I have been trying to upload an image into the table but no joy at all.
I have used a store procedure and encrypted my connection strings in the appsettings and use data layer to access the objects.
string FilePath = FileUpload1.PostedFile.FileName;
string FileName = Path.GetFileName(FilePath);
string ext = Path.GetExtension(FileName);
string ContentType = string.Empty;
switch (ext)
{
case ".jpg":
ContentType = "Image/jpg";
break;
case ".png":
ContentType = "Image/png";
break;
case ".gif":
ContentType = "Image/gif";
break;
}
if (ContentType != string.Empty)
{
Stream fs = FileUpload1.PostedFile.InputStream;
BinaryReader br = new BinaryReader(fs);
Byte[] bytes = br.ReadBytes((Int32)fs.Length);
SqlCommand _SqlCom = new SqlCommand("sp_InsFoto");
_SqlCom.Parameters.Add("#imgName", SqlDbType.VarChar).Value = FileName;
_SqlCom.Parameters.Add("#Imgdata", SqlDbType.Binary).Value =bytes;
_SqlCom.Parameters.Add("#imgContentType", SqlDbType.VarChar).Value =ContentType;
obj.ExecuteNonQuery(ref _SqlCom);
And I have the store procedure as stated below
CREATE PROCEDURE [dbo].[sp_InsFoto]
(
#ImgName varchar(50)
,#ImgData varbinary(MAX)
,#ImgContentType varchar(50)
)
AS INSERT INTO tbl_Fotos
(
ImgName
,ImgData
,ImgContentType
)
VALUES
(
#ImgName
,#ImgData
,#ImgContentType
)
**UPLOADING IMAGE AND SAVING PATH IN THE DATABASE
________________________________________________________________________________________
<%# page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<div>
<h3> Choose File to Upload in Server </h3>
<form action="Recent" method="post" enctype="multipart/form-data">
<input type="file" name="file" />
<input type="submit" value="upload" />
</form>
</div>
</body>
</html>
____________________________________________________________________________________________
import java.sql.*;
import java.io.*;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import java.util.Hashtable;
import java.util.List;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.ParameterParser;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
/**
* Servlet implementation class Recent
*/
#WebServlet("/Recent")
#MultipartConfig
public class Recent extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public Recent() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
Sample s1=new Sample();
final String UPLOAD_DIRECTORY = "/home/pradeep/Documents/pradeep/WebContent/Images";
if(ServletFileUpload.isMultipartContent(request)){
try {
List<FileItem> multiparts = new
ServletFileUpload(new DiskFileItemFactory()).parseRequest(request);
for(FileItem item : multiparts){
if(!item.isFormField())
{
String name = new File(item.getName()).getName();
item.write( new File(UPLOAD_DIRECTORY + File.separator + name));
String Path= "/home/pradeep/Documents/pradeep/WebContent/Images/" +name;
s1.connecting(Path);
}
}
request.setAttribute("message", "File Uploaded Successfully");
} catch (Exception ex) {
request.setAttribute("message", "File Upload Failed due to " + ex);
}
}else{
request.setAttribute("message",
"Sorry this Servlet only handles file upload request");
}
request.getRequestDispatcher("/Result.jsp").forward(request, response);
}
}
__________________________________________________________________________________________
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import dbconnections.Connections;
public class Sample {
Connections con=new Connections();
public void connecting(String Path)
{
Connection conn=con.Connect();
PreparedStatement pst;
String query="INSERT INTO Student1 (Path) values (?)";
try {
pst=conn.prepareStatement(query);
pst.setString(1,Path);
pst.executeUpdate();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// TODO Auto-generated method stub
}
}
Name of parameters in your code should exactly match names defined in stored procedure, so in the code below change #imgName to #ImgName and #imgContentType to #ImgContentType:
SqlCommand _SqlCom = new SqlCommand("sp_InsFoto");
_SqlCom.Parameters.Add("#imgName", SqlDbType.VarChar).Value = FileName;
_SqlCom.Parameters.Add("#Imgdata", SqlDbType.Binary).Value =bytes;
_SqlCom.Parameters.Add("#imgContentType", SqlDbType.VarChar).Value =ContentType;
obj.ExecuteNonQuery(ref _SqlCom);
Related
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'm new to htmlunit (2.23) and I can't get this test to work:
I'm getting this ClassCastException thrown out of HtmlUnit and I don't know if it is a bug, or if I am doing something wrong.
java.lang.ClassCastException: com.gargoylesoftware.htmlunit.TextPage cannot be cast to com.gargoylesoftware.htmlunit.html.HtmlPage
at com.gargoylesoftware.htmlunit.WebClient.makeWebResponseForJavaScriptUrl(WebClient.java:1241)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:375)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:304)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:451)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:436)
at org.wyttenbach.dale.mlec.OutageTest.test(OutageTest.java:46)
...
