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JasperReports: How to call the report in jsp page
(6 answers)
Closed 6 years ago.
I'm new to JasperReports and dont know how to call jasper file from servlet. My report contains the pie chart.
You can prepare the Jasper file and stream it to the client.
bytes[] byteStream = JasperRunManager.runReportToPdf("myJasperReport.jasper",paramMap,databaseConn);
OutputStream outStream = servletResponse.getOutputStream();
response.setHeader("Content-Disposition","inline, filename=myReport.pdf");
response.setContentType("application/pdf");
response.setContentLength(byteStream.length);
outStream.write(bytes,0,bytes.length);
Here is a dummy report created within a Servlet file.
It is the same as it would be in normal Java class.
Just make sure you have the imports for your jasper report classes at the top of the file.
The bellow example builds a report from an XML datasource.
public class JasperServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
try {
String reportFile = "myJasperReport.jrxml";
File outputFile = new File("Report.pdf");
HashMap hm = new HashMap();
DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory
.newDocumentBuilder();
Document document = documentBuilder.parse(new File("myXml.xml"));
// Compile the report
JasperReport report = JasperCompileManager
.compileReport(reportFile);
JRXmlDataSource xml = new JRXmlDataSource(document, "/xml/root");
// Fill the report
JasperPrint print = JasperFillManager.fillReport(report, hm, xml);
// Create an Exporter
JRExporter exporter = new JRPdfExporter();
exporter.setParameter(JRExporterParameter.OUTPUT_FILE, outputFile);
exporter.setParameter(JRExporterParameter.JASPER_PRINT, print);
// Export the file
exporter.exportReport();
} catch (Exception e) {
e.printStackTrace();
}
}
}
A complete way to do this from the servlet would be:
public void myServletMethod(HttpServletRequest request, HttpServletResponse response) throws IOException{
JasperReport jasperReport = null;
JasperDesign jasperDesign = null;
Map parameters = new HashMap();
String path = getServletContext().getRealPath("/WEB-INF/");
jasperDesign = JRXmlLoader.load(path+"/relative/path/to/MyReport.jrxml");
jasperReport = JasperCompileManager.compileReport(jasperDesign);
byte[] byteStream = JasperRunManager.runReportToPdf(jasperReport, parameters, **new DataSourceOfYourPreference**);
OutputStream outStream = response.getOutputStream();
response.setHeader("Content-Disposition","inline, filename=myReport.pdf");
response.setContentType("application/pdf");
response.setContentLength(byteStream.length);
outStream.write(byteStream,0,byteStream.length);
}
Related
I wish to show this file on page but this code make a direct download
<a th:href="#{/pdf/Manjaro-User-Guide.pdf}">Show Pdf file</a>
I'm using Spring-Thymeleaf
Thanks!
I found the solution by commenting the line below
//response.setHeader("Content-Disposition", "attachment; filename=\"demo.pdf\"");
Here is the code example:
#GetMapping(value = "/pdf")
public void showPDF(HttpServletResponse response) throws IOException {
response.setContentType("application/pdf");
//response.setHeader("Content-Disposition", "attachment; filename=\"demo.pdf\"");
InputStream inputStream = new FileInputStream(new File(rootLocation + "/Manjaro-User-Guide.pdf"));
int nRead;
while ((nRead = inputStream.read()) != -1) {
response.getWriter().write(nRead);
}
}
Source
Thanks!
I am using ModelAndView pattern to return excel representation of data that is generated in the Controller using Apache POI library.
However the excel gets corrupted(special characters are replaced with ?) when it gets downloaded. If I write the excel to file before pushing it out on the HTTP response, then a valid excel is output.
Here is the controller code that pushes control to ModelAndView
Map<String, Object> model = new HashMap<String, Object>();
model.put(ExcelBusinessReportView.KEY_REPORT_DISPLAY_DATA, reportData);
model.put(ExcelBusinessReportView.KEY_REPORT_DATE, reportRequestDTO.getReportDateUTCAtMidnight());
return new ModelAndView("excelBusinessReportView", model);
And here is the view class
#Service(value = "excelBusinessReportView")
public class ExcelBusinessReportView extends AbstractXlsView {
public static final String KEY_REPORT_DISPLAY_DATA = "reportData";
public static final String KEY_REPORT_DATE = "reportDate";
private static final String MIME_TYPE_EXCEL = "application/ms-excel";
private static final String HEADER_VALUE_CONTENT_DISPOSITION = "attachment; filename=qup_report.xls";
private static final String[] SUMMARY_HEADERS = ........
private static final String[] DETAIL_HEADERS = ........
