I have a serlvet to upload file ... It work on my server, i upload to "http://localhost:8084/TestAmazon" and it work ... but we deploy my web application to host and upload file it not work ... please help me
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String relativeWebPath = "/image";
String absoluteFilePath = getServletContext().getRealPath(relativeWebPath);
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(absoluteFilePath + File.separator + name));
}
}
request.setAttribute("message", "File Uploaded Successfully");
} catch (Exception e) {
request.setAttribute("message", "File Upload Failed due to " + e);
}
} else {
request.setAttribute("message",
"Sorry this Servlet only handles file upload request");
}
request.getRequestDispatcher("result.jsp").forward(request, response);
}
i got an error:
exception
javax.servlet.ServletException: Servlet execution threw an exception
root cause
java.lang.NoSuchMethodError: org.apache.tomcat.util.http.fileupload.servlet.ServletFileUpload.parseRequest(Ljavax/servlet/http/HttpServletRequest;)Ljava/util/List;
sample.ProcessServlet.doPost(ProcessServlet.java:73)
javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
Related
I've a servlet that checks username and password from database.
#Override
protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mvs_user", "root", "pass");
if (req.getParameter("usrnm") != null && req.getParameter("pwd") != null) {
String username = req.getParameter("usrnm");
String userpass = req.getParameter("pwd");
String strQuery = "select * from user where username='" + username + "' and password='" + userpass + "'";
System.out.println(strQuery);
Statement st = conn.createStatement();
ResultSet rs = st.executeQuery(strQuery);
if (rs.next()) {
req.getSession(true).setAttribute("username", rs.getString(2));
res.sendRedirect("adminHome.jsp");
} else {
res.sendRedirect("index.jsp");
}
} else {
res.sendRedirect("login.jsp");
}
conn.close();
} catch (Exception e) {
e.printStackTrace();
}
}
The problem is the browser only displays a blank page and yet I expect it to display "Hello World" in the redirected page. Where could the problem be? Please help me troubleshoot.
You need to properly handle exceptions. You should not only print them but really throw them.
Replace
} catch (Exception e) {
e.printStackTrace(); // Or System.out.println(e);
}
by
} catch (Exception e) {
throw new ServletException("Login failed", e);
}
With this change, you will now get a normal error page with a complete stacktrace about the cause of the problem. You can of course also just dig in the server logs to find the stacktrace which you just printed instead of rethrowed.
There are several possible causes of your problem. Maybe a ClassNotFoundException or a SQLException. All which should be self-explaining and googlable.
See also:
How should I connect to JDBC database / datasource in a servlet based application?
How to install JDBC driver in Eclipse web project without facing java.lang.ClassNotFoundexception
The infamous java.sql.SQLException: No suitable driver found
Unrelated to the concrete problem, your JDBC code is prone to resource leaking and SQL injection attacks. Do a research on that as well and fix accordingly.
I implemented servlet, that creates XLS file. I am making a request from UI (GWT, RequestBuilder). I get the response, but is it possible to get ready file (with auto "save as" dialog box)?
Should I somehow set headers or something?
Here is my code:
Request implementation
RequestBuilder rb = new RequestBuilder(RequestBuilder.GET, GWT.getModuleBaseURL() + "downloadLimitsFile");
try {
rb.setHeader("Content-type", "text/html");
Request response = rb.sendRequest("", new RequestCallback() {
public void onError(Request request, Throwable exception) {
Window.alert("fail");
}
public void onResponseReceived(Request request, Response response) {
Window.alert("file downloaded " + response.getText());
}
});
} catch (RequestException e) {
Window.alert("Failed to send the request: " + e.getMessage());
}
My servlet implementation
public void handleRequest(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
response.setHeader("Content-Disposition", "attachment; filename=File.xls");
HSSFWorkbook workbook = new HSSFWorkbook();
try {
workbook = fileExporter.prepareExcellFile();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} catch (ParseException e) {
e.printStackTrace();
}
response.setStatus(HttpServletResponse.SC_OK);
OutputStream out = response.getOutputStream();
workbook.write(out);
out.flush();
out.close();
response.flushBuffer();
}
It was working fine (auto file download) when I was using eg. Anchor with servlet URL, but I have to use RequestBuilder now to make a request.
Can someone help?
I am afraid it is not possible, at least you can use a third party library.
Adding the header "Content-Disposition" won't work.
To accomplish:
Upload a file from my local to server using an applet and servlet using apache fileupload jar.
Tried:
I have used a simple jsp, with a browse button and posted the action to my servlet (where I used apache fileupload). I was successful in uploading the file to the server.
Issue:
I am trying to upload a file, from my local machine, using an applet. I do not want to manually select files, instead upload files that are present in a specific folder. For now I have hardcoded the folder. I am able to look at the folder and get the list of files I want to upload.