The code
import java.awt.Desktop;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URI;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.junit.Assert;
import org.junit.Test;
import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;
import com.gargoylesoftware.htmlunit.JavaScriptPage;
import com.gargoylesoftware.htmlunit.NicelyResynchronizingAjaxController;
import com.gargoylesoftware.htmlunit.Page;
import com.gargoylesoftware.htmlunit.TextPage;
import com.gargoylesoftware.htmlunit.WebClient;
import com.gargoylesoftware.htmlunit.html.DomElement;
import com.gargoylesoftware.htmlunit.html.HtmlPage;
public class OutageTest {
private static final String SITE_URL = "https://ebill.mlecmn.net/woViewer/";
private static final String OUTAGE_MAP_URL = SITE_URL + "mapviewer.html?config=Outage+Web+Map";
#Test
public void test() throws FailingHttpStatusCodeException, MalformedURLException, IOException {
try (final WebClient webClient = new WebClient()) {
webClient.waitForBackgroundJavaScript(20000);
webClient.setAjaxController(new NicelyResynchronizingAjaxController());
webClient.getOptions().setUseInsecureSSL(true);
Map<String, Page> urls = new HashMap<String, Page>();
LinkedList<String> urlsToVisit = new LinkedList<String>();
urlsToVisit.add(OUTAGE_MAP_URL);
while (!urlsToVisit.isEmpty()) {
String url = urlsToVisit.remove();
if (urls.containsKey(url)) {
continue;
}
Page page = webClient.getPage(url);
urls.put(url, page);
if (page instanceof HtmlPage) {
HtmlPage page2 = (HtmlPage) page;
System.err.println("================================================================");
System.err.println(page2.asXml());
System.err.println("================================================================");
Assert.assertFalse("Outage in Nordland township: " + url, page2.asText().contains("Nordland"));
urlsToVisit.addAll(extractLinks(page2));
} else if (page instanceof JavaScriptPage) {
JavaScriptPage page2 = (JavaScriptPage) page;
Assert.assertFalse("Outage in Nordland township: " + url, page2.getContent().contains("Nordland"));
} else if (page instanceof TextPage) {
TextPage page2 = (TextPage) page;
Assert.assertFalse("Outage in Nordland township: " + url, page2.getContent().contains("Nordland"));
} else {
System.err.println(String.format("%s => %s", url, page.getClass().getName()));
}
}
} catch (AssertionError e) {
reportOutage();
throw e;
}
}
private Collection<String> extractLinks(HtmlPage page) {
List<String> links = new ArrayList<String>();
for (DomElement x : page.getElementsByTagName("script")) {
String src = x.getAttribute("src");
if (!src.contains(":")) {
src = SITE_URL + src;
System.err.println("script src="+src);
}
links.add(src);
}
for (DomElement x : page.getElementsByTagName("link")) {
String href = x.getAttribute("href");
if (!href.contains(":")) {
href = SITE_URL + href;
System.err.println("link href="+href);
}
links.add(href);
}
// Causes ClassCastException com.gargoylesoftware.htmlunit.TextPage cannot be cast to com.gargoylesoftware.htmlunit.html.HtmlPage
//at com.gargoylesoftware.htmlunit.WebClient.makeWebResponseForJavaScriptUrl(WebClient.java:1241)
for (DomElement x : page.getElementsByTagName("iframe")) {
String src = x.getAttribute("src");
if (!src.contains(":")) {
src = SITE_URL + src;
System.err.println("iframe src="+src);
}
links.add(src);
}
return links;
}
private void reportOutage() {
try {
Desktop.getDesktop().browse(new URI(OUTAGE_MAP_URL));
} catch (Exception e) {
e.printStackTrace();
}
}
}
More or less yes - but i have to do a more deeper analysis.
But there is some hope for you ;-)
Your code tries to extract urls from a given web page. During the process you are adding the url 'javascript:""' to your list of urls to be processes. This url results in this class cast exception. If you do not add this url to the list, the test is working (at least for me).
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 spent 10 years writing ASP/Ajax and MUST switch to JAVA.