#Override
protected void buildExcelDocument(Map<String, Object> model, Workbook workbook, HttpServletRequest request,
HttpServletResponse response) throws Exception {
BusinessSlotReportResource reportDisplayData = (BusinessSlotReportResource) model.get(KEY_REPORT_DISPLAY_DATA);
DateTime reportDate = (DateTime) model.get(KEY_REPORT_DATE);
// Build excel document
Sheet sheet = workbook.createSheet(reportDate.toString(CommonConstants.IST_DATE_FORMATTER_PATTERN));
sheet.setDefaultColumnWidth((short) 12);
Integer currentRow = 0;
// Build summary data
currentRow = this.buildSummaryData(workbook, sheet, reportDisplayData, currentRow);
// Create margin rows
sheet.createRow(currentRow++);
sheet.createRow(currentRow++);
// Build detail data
this.buildDetailsData(workbook, sheet, reportDisplayData, currentRow);
response.setContentType(MIME_TYPE_EXCEL);
response.setHeader(HttpHeaders.CONTENT_DISPOSITION, HEADER_VALUE_CONTENT_DISPOSITION);
}
Content of excel when written to file in the view
–œ‡°±·;˛ˇ ˛ˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇRoot Entryˇˇˇˇˇˇˇˇ#Workbookˇˇˇˇˇˇˇˇˇˇˇˇ˛ˇˇˇ˝ˇˇˇ˛ˇˇˇ ˛ˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇˇ
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Same part of the excel when downloaded
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Usually instead of putting the file in the model I write it directly in the response.
The following code is for xlsx format, but the concept is the same for previous versions of excel.
This endpoint is accepting a JSON which will be mapped to MyPojo.
#RequestMapping(value = "exportToExcel", method = RequestMethod.POST)
public #ResponseBody HttpEntity<byte[]> generateExcel(#Valid #RequestBody final MyPojo data) throws IOException {
final File file = File.createTempFile("MyExcelReport", "xlsx");
file.deleteOnExit();
final Path path = file.toPath();
try (final FileOutputStream fileOut = new FileOutputStream(file)) {
try (final XSSFWorkbook workbook = new XSSFWorkbook()) {
final XSSFSheet sheet = workbook.createSheet(SHEET_NAME);
//fill your excel sheets
workbook.write(fileOut);
final byte[] byteArray = Files.readAllBytes(path);
final HttpHeaders header = new HttpHeaders();
header.setContentType(new MediaType("application", "vnd.openxmlformats-officedocument.spreadsheetml.sheet"));
header.set("Content-Disposition", "inline; filename=MyExcelReport.xlsx");
header.setContentLength(byteArray.length);
return new HttpEntity<>(byteArray, header);
} catch (final Exception e) {
LOG.error("Error during creation of excel report", e);
throw e;
} finally {
if (path != null) {
try {
Files.delete(path);
} catch (final IOException e) {
LOG.error("Unable to delete file:" + path.toString(), e);
}
}
}
}
}
Also if you are using a frontend framework like angular you have to properly setup the response type (https://stackoverflow.com/a/52703842/3657208)
I am using CommonsMultipartResolver to upload a word/pdf file into postgres database, while uploading the file I have printed the byte[] array using file.getBytes(), it showing like
bytes==========================[B#6b02547c
the file is being upload but when I download the file I am getting the following error from ms-word: "The file abc.docx cannot be opened because there are problems with contents". please help me to solve this problem.