Also, I have successfully established a connection from my applet to servlet.
Issue arises at the upload.parseRequest(request) in the servlet. I'm thinking its because the applet cannot post to servlet's request object.
Also, I have set the request type to multipart/form-data in my applet.
Right now, I am trying to pass the absolute path of the file to servlet and upload.
I have seen other posts where byte stream data is passed from applet to servlet, but the servlet uses the traditional File.write.
For me, it is mandatory to achieve this using apache fileupload.
Please suggest on how to pass a file/file path from applet to servlet, where the upload is handled by apache fileupload.
Below are my FileUploadHandler (where the HTTP requests are handled) and FileUpload(which is my applet)
Below is my FileUpload Handler:
#WebServlet(name = "FileUploadHandler", urlPatterns = { "/upload" })
#MultipartConfig
public class FileUploadHandler extends HttpServlet {
String uploadFolder ="";
#Override
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
System.out.println("doPost-servlet URL is: "
+ request.getRequestURL());
try {
uploadFolder = fileToUpload(request);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
uploadFolder = getServletContext().getRealPath("")+ File.separator;
// Create a factory for disk-based file items
DiskFileItemFactory factory = new DiskFileItemFactory();
// Create a new file upload handler
ServletFileUpload upload = new ServletFileUpload(factory);
// process only if its multipart content
if (ServletFileUpload.isMultipartContent(request)) {
System.out.println("Yes, it is a multipart request...");
try {
List<FileItem> multiparts = upload.parseRequest(request);
System.out.println("Upload.parseRequest success !");
for (FileItem item : multiparts) {
if (!item.isFormField()) {
String name = new File(item.getName()).getName();
item.write(new File(uploadFolder + File.separator
+ name));
}
}
System.out.println("File uploaded to server !");
// File uploaded successfully
request.setAttribute("message", "File Uploaded Successfully");
} catch (Exception ex) {
request.setAttribute("message", "File Upload Failed due to "
+ ex);
}
} if(!ServletFileUpload.isMultipartContent(request)){
throw new ServletException("Content type is not multipart/form-data");
}
doGet(request, response);
//request.getRequestDispatcher("/result.jsp").forward(request, response);
OutputStream outputStream = response.getOutputStream();
ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
objectOutputStream.writeObject("Success !");
objectOutputStream.flush();
objectOutputStream.close();
}
private String fileToUpload(HttpServletRequest request) throws IOException,
ClassNotFoundException {
ServletInputStream servletIn = request.getInputStream();
ObjectInputStream in = new ObjectInputStream(servletIn);
String uploadFile = (String) in.readObject();
System.out.println("Value in uploadFolder is: " + uploadFile);
return uploadFile;
}
Below is the fileupload applet:
public class FileUpload extends Applet {
private JButton capture;
private JTextField textField;
private final String pathDirectory = "C:\\";
private final String captureConfirmMessage = "Are you sure you want to continue?";
private final String confirmDialogTitle = "Confirm upload";
final File folder = new File(pathDirectory);
public void init() {
upload= new JButton("Upload");
textField = new JTextField();
capture.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
int selection = JOptionPane.showConfirmDialog(upload,
uploadConfirmMessage, confirmDialogTitle,
JOptionPane.YES_NO_OPTION);
if (selection == JOptionPane.OK_OPTION) {
listFilesForFolder(folder);
} else if (selection == JOptionPane.CANCEL_OPTION) {
JOptionPane.showMessageDialog(upload,
"You have aborted upload", "Upload Cancelled", 2);
}
}
});
add(upload);
add(textField);
}
public void listFilesForFolder(final File folder) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
listFilesForFolder(fileEntry);
} else {
try {
onSendData(fileEntry.getAbsolutePath());
System.out.println(fileEntry.getAbsolutePath());
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
private URLConnection getServletConnection() throws MalformedURLException,
IOException {
// Open the servlet connection
URL urlServlet = new URL("http://localhost:8081/UploadFile/upload");
HttpURLConnection servletConnection = (HttpURLConnection) urlServlet
.openConnection();
// Config
servletConnection.setDoInput(true);
servletConnection.setDoOutput(true);
servletConnection.setUseCaches(false);
servletConnection.setDefaultUseCaches(false);
servletConnection.setRequestProperty("Content-Type", "multipart/form-data;");
servletConnection.connect();
return servletConnection;
}
private void onSendData(String fileEntry) {
try {
// Send data to the servlet
HttpURLConnection servletConnection = (HttpURLConnection) getServletConnection();
OutputStream outstream = servletConnection.getOutputStream();
ObjectOutputStream objectOutputStream= new ObjectOutputStream(
outstream);
objectOutputStream.writeObject(fileEntry);
// Receive result from servlet
InputStream inputStream = servletconnection.getInputStream();
ObjectInputStream objectInputStream = new ObjectInputStream(
inputStream);
String result = (String) objectInputStream.readObject();
objectInputStream.close();
inputStream.close();
out.flush();
out.close();
// Display result on the applet
textField.setText(result);
} catch (java.net.MalformedURLException mue) {
mue.printStackTrace();
textField.setText("Invalid serlvetUrl, error: " + mue.getMessage());
} catch (java.io.IOException ioe) {
ioe.printStackTrace();
textField.setText("Couldn't open a URLConnection, error: "
+ ioe.getMessage());
} catch (Exception e) {
e.printStackTrace();
textField.setText("Exception caught, error: " + e.getMessage());
}
}
public void paint(Graphics g) {
g.drawString("Click the button above to capture", 5, 50);
}
I could finally succeed posting the request to the servlet from the applet.