I am starting very simple script so as to understand the concepts clearly before diving into more complex stuff. I am using Tomcat 7, Servlet 3
The problem is. The servlet is called successfully but the form data is not transferred
This is the edited servlet (Main.java)
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class Main
*/
#WebServlet("/Main")
public class Main extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public Main() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//int ids;
//String ids;
//response.setContentType("text/html;charset=UTF-8");
//PrintWriter out = response.getWriter();
String val = request.getParameter("id");
String name = request.getParameter("name");
//response.getWriter().write(val);
//response.getWriter().write("::");
//response.getWriter().write(name);
response.setContentType("text/plain");
response.setCharacterEncoding("UTF-8");
response.getWriter().write(val +" "+ name);
//System.out.print(val);
//if(val != null){
// //ids = Integer.parseInt(val);
// //out.print(ids);
// out.print(val);
//}
}
}
This is the edited JSP (Main.jsp):
<!DOCTYPE html>
<html lang="en">
<head>
<title>SO question 4112686</title>
<script src="http://code.jquery.com/jquery-latest.min.js"></script>
<script>
$.ajaxSetup({ cache: false });
$(document).ready(function() {
$('#submit').click(function(event) {
var form = (event.target.form),
url = "/Main"
+ "?lName=" + escape(form.elements.lName.text)
+ "&fName=" + escape(form.elements.fName.text);
$.get(url, function(getData) {
$('#somediv').text(getData);
});
});
});
</script>
</head>
<body>
<form id="Main" action="Main" method="post">
<h4>AJAX Demo using Jquery in JSP and Servlet</h4>
Enter your Name:
<br/><input type="text" id="fName" name="fName"/>
<br/><input type="text" id="lName" name="lName"/>
<br/><input type="submit" id="submit" value="Ajax Submit"/>
<br/>
</form>
<div id="somediv">....</div>
</body>
</html>
Edit: If the form data is not transferred, that's because you are not sending it to the server. A GET request means you need lName=abc&fName=def appended to the URL:
<script>
$.ajaxSetup({ cache: false });
$(document).ready(function() {
$('#submit').click(function(event) {
var form = (event.target.form),
url = "/SomeServlet"
+ "?lName=" + escape(form.elements.lName.text)
+ "&fName=" + escape(form.elements.fName.text);
$.get(url, function(getData) {
$('#somediv').text(getData);
});
});
});
</script>
Since i've asked my last question (which still unanswered) i continued searching for a solution and lastly i found this topic which i think can help achieve what i want.
So , i tried that solution (which itself is a workaround) but it still didn't work for me.
Here is the code, it s all just a test for this issue :
the index.xhtml :
<?xml version="1.0" encoding="ISO-8859-1" ?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:p="http://primefaces.org/ui"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:c="http://java.sun.com/jsp/jstl/core">
<h:head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
<title>dyn add comps test </title>
</h:head>
<body>
<h:form id="form1">
<!-- once this first commandLink is clisked it will generate another commandlink below it -->
<h:commandLink value="cliick me">
<f:ajax event="click" listener="#{myBean.firstcmdLinkListenerHandler}"/>
</h:commandLink>
</h:form>
</body>
</html>
The managed Bean : MyBean.java
package mybeans;
import javax.el.ExpressionFactory;
import javax.el.MethodExpression;
import javax.faces.application.Application;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import javax.faces.component.UIComponent;
import javax.faces.component.html.HtmlCommandLink;
import javax.faces.context.FacesContext;
import javax.faces.event.AjaxBehaviorEvent;
import javax.faces.event.BehaviorEvent;
import org.primefaces.component.behavior.ajax.AjaxBehaviorListenerImpl;
import org.primefaces.context.RequestContext;
#ManagedBean
#SessionScoped
public class MyBean {
public void handleClose(AjaxBehaviorEvent abe){
System.out.println("!!!-->>>>> the Ajax Behaviour Works !!!!! ");
}
public void reLoadCityList( BehaviorEvent event ){
System.out.println("!!!-->>>>> the reLoadCityList method Works !!!!! ");
}
public void firstcmdLinkListenerHandler(AjaxBehaviorEvent abe){