#SuppressWarnings({ "unused", "static-access" })
#RequestMapping( value="/RegisterCandidate" , method = RequestMethod.POST)
private String RegisterCandidate(HttpServletRequest request,
HttpServletResponse response,
#RequestParam CommonsMultipartFile[] fileUpload ) throws Exception{
System.out.println("In method");
String email = request.getParameter("email");
System.out.println("email==============="+email);
String Password = request.getParameter("password");
String usr_name = request.getParameter("name");
String mobile_no = request.getParameter("mobile_no");
Date dateentry = new Date();
java.sql.Timestamp entry_date = new Timestamp(dateentry.getTime());
Users_Pojo usr = new Users_Pojo();
if (fileUpload != null && fileUpload.length > 0) {
for (CommonsMultipartFile aFile : fileUpload){
usr.setFilename(aFile.getOriginalFilename());
usr.setFile_data(aFile.getBytes());
System.out.println("aFile.getBytes()======"+aFile.getBytes());
System.out.println("aFile.getInputStream()======"+aFile.getInputStream());
System.out.println("aFile.getStorageDescription()======"+aFile.getStorageDescription());
System.out.println("aFile.getSize();======"+aFile.getSize());
System.out.println("aFile.getContentType();==="+aFile.getContentType());/* */
}
}
usr.setUc_password("ex123");
usr.setUc_name(email);
usr.setUc_contact_person(email);
usr.setUc_phone_no(BigInteger.valueOf(Long.parseLong(mobile_no)));
usr.setUc_email_id(email);
usr.setUc_type_id(1);
usr.setUc_active(1);
usr.setValid_from(null);
usr.setValid_to(null);
usr.setDesignation("jobseekar");
usr.setIp_address("164.100.200.179");
usr.setUser_location(1);
usr.setEntry_date(entry_date);
scm_service.save(usr, email);
/*System.out.println("email==="+email);
System.out.println("Password==="+Password);
System.out.println("usr filename==="+usr.getFilename());*/
return "success";
//return "redirect:Login.html";
}
Configuration:
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="maxUploadSize" value="2000000" />
</bean>
downloading using :
#RequestMapping(value = "/download",method = RequestMethod.GET)
public void getAttachmenFromDatabase( HttpServletRequest request,HttpServletResponse response){
response.setContentType("application/vnd.ms-word");
String resume_id = request.getParameter("resume_id");
long attachid = Long.parseLong(resume_id);
try {
Users_Pojo file_attachment = (Users_Pojo) scm_service.getFiles(attachid);
System.out.println("file_attachment.getFilename()======="+file_attachment.getFile_data());
response.setHeader("Content-Disposition", "inline; filename=\""+ file_attachment.getFilename() +"\"");
response.setContentLength(file_attachment.getFile_data().length);
FileCopyUtils.copy(file_attachment.getFile_data(), response.getOutputStream());
response.flushBuffer();
} catch (IOException e) {
e.printStackTrace();
}
}
How can I retrieve and display images from a database in a JSP page?
Let's see in steps what should happen:
JSP is basically a view technology which is supposed to generate HTML output.
To display an image in HTML, you need the HTML <img> element.
To let it locate an image, you need to specify its src attribute.
The src attribute needs to point to a valid http:// URL and thus not a local disk file system path file:// as that would never work when the server and client run at physically different machines.
The image URL needs to have the image identifier in either the request path (e.g. http://example.com/context/images/foo.png) or as request parameter (e.g. http://example.com/context/images?id=1).
In JSP/Servlet world, you can let a Servlet listen on a certain URL pattern like /images/*, so that you can just execute some Java code on specific URL's.
Images are binary data and are to be obtained as either a byte[] or InputStream from the DB, the JDBC API offers the ResultSet#getBytes() and ResultSet#getBinaryStream() for this, and JPA API offers #Lob for this.
In the Servlet you can just write this byte[] or InputStream to the OutputStream of the response the usual Java IO way.
The client side needs to be instructed that the data should be handled as an image, thus at least the Content-Type response header needs to be set as well. You can obtain the right one via ServletContext#getMimeType() based on image file extension which you can extend and/or override via <mime-mapping> in web.xml.
That should be it. It almost writes code itself. Let's start with HTML (in JSP):
<img src="${pageContext.request.contextPath}/images/foo.png">
<img src="${pageContext.request.contextPath}/images/bar.png">
<img src="${pageContext.request.contextPath}/images/baz.png">
You can if necessary also dynamically set src with EL while iterating using JSTL:
<c:forEach items="${imagenames}" var="imagename">
<img src="${pageContext.request.contextPath}/images/${imagename}">
</c:forEach>
Then define/create a servlet which listens on GET requests on URL pattern of /images/*, the below example uses plain vanilla JDBC for the job:
#WebServlet("/images/*")
public class ImageServlet extends HttpServlet {
// content=blob, name=varchar(255) UNIQUE.
private static final String SQL_FIND = "SELECT content FROM Image WHERE name = ?";
#Resource(name="jdbc/yourDB") // For Tomcat, define as <Resource> in context.xml and declare as <resource-ref> in web.xml.
private DataSource dataSource;
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String imageName = request.getPathInfo().substring(1); // Returns "foo.png".
try (Connection connection = dataSource.getConnection(); PreparedStatement statement = connection.prepareStatement(SQL_FIND)) {
statement.setString(1, imageName);
try (ResultSet resultSet = statement.executeQuery()) {
if (resultSet.next()) {
byte[] content = resultSet.getBytes("content");
response.setContentType(getServletContext().getMimeType(imageName));
response.setContentLength(content.length);
response.getOutputStream().write(content);
} else {
response.sendError(HttpServletResponse.SC_NOT_FOUND); // 404.
