import = "java.io.File" %>
<%# page import = "java.io.FileInputStream" %>
<%# page import = "java.io.FileNotFoundException" %>
<%# page import = "java.io.InputStream" %>
<%# page import = "java.sql.Connection" %>
<%# page import = "java.sql.SQLException" %>
<%
Connection conn = null;
try
{
String url = "jdbc:oracle:thin:#myDBSRV:1521:myDatabase";
String userName = "myUsername";
String password = "myPassword";
// Connecting to the Oracle database
Class.forName("oracle.jdbc.driver.OracleDriver");
conn = DriverManager.getConnection(url, username, password);
// Loading the Jasper Report file from local file system\
String jrxmlFile = session.getServletContext().getRealPath(request.getContextPath())+"\\report5.jrxml";
InputStream input = new FileInputStream(new File(jrxmlFile));
// Generate the report
JasperReport jasperReport = JasperCompileManager.compileReport(input);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperPrint, null, conn);
// Export the report as a PDF
JasperExportManager.exportReportToPdfStream(jasperPrint, response.getOutputStream());
}
catch (FileNotFoundExcecption ex)
{
System.out.println(ex.getMessage());
ex.printStakeTrace();
}
catch (JRException ex)
{
System.out.println(ex.getMessage());
ex.printStakeTrace();
}
catch (ClassNotFoundException ex)
{
System.out.println(ex.getMessage());
ex.printStakeTrace();
}
catch (SQLException ex)
{
System.out.println(ex.getMessage());
ex.printStakeTrace();
}
finally
{
if (conn != null)
{
conn.close();
}
}
%>
I also tried to add java methods to my DocumentPortlet.java class and call the method(s) when the button is clicked, but I am not that familiar enough with ajax to get it right:
DocumentPortlet.java
public class DocumentPortlet extends MVCPortlet{
Connection conn = null;
// More methods for saving, editing, and deleting documents are here...
public void generateReport()
{
initConnection();
showReport();
}
public void initConnection()
{
String host = "jdbc:oracle:thin:#ncimsdbsrv:1521:ncimsdev";
String userName = "lportal";
String password = "NSS4207itnp";
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
}
catch(ClassNotFoundException ex)
{
ex.printStackTrace();
}
try
{
conn = DriverManager.getConnection(host, userName, password);
}
catch (SQLException ex)
{
ex.printStackTrace();
}
}
public void showReport()
{
//Path to your .jrxml file
String reportName = "[path to file]";
//Get a stream to read the file
InputStream is = this.getClass().getClassLoader().getResourceAsStream(reportName);
try
{
//Fill the report with parameter, connection, and stream reader
JasperPrint jp = JasperFillManager.fillReport(is, null, session);
//Viewer for Jasper report
JRViewer jv = new JRViewer(jp);
//Insert viewer to a JFrame to make it showable
JFrame jf = new JFrame();
jf.getContentPane().add(jv);
jf.validate();
jf.setVisible(true);
jf.setSize(new Dimension(800, 600));
jf.setLocation(300, 100);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
catch (JRException ex)
{
ex.printStakeTrace();
}
finally
{
closeSession(session);
}
}
}
How can I provide this functionality in a way that my users can click the button and a PDF be generated on their screen? I need a clear and concise solution to this problem. Thank you!
Lee

Answer 1

In case anyone is interested, I found an answer on a Liferay forum. My implementation was not correct. So now I have this in my
viewDocument.jsp:
<!-- View Report button at bottom of form -->
<aui:button id="viewReportBtn" value="View Report" />
<!-- URL declaration for PDF generation -->
<portlet:resourceURL id="generatePDF" var="generateReportURL" >
<portlet:param name="jspPage" value="/html/document/viewReport.jsp" />
<portlet:param name="docType" value="<%= docType %>" />
</portlet:resourceURL>
<!-- AJAX call to resource request handler in DocumentPortlet.java file -->
<aui:script use="aui-dialog, aui-overlay-manager, dd-constrain" >
$(document).ready(function()
{
$('#viewReportBtn').click(function(event)
{
$.ajax('<%= generateReportURL %>');
}
});
I also created the ResourceRequestHandler in my Portlet java file like so:
DocumentPortlet.java:
public class DocumentPortlet extends MVCPortlet{
Connection conn = null;
// More methods to add, update, and delete here
#Override
public void serveResource(ResourceRequest request, ResourceResponse response)
throws IOException, PortletException
{
String url = "jdbc:oracle:thin:#myDatabaseSrv:1521:myDatabaseSid";
String user = "myUserName";
String pass = "myPassword";
String docType = ParamUtil.getString(request, "docType");
try
{
// Connect to database
Class.forName("oracle.jdbc.driver.OracleDriver");
conn = DriverManager.getConnection(url, user, pass);
// Load JRXml file from local file system
String jrxmlFile = "C:\\Reports\\report5.jrxml";
InputStream input = new FileInputStream(new File(jrxmlFile));
// Generate report
JasperReport jasperReport = JasperCompileManager.compileReport(input);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperPrint, null, conn);
/***** Display PDF in Adobe Reader *****/
// Create new OutputStream where data is written to byte array[]
ByteArrayOutputStream output = new ByteArrayOutputStream();
// Export the report to PDF format
JasperExportManager.exportReportToPdfStream(jasperPrint, output);
// Create a String for thr report title
final String fileName = docType + ".pdf";
//Create a new stream and call the report
OutputStream pdfFile = new FileOutputStream(new File(fileName));
//Write the PDF
pdfFile.write(output.toByteArray());
//Clean the PDF
pdfFile.flush();
//Close it
pdfFile.close();
//Run the brand new PDF report
final String PDF_RUN = "rundll32 url.dll, FileProtocolHandaler " + fileName;
//Execute the command
Runtime.getRuntime().exec(PDF_RUN);
}
catch(FileNotFoundException ex)
{
System.out.println("File not found on file system, check file path!!" + ex.getMessage());
ex.printStackTrace();
}
catch(JRException ex)
{
System.out.println("Error in Jasper Report!!" + ex.getMessage());
ex.printStackTrace();
}
catch(ClassNotFoundException ex)
{
System.out.println("Oracle Class for driver not found!!" + ex.getMessage());
ex.printStackTrace();
}
catch(SQLException ex)
{
System.out.println("Error getting connection to database!!" + ex.getMessage());
ex.printStackTrace();
}
}
}
This eliminated the IllegalStateException I was getting and will open the pdf in Adobe Reader just fine, however, it opens it up on the server. Therefore, a problem still remains. Anybody know how I can get this pdf to open on the client machine?