It was a simple logic that I was missing. I did not add the header and trailer while posting to the servlet, which was the key, in the servlet to identify the incoming request as a multipart data.
FileInputStream fileInputStream = new FileInputStream(new File(
fileEntry));
dataOutputStream.writeBytes(twoHyphens + boundary + lineEnd);
dataOutputStream
.writeBytes("Content-Disposition: form-data; name=\"upload\";"
+ " filename=\"" + fileEntry + "\"" + lineEnd);
dataOutputStream.writeBytes(lineEnd);
// create a buffer of maximum size
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
buffer = new byte[bufferSize];
// read file and write it into form
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
dataOutputStream.write(buffer, 0, bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
System.out.println(fileEntry + " uploaded.");
}
// send multipart form data necesssary after file data
dataOutputStream.writeBytes(lineEnd);
dataOutputStream.writeBytes(twoHyphens + boundary + twoHyphens
+ lineEnd);
I added the header and trailer and also used this to create the URL connection.
private URLConnection getServletConnection() throws MalformedURLException,
IOException {
// Open the servlet connection
URL urlServlet = new URL("http://localhost:8083/UploadFile/upload");
HttpURLConnection servletConnection = (HttpURLConnection) urlServlet
.openConnection();
// Config
servletConnection.setDoInput(true);
servletConnection.setDoOutput(true);
servletConnection.setUseCaches(false);
servletConnection.setDefaultUseCaches(false);
servletConnection.setRequestMethod("POST");
servletConnection.setRequestProperty("Content-Type",
"multipart/form-data;boundary=" + this.boundary);
servletConnection.setRequestProperty("Connection", "Keep-Alive");
servletConnection.connect();
return servletConnection;
}
Then, in the servlet, I was just reading the data using upload.ParseRequest(request).
Thank you for the help.
I am working on a web application using jsp and servlet using oracle.jdbc.OracleDriver.This code,working fine on my PC,but when trying to deploy build of application on other server,i am getting Exception like this.
java.sql.SQLException: Missing defines
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:158)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:206)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:305)
at oracle.jdbc.driver.OracleStatement.prepareAccessors(OracleStatement.java:793)
at oracle.jdbc.driver.T4CResultSetAccessor.getCursor(T4CResultSetAccessor.java:235)
at oracle.jdbc.driver.ResultSetAccessor.getObject(ResultSetAccessor.java:95)
at oracle.jdbc.driver.OracleCallableStatement.getObject(OracleCallableStatement.java:1947)
at org.apache.tomcat.dbcp.dbcp.DelegatingCallableStatement.getObject(DelegatingCallableStatement.java:143)
at cwep.Login.processRequest(Login.java:127)
at cwep.Login.doPost(Login.java:198)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:263)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:852)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:584)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1508)
at java.lang.Thread.run(Unknown Source)
After debugging my application,i found that when I am calling database(Oracle 10g) procedure on server side and getting cursor using callableStatement.registerOutParameter(1,OracleTypes.CURSOR), I am getting above Exception at
callableStatement.execute(); statement.
