Develop Reference

Getting image/video from html into java servlet as new File()

I want to get a file (image or video) from an
<input type='file' id='file_i'/>
// Not this <input type='submit'/>
Using an XMLHttpRequest like this
function img() {
var fd = new FormData();
fd.append('file', document.getElementById("file_i").files[0]);
var req;
if (window.ActiveXObject) {
req=new ActiveXObject();
} else {
req=new XMLHttpRequest();
}
req.open("post", "Image", true);
req.send(fd);
}
for example.
Then in the servlet doing this:
new FileInputStream(new File(request.getParameter("file")))
How can I retrieve that file?
Thanks in advance.

I fixed it. Here it is:
JAVASCRIPT
var fd = new FormData();
fd.append('file', document.getElementById("file_i").files[0]);
var req;
if (window.ActiveXObject) {
req=new ActiveXObject();
} else {
req=new XMLHttpRequest();
}
req.open("post", "Image", true);
req.send(fd);
JAVA
#MultipartConfig
public class addImage extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
Part filePart = request.getPart("file");
InputStream fileContent = filePart.getInputStream();
}
}
XML
<servlet>
<servlet-name>Add Image</servlet-name>
<servlet-class>servlets.addImage</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Add Image</servlet-name>
<url-pattern>/Image</url-pattern>
</servlet-mapping>

I think you miss some points.
It seems in your JavaScript code, that you just create the request. But you didn't respond to results.
req.addEventListener("load", reqListener);
You should define reqListener like that:
function reqListener () {
// Here try to handle the response text, using "this.responseText"
console.log(this.responseText);
}
See the full info here:
Using XMLHttpRequest
Also in your Java code, you just stated that you created a file stream.
You should read from this input stream into the request's output stream. Also you should set the header Content-Type: put_your_mime_type_here, For example: Content-Type: application/json, if your file is a json file, Content-Type: image/png, if your file is a PNG image.
See an example here: Example for making a file download URL in Java

AJAX call to struts action not working

Hi i have a requirement in which i have to check something from struts action class and then send the result back to the browser using ajax call called in a JS fx'.The issue is im not able to hit the action class and console is throwing the following error:
org.apache.struts.action.RequestProcessor processActionCreate No action instance for path /ChangePwdAjax could be created
java.lang.ClassNotFoundException:test.ChangePwdAjaxAction.java
The class is compiled and the package context is valid test.ChangePwdAjaxAction.java
Any ideas what and where im doing it wrong?
Here is what i have written so far.
JS code
function checkError()
{
var valuePassword="test";
var url = "/test/ChangePwdAjax.do?newPass="+valuePassword;
var xmlHTTP = getXMLHTTPRequest();
xmlHTTP.onreadystatechange = function() {
handleResponse(xmlHTTP); }
xmlHTTP.open("GET",url,true);
xmlHTTP.send();
}
function handleResponse(xmlHTTP){
alert("handleResponse");
if (xmlHTTP.readyState == 4 && xmlHTTP.status == 200) {
alert("handleResponse");
var xmlDoc = xmlHTTP.responseXML;
alert(xmlDoc.documentElement.getElementsByTagName("pwdFlag")[0].text);
}
}
function getXMLHTTPRequest(){
alert("getXMLHTTPRequest");
if (window.XMLHttpRequest) {
return new XMLHttpRequest();
}
// IE
else if (window.ActiveXObject) {
return new ActiveXObject("Microsoft.XMLHTTP");
}
else{
alert("XMLHttpRequest is not supported!");
}
}
Action class code
public class ChangePwdAjaxAction extends Action {
public ActionForward execute(final ActionMapping mapping, final ActionForm form,
final HttpServletRequest request,final HttpServletResponse response)
{
System.out.println("----IN--AJAX ACTION----------");
final HttpSession session= request.getSession(false);
if(session==null || session.getAttribute("user_id")==null){
return mapping.findForward("sessionexpired");
}
final String user_id=(String)session.getAttribute("user_id");
try{
final BusinessDelegate busdel=new BusinessDelegate(user_id,session.getId());
String newpwd = (String)request.getParameter("newPass");
boolean b=busdel.checkOldPWd(user_id, newpwd);
//checking return values from bus delegate
response.setContentType("text/xml");
PrintWriter printwriter = response.getWriter();
printwriter.println("<?xml version=\"1.0\"?>");
printwriter.println("<Root>");
if(b)
{
System.err.println("----New password Failed--Y--------");
printwriter.println("<pwdFlag>"+"Y"+"</pwdFlag>");
}
else
{
System.out.println("----New password OK---N-------");
printwriter.println("<pwdFlag>"+"N"+"</pwdFlag>");
}
printwriter.println("</Root>");
}catch(Exception e){
logger.logCommon("Login Action : Login Process in Action : ", "EXCEPTION");
logger.logError(e);
}
return null;
}
}
Struts-config entry
<action path="/ChangePwdAjax" type="test.ChangePwdAjaxAction.java"/>

OOps this had to be
action path="/ChangePwdAjax" type="test.ChangePwdAjaxAction"/>
rather than
action path="/ChangePwdAjax" type="test.ChangePwdAjaxAction.java"/>