}
}
} catch (SQLException e) {
throw new ServletException("Something failed at SQL/DB level.", e);
}
}
}
That's it. In case you worry about HEAD and caching headers and properly responding on those requests, use this abstract template for static resource servlet.
See also:
How should I connect to JDBC database / datasource in a servlet based application?
How to upload an image and save it in database?
Simplest way to serve static data from outside the application server in a Java web application
I suggest you address that as two problems. There are several questions and answer related to both.
How to load blob from MySQL
See for instance Retrieve image stored as blob
How to display image dynamically
See for instance Show thumbnail dynamically
I've written and configured the code in JSP using Oracle database.
Hope it will help.
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.http.HttpSession;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class displayfetchimage
*/
#WebServlet("/displayfetchimage")
public class displayfetchimage extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public displayfetchimage() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
* response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// TODO Auto-generated method stub
Statement stmt = null;
String sql = null;
BufferedInputStream bin = null;
BufferedOutputStream bout = null;
InputStream in = null;
response.setContentType("image/jpeg");
ServletOutputStream out;
out = response.getOutputStream();
Connection conn = employee.DbConnection.getDatabaseConnection();
HttpSession session = (HttpSession) request.getSession();
String ID = session.getAttribute("userId").toString().toLowerCase();
try {
stmt = conn.createStatement();
sql = "select user_image from employee_data WHERE username='" + ID + "' and rownum<=1";
ResultSet result = stmt.executeQuery(sql);
if (result.next()) {
in = result.getBinaryStream(1);// Since my data was in first column of table.
}
bin = new BufferedInputStream(in);
bout = new BufferedOutputStream(out);
int ch = 0;
while ((ch = bin.read()) != -1) {
bout.write(ch);
}
} catch (SQLException ex) {
Logger.getLogger(displayfetchimage.class.getName()).log(Level.SEVERE, null, ex);
} finally {
try {
if (bin != null)
bin.close();
if (in != null)
in.close();
if (bout != null)
bout.close();
if (out != null)
out.close();
if (conn != null)
conn.close();
} catch (IOException | SQLException ex) {
System.out.println("Error : " + ex.getMessage());
}
}
}
// response.getWriter().append("Served at: ").append(request.getContextPath());
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
* response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Statement stmt = null;
String sql = null;
BufferedInputStream bin = null;
BufferedOutputStream bout = null;
InputStream in = null;
response.setContentType("image/jpeg");
ServletOutputStream out;
out = response.getOutputStream();
Connection conn = employee.DbConnection.getDatabaseConnection();
HttpSession session = (HttpSession) request.getSession();
String ID = session.getAttribute("userId").toString().toLowerCase();
try {
stmt = conn.createStatement();
sql = "select user_image from employee_data WHERE username='" + ID + "' and rownum<=1";
ResultSet result = stmt.executeQuery(sql);
if (result.next()) {
in = result.getBinaryStream(1);
}
bin = new BufferedInputStream(in);
bout = new BufferedOutputStream(out);
int ch = 0;
while ((ch = bin.read()) != -1) {
bout.write(ch);
}
} catch (SQLException ex) {
Logger.getLogger(displayfetchimage.class.getName()).log(Level.SEVERE, null, ex);
} finally {
try {
if (bin != null)
bin.close();
if (in != null)
in.close();
if (bout != null)
bout.close();
if (out != null)
out.close();
if (conn != null)
conn.close();
} catch (IOException | SQLException ex) {
System.out.println("Error : " + ex.getMessage());
}
}
}
}
Try to flush and close the output stream if it does not display.