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
static String CNPOOL = "cnpool";//Getting CNPOOL correctly for database connection
CallableStatement cs = null;
static DataSource dataSource;//Declared as global
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
CallableStatement cs = null;
String str = conectionPool;
System.out.println(str);
try {
InitialContext initContext = new InitialContext();
Context context = (Context) initContext.lookup("java:/comp/env");
dataSource = (DataSource) context.lookup(str);
System.out.println(" CxN Pool " + str);
String username = request.getParameter("username");
String password = request.getParameter("password");
ecode = Integer.parseInt(username);
System.out.println(" eCode " + ecode);
try {
con = ConnectionBean.getConnection(dataSource);
System.out.println(" CxN " + con.toString());
} catch (Exception e) {
System.out.println(" Opening the Cxn 1st Time" + e);
}
if(con!=null)
{
System.out.println(" Before Calling proc_user_login " + ecode);
cs = con.prepareCall("{call proc_user_login(?,?,?,?,?)}");
cs.setInt(1, empcode);
cs.setString(2, password);
cs.registerOutParameter(3, Types.NUMERIC);
cs.registerOutParameter(4, Types.NUMERIC);
cs.registerOutParameter(5, Types.VARCHAR);
try {
cs.execute();
} catch (Exception e) {
System.out.println("--------------------After executing first proc----------------------- ");
}
int message = cs.getInt(3);
if (message == 0) {
cs = con.prepareCall("{call proc_get_XXXlist(?,?)}");
cs.setInt(1, empcode);
cs.registerOutParameter(2, OracleTypes.CURSOR);
try {
System.out.println("Before executing XXXList proc ");
cs.execute(); //GETTING EXCEPTION AT THIS STATEMENT
System.out.println("After executing XXXList");
} catch (Exception e) {
System.out.println("exception in After executing secod proc ");
}
ResultSet rset = (ResultSet) cs.getObject(2);
Vector v1 = new Vector();
Vector v2 = new Vector();
Vector v3 = new Vector();
while (rset.next()) {
v1.addElement(rset.getString(1));
v2.addElement(rset.getString(2));
v3.addElement(rset.getString(3));
}
//rset.last();
String[] str1 = new String[v1.size()];
String[] str2 = new String[v2.size()];
String[] str3 = new String[v3.size()];
v1.copyInto(str1);
v2.copyInto(str2);
v3.copyInto(str3);
request.setAttribute("ecode", Integer.toString(ecode));
request.setAttribute("clientid", str1);
request.setAttribute("constring", str2);
request.setAttribute("URL", str3);
RequestDispatcher rd = request.getRequestDispatcher("XXX.jsp");
rd.forward(request, response);
//response.sendRedirect("XXX.jsp");
} else {
response.sendRedirect("index.jsp?val=" + message);
}
}
} catch (Exception e) {
e.printStackTrace();
System.out.println("EEE---" + e);
Utility.log("FinalExceptionToServlet.namelookup:", e.toString(), "SERVER", "E");
}
}
In this code,First database login_usr procedure execute properly,but when trying to execute 2nd procedure,which returns a cursor as outparameter,i'm getting above exception.If same code working fine on my PC,then why it throws exception when trying to execute callablestatement after Serverside deployment.Here I'm using Ojdbc14.jar and classes12.jar.Is there is any .jar missmatch..???
Thanks in advance.
As you have mentioned that the code was running earlier, Here the culprit could be OracleTypes. As its abstract class you need correct and concrete implementation of it which is your Driver.
Verify the version of the JDBC driver and the type of JDBC driver (Thin or OCI) you
Download new jar from oracle site or from here.
Also, try using oracle.jdbc.OracleTypes before looking for drivers.
e.g. cn.registerOutParameter(2, oracle.jdbc.OracleTypes.CURSOR);
I've a servlet that checks username and password from database.
#Override
protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mvs_user", "root", "pass");
if (req.getParameter("usrnm") != null && req.getParameter("pwd") != null) {
String username = req.getParameter("usrnm");
String userpass = req.getParameter("pwd");
String strQuery = "select * from user where username='" + username + "' and password='" + userpass + "'";
System.out.println(strQuery);
Statement st = conn.createStatement();
ResultSet rs = st.executeQuery(strQuery);
if (rs.next()) {
req.getSession(true).setAttribute("username", rs.getString(2));
res.sendRedirect("adminHome.jsp");
} else {
res.sendRedirect("index.jsp");
}
} else {
res.sendRedirect("login.jsp");
}
conn.close();
} catch (Exception e) {
e.printStackTrace();
}
}
The problem is the browser only displays a blank page and yet I expect it to display "Hello World" in the redirected page. Where could the problem be? Please help me troubleshoot.
You need to properly handle exceptions. You should not only print them but really throw them.
Replace
} catch (Exception e) {
e.printStackTrace(); // Or System.out.println(e);
}
by
} catch (Exception e) {
throw new ServletException("Login failed", e);
}
With this change, you will now get a normal error page with a complete stacktrace about the cause of the problem. You can of course also just dig in the server logs to find the stacktrace which you just printed instead of rethrowed.
There are several possible causes of your problem. Maybe a ClassNotFoundException or a SQLException. All which should be self-explaining and googlable.
See also:
How should I connect to JDBC database / datasource in a servlet based application?
How to install JDBC driver in Eclipse web project without facing java.lang.ClassNotFoundexception
The infamous java.sql.SQLException: No suitable driver found
Unrelated to the concrete problem, your JDBC code is prone to resource leaking and SQL injection attacks. Do a research on that as well and fix accordingly.