How get the data using MVC- Servlets, JPS and JavaScripts

I have JSP page that has links (When people click on the link it is supposed to go to a servlet and then Bean class and DB Connection class to pull the data)..and when a user clicks on the like I tried to display the page using AJAX...however i am currently not getting any data/page pulled. Can someone please explain on how to achive this?
here is the link i have in my HTML page..but when i click on it is not showing up anything.
VT
Thanks for your help
Sorry here is my code
public class VacationTrackerDAO {
public static List<VactionTrackerBean> list() throws SQLException{
List<VactionTrackerBean> appr= new ArrayList<VactionTrackerBean>();
try{
DBConnection conObj=new DBConnection();
Connection dbCon= conObj.getCon();
Statement stmt=conObj.getStmt();
String queryCPList="select * from Capacity_Plan";
String queryApprList="Select First_Last_Name from Vacation_Approvers";
PreparedStatement preStmtCPList=dbCon.prepareStatement(queryCPList);//get metadat
PreparedStatement preStmtApprList=dbCon.prepareStatement(queryApprList);//get names
ResultSet rsCPList=preStmtCPList.executeQuery();
ResultSet rsApprList=preStmtCPList.executeQuery();
ResultSetMetaData metaCPList=rsCPList.getMetaData();
VactionTrackerBean vtBean=new VactionTrackerBean();
while(rsApprList.next()){
vtBean.setApprover((rsApprList.getString("First_Last_Name")));
appr.add(vtBean);
}
}catch(Exception e){
System.out.println("In the Vacation TrackerDAO.java class:"+e);
}
return appr;
}
}
Here is my Servlets which gets the request.
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try{
List<VactionTrackerBean> vacBean=VacationTrackerDAO.list();
request.setAttribute("vacTracker", vacBean);
request.getRequestDispatcher("WEB-INF/VacationTracker.jsp").forward(request,response);
}catch (SQLException e){
System.out.println("Error in VacationTracker.java due to VactionTrackerDA.java:"+e);
request.getRequestDispatcher("WEB-INF/Error.jsp").forward(request,response);
}
Here is the code that i have in the JSP page.
<li> <a href="Main.jsp" > home </a> </li>
<li>Vacation Tracker </li>
</ul>
Here is the code for my Javascript
function getHTTPObject(){
var xhr=false;
if(window.XMLHttpRequest){
xhr= new XMLHttpRequest();
} else if(window.ActiveXObject){
try{
xhr= new ActiveXObject("Msxml2.XMLHTTP");
} catch(e){
try{
xhr=new ActiveXObject("Microsoft.XMLHTTP");
}catch (e){
xhr=false;
}
}
}
return xhr;
}
function grabfile(file){
var request=getHTTPObject();
if(request){
request.onreadystatechange=function(){ displayResponse(request);};
}
request.open("POST",file,true);
request.send(null);
}
function displayResponse(request){
if(request.readyState==4){
if(request.status==200){
document.getElementById ("middle_sub").innerHTML=request.responseText;
}
}
}

onclick insert in to ms sql database

I have asp.net application with JavaScript and I want to save in to ms sql DB additional information(TimeStamp) when a button is clicked.
onclick= "functionName();"
the function "functionName()" has another task and I want another function that store the timestamp as well

Write JS as below:
function functionName() {
var xmlhttp;
if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
}
else {// code for IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
alert(xmlhttp.responseText);
}
}
var now = new Date(); // You can also any kind of data using query string
xmlhttp.open("GET", "saveTimespan.aspx?datetime=" + now, true);
xmlhttp.send();
}
Write below code to code behind of saveTimespan.aspx' page as below(remove all markup other thanPage` directory of this page):
protected void Page_Load(object sender, EventArgs e)
{
UpdateTimeStamp();
}
public void UpdateTimeStamp()
{
SqlCommand cmd = new SqlCommand();
cmd.CommandText = "UPDATE TargetTable SET DateTimColumnName = #DateTimColumnName";
cmd.Parameters.AddWithValue("#DateTimColumnName", MyDateTime);
cmd.CommandType = CommandType.Text;
try
{
using (SqlConnection connection = new SqlConnection("YourConnectionString"))
{
cmd.Connection = connection;
connection.Open();
cmd.ExecuteNonQuery();
Response.Write("Data Updated Successfully!");
}
}
catch (Exception ex)
{
//Handle exception
}
}

Try using jQuery ajax, would be easier like
function functionName() {
$.ajax({
url: "test.html",
context: document.body,
success: function(){
$(this).addClass("done");
}
});
}
Ref: http://api.jquery.com/jQuery.ajax/

not receiving data from http inputstream

function sendRequestToDelicious()
{
var xmlhttp=false;
if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
try {
xmlhttp = new XMLHttpRequest();
} catch (e) {
xmlhttp=false;
}
}
if (!xmlhttp && window.createRequest) {
try {
xmlhttp = window.createRequest();
} catch (e) {
xmlhttp=false;
}
}
var url = "http://localhost:52271/WebForm1.aspx";
var params = "q=hello";
xmlhttp.open("POST", url, true);
//Send the proper header information along with the request
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.setRequestHeader("Content-length", params.length);
xmlhttp.send(params);
}
In my ASP.NET app, I am reading the stream from page_load event, but I'm not receiving the data. what am I doing wrong?
C# CODE IN ASP.NET:
public partial class WebForm1 : System.Web.UI.Page
{
SqlConnection conn;
protected void Page_Load(object sender, EventArgs e)
{
StreamReader reader = new StreamReader(Page.Request.InputStream);
String data = reader.ReadToEnd();
}
...

It looks like this post contains the precise code for what you are trying to do:
Fake a form submission with C# WebClient
If you just need the data at Page_Load there isn't a requirement to do this with JavaScript- right?
I personally don't use the XmlHttpRequest object any more. I have abandoned it in favor of using the jQuery AJAX functions. The callback function for a successful post would make it easy to capture the response from the server.
Here is an example of how to do it with jQuery AJAX:
$.ajax(
{
type : 'POST',
url : 'http://localhost:52271/WebForm1.aspx',
dataType : 'json',
data:
{
q:'hello'
},
success : function(data)
{
$('mydiv').text(data.msg).show(500);
},
error : function(XMLHttpRequest, textStatus, errorThrown)
{
$('mydiv').text('There was an error.').show(500);
}
}
);