Blob image = rs.getBlob(ImageColName);
InputStream in = image.getBinaryStream();
// Output the blob to the HttpServletResponse
response.setContentType("image/jpeg");
BufferedOutputStream o = new BufferedOutputStream(response.getOutputStream());
byte by[] = new byte[32768];
int index = in.read(by, 0, 32768);
while (index != -1) {
o.write(by, 0, index);
index = in.read(by, 0, 32768);
}
o.flush();
o.close();
I used SQL SERVER database and so the answer's code is in accordance. All you have to do is include an <img> tag in your jsp page and call a servlet from its src attribute like this
<img width="200" height="180" src="DisplayImage?ID=1">
Here 1 is unique id of image in database and ID is a variable. We receive value of this variable in servlet. In servlet code we take the binary stream input from correct column in table. That is your image is stored in which column. In my code I used third column because my images are stored as binary data in third column. After retrieving input stream data from table we read its content in an output stream so it can be written on screen. Here is it
import java.io.*;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.*;
import javax.servlet.http.*;
import model.ConnectionManager;
public class DisplayImage extends HttpServlet {
public void doGet(HttpServletRequest request,HttpServletResponse response)
throws IOException
{
Statement stmt=null;
String sql=null;
BufferedInputStream bin=null;
BufferedOutputStream bout=null;
InputStream in =null;
response.setContentType("image/jpeg");
ServletOutputStream out;
out = response.getOutputStream();
Connection conn = ConnectionManager.getConnection();
int ID = Integer.parseInt(request.getParameter("ID"));
try {
stmt = conn.createStatement();
sql = "SELECT * FROM IMAGETABLE WHERE ID="+ID+"";
ResultSet result = stmt.executeQuery(sql);
if(result.next()){
in=result.getBinaryStream(3);//Since my data was in third column of table.
}
bin = new BufferedInputStream(in);
bout = new BufferedOutputStream(out);
int ch=0;
while((ch=bin.read())!=-1)
{
bout.write(ch);
}
} catch (SQLException ex) {
Logger.getLogger(DisplayImage.class.getName()).log(Level.SEVERE, null, ex);
}finally{
try{
if(bin!=null)bin.close();
if(in!=null)in.close();
if(bout!=null)bout.close();
if(out!=null)out.close();
if(conn!=null)conn.close();
}catch(IOException | SQLException ex){
System.out.println("Error : "+ex.getMessage());
}
}
}
}
After the execution of your jsp or html file you will see the image on screen.
You can also create custom tag for displaying image.
1) create custom tag java class and tld file.
2) write logic to display image like conversion of byte[] to string by Base64.
so it is used for every image whether you are displaying only one image or multiple images in single jsp page.
I am getting null for one of the selected column with IterableCSVToBean<MessageFileExtractHeader>
DTO Classe:
public class MessageFileExtractHeader implements Serializable {
private static final long serialVersionUID = -3052197544136826142L;
private String mesgid;
private String mesg_type;
// getters and setters
Main Class:
public class FileExtraction {
public static void main(String[] args) throws IOException, IllegalAccessException, InvocationTargetException, InstantiationException, IntrospectionException, CsvBadConverterException, CsvDataTypeMismatchException, CsvRequiredFieldEmptyException, CsvConstraintViolationException {
Properties prop = new Properties();
ExtractFieldUtils efUtils= new ExtractFieldUtils();
MessageFileExtractHeader msgFilxtractRecord = null;
try {
InputStream inputStream =
SAADumpFileExtraction.class.getClassLoader().getResourceAsStream("config.properties");
prop.load(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
String fileDirectory= prop.getProperty("file.directory");
//get the filenames
String mesgfilename= fileDirectory+prop.getProperty("mesg.file.name");
//get the headers
String mesgheader= fileDirectory+prop.getProperty("mesg.file.header.fields");
int msgskiplines=1;
CSVReader reader = null;
try {
reader = new CSVReader(new FileReader(mesgfilename));
Map<String, String> msgmapping = efUtils.getMapping(mesgheader);
HeaderColumnNameTranslateMappingStrategy<MessageFileExtractHeader> strategy = new HeaderColumnNameTranslateMappingStrategy<MessageFileExtractHeader>();
strategy.setType(MessageFileExtractHeader.class);
strategy.setColumnMapping(msgmapping);
IterableCSVToBean<MessageFileExtractHeader> msgCTBIterator= new IterableCSVToBean<MessageFileExtractHeader>(reader, strategy, null);
Iterator<MessageFileExtractHeader> mesgIterator= msgCTBIterator.iterator();
while(mesgIterator.hasNext()){
msgFilxtractRecord = mesgIterator.next();
System.out.println(msgFilxtractRecord);
//
}} finally {
reader.close();
}
}
}
Output:
MessageFileExtractHeaders [mesgid=null, mesg_type=081]
Please suggest me good solution to get the mesgid.
Please send an short sample of your csv file (header and one line) and the value of your header property.
My guess is there is a type in either the csv header, the headers in the property or both and it does not match what is in the DTO (mesgid). Because of that it will not be populated.