System.out.println("firstcmdLinkListenerHandleris running ! ");
FacesContext fc = FacesContext.getCurrentInstance();
Application application = fc.getApplication();
ExpressionFactory ef = fc.getApplication().getExpressionFactory();
UIComponent form1 = fc.getViewRoot().findComponent("form1");
if(form1!=null){
//Creating the commandLink
HtmlCommandLink mynewcmdlink = (HtmlCommandLink)application.createComponent(HtmlCommandLink.COMPONENT_TYPE);
mynewcmdlink.setId("mynewcmdlink");
mynewcmdlink.setValue("clickme2!!");
MyAjaxBehavior pajax = new MyAjaxBehavior();
Class[] par = new Class[1];
par[0] = BehaviorEvent.class;
//par[0] = AjaxBehaviorEvent.class; (*)
//pajax.setListener( myCreateMetExpression( "reLoadCityList", true, //void.class, par ) );
//i tried with both AjaxBehaviorEvent and BehaviorEvent as in (*)
//MethodExpression me = ef.createMethodExpression( //fc.getELContext(), "#{myBean.handleClose}", void.class, par);
MethodExpression me = ef.createMethodExpression( fc.getELContext(), "#{myBean.reLoadCityList}", void.class, par);
//pajax.setListener(me); //i've tried with this too but it wasn't sucesseful
pajax.addAjaxBehaviorListener( new AjaxBehaviorListenerImpl( me ) );
pajax.setProcess( "#this" );
mynewcmdlink.addClientBehavior( "change", pajax );
//adding thecommanLink to the form
form1.getChildren().add(mynewcmdlink);
//Refreshing the form to see the added commandLink :
RequestContext context = RequestContext.getCurrentInstance();
context.update("form1");
context.update("form1:foo");
}else
System.out.println("form1 is null!!");
}
and the MyAjaxBehavior.java used as the workaround in the primefaces forum article:
package mybeans;
import java.util.HashMap;
import javax.el.ELContext;
import javax.el.MethodExpression;
import javax.faces.component.UIComponentBase;
import javax.faces.context.FacesContext;
import javax.faces.event.AbortProcessingException;
import javax.faces.event.BehaviorEvent;
import org.primefaces.component.behavior.ajax.AjaxBehavior;
public class MyAjaxBehavior extends AjaxBehavior {
#Override
public Object saveState(FacesContext context) {
HashMap<String, Object> map;
map = new HashMap<String, Object>();
map.put("update", getUpdate());
map.put("process", getProcess());
map.put("oncomplete", getOncomplete());
map.put("onerror", getOnerror());
map.put("onsuccess", getOnsuccess());
map.put("onstart", getOnstart());
map.put("listener", getListener());
if (initialStateMarked())
return null;
return UIComponentBase.saveAttachedState(context, map);
}
#SuppressWarnings("unchecked")
#Override
public void restoreState(FacesContext context, Object state) {
if (state != null) {
HashMap<String, Object> map;
map = (HashMap<String, Object>) UIComponentBase
.restoreAttachedState(context, state);
setUpdate((String) map.get("update"));
setProcess((String) map.get("process"));
setOncomplete((String) map.get("oncomplete"));
setOnerror((String) map.get("onerror"));
setOnsuccess((String) map.get("onsuccess"));
setOnstart((String) map.get("onstart"));
setListener((MethodExpression) map.get("listener"));
}
}
#Override
public void broadcast(BehaviorEvent event) throws AbortProcessingException {
ELContext eLContext = FacesContext.getCurrentInstance().getELContext();
// Backward compatible implementation of listener invocation
if (getListener() != null) {
try {
getListener().invoke(eLContext, new Object[] { event });
} catch (IllegalArgumentException exception) {
getListener().invoke(eLContext, new Object[0]);
}
}
}
}
Do something like this
Panel tp = new Panel();
FacesContext fc = FacesContext.getCurrentInstance();
ExpressionFactory ef = fc.getApplication().getExpressionFactory();
MethodExpression me = ef.createMethodExpression(fc.getELContext(), "#{myView.closeIt}", null, new Class<?>[]{BehaviorEvent.class});
AjaxBehavior ajaxBehavior = (AjaxBehavior) fc.getApplication().createBehavior(AjaxBehavior.BEHAVIOR_ID);
ajaxBehavior.setProcess("#this");
ajaxBehavior.addAjaxBehaviorListener(new AjaxBehaviorListenerImpl(me, me));
tp.addClientBehavior("close", ajaxBehavior);
component.getChildren().add(tp);
myView.closeIt()
public void closeIt(CloseEvent ce){
Panel p = (Panel) ce.getComponent();
System.out.println("Do what ever you want");
}