servlet Query String - java

I am using query string for sending parameter to other page in form action tag
but when I am fetching the value on the next page, it is showing null and null is stored in the database.
My code is as follows:
out.println("<html>");
out.println("<form action=SubmitTimesheet?manager="+manager+">");
and on the other page I am trying to fetch the value of parameter in following manner:
String manager=request.getParameter("manager");
out.println(manager);
But it is printing null and further if I am trying to store the fetched value in database it is storing null.
Please help.

i have use session object and passed the value of manager in session variable instead of query string.
i have used the following code:
ses.putValue("manager", manager);
on the first servlet page and then on the second servlet page i fetched the value like this :
String manager=ses.getValue("manager").toString();
out.println(manager);
now it is printing the correct value instead of null

Don't add the manager query parameter if the manager value is null.
Also remember to encode query parameters.
And finally, the value of the action attribute should be quoted.
out.print("<form action=\"SubmitTimesheet");
if (manager != null)
out.print("?manager=" + URLEncoder.encode(manager, "UTF-8"));
out.println("\">");
Instead of the "UTF-8" string literal, you can also use StandardCharsets.UTF_8.
UPDATE
In reality, you shouldn't add query parameters to the action of a <form>. The form will post all the values of <input> and other form related elements, so what you should do, is add the manager value as a hidden input field:
out.println("<html>");
out.println("<form action=\"SubmitTimesheet\">");
if (manager != null)
out.print("<input name=\"manager\" type=\"hidden\" value=\"" +
StringEscapeUtils.escapeHtml4(manager) + "\">");
The above uses the library suggested by answer to question Recommended method for escaping HTML in Java.

Related

How to retrieve an integer URL parameter with JSP? [duplicate]

In JSP how do I get parameters from the URL?
For example I have a URL www.somesite.com/Transaction_List.jsp?accountID=5
I want to get the 5.
Is there a request.getAttribute( "accountID" ) like there is for sessions or something similar?
About the Implicit Objects of the Unified Expression Language, the Java EE 5 Tutorial writes:
Implicit Objects
The JSP expression language defines a set of implicit objects:
pageContext: The context for the JSP page. Provides access to various objects including:
servletContext: The context for the JSP page’s servlet and any web components contained in the same application. See Accessing the Web Context.
session: The session object for the client. See Maintaining Client State.
request: The request triggering the execution of the JSP page. See Getting Information from Requests.
response: The response returned by the JSP page. See Constructing Responses.
In addition, several implicit objects are available that allow easy access to the following objects:
param: Maps a request parameter name to a single value
paramValues: Maps a request parameter name to an array of values
header: Maps a request header name to a single value
headerValues: Maps a request header name to an array of values
cookie: Maps a cookie name to a single cookie
initParam: Maps a context initialization parameter name to a single value
Finally, there are objects that allow access to the various scoped variables described in Using Scope Objects.
pageScope: Maps page-scoped variable names to their values
requestScope: Maps request-scoped variable names to their values
sessionScope: Maps session-scoped variable names to their values
applicationScope: Maps application-scoped variable names to their values
The interesting parts are in bold :)
So, to answer your question, you should be able to access it like this (using EL):
${param.accountID}
Or, using JSP Scriptlets (not recommended):
<%
String accountId = request.getParameter("accountID");
%>
In a GET request, the request parameters are taken from the query string (the data following the question mark on the URL). For example, the URL http://hostname.com?p1=v1&p2=v2 contains two request parameters - - p1 and p2. In a POST request, the request parameters are taken from both query string and the posted data which is encoded in the body of the request.
This example demonstrates how to include the value of a request parameter in the generated output:
Hello <b><%= request.getParameter("name") %></b>!
If the page was accessed with the URL:
http://hostname.com/mywebapp/mypage.jsp?name=John+Smith
the resulting output would be:
Hello <b>John Smith</b>!
If name is not specified on the query string, the output would be:
Hello <b>null</b>!
This example uses the value of a query parameter in a scriptlet:
<%
if (request.getParameter("name") == null) {
out.println("Please enter your name.");
} else {
out.println("Hello <b>"+request. getParameter("name")+"</b>!");
}
%>
Use EL (JSP Expression Language):
${param.accountID}
If I may add a comment here...
<c:out value="${param.accountID}"></c:out>
doesn't work for me (it prints a 0).
Instead, this works:
<c:out value="${param['accountID']}"></c:out>
request.getParameter("accountID") is what you're looking for. This is part of the Java Servlet API. See http://java.sun.com/j2ee/sdk_1.3/techdocs/api/javax/servlet/ServletRequest.html for more information.
String accountID = request.getParameter("accountID");
www.somesite.com/Transaction_List.jsp?accountID=5
For this URL there is a method call request.getParameter in java , if you want a number here cast into int, similarly for string value cast into string. so for your requirement , just copy past below line in page,
int accountId =(int)request.getParameter("accountID");
you can now call this value useing accountId in whole page.
here accountId is name of parameter you can also get more than one parameters using this, but this not work. It will only work with GET method if you hit POST request then their will be an error.
Hope this is helpful.
example you wanted to delete the subject record with its subject_id
#RequestMapping(value="subject_setup/delete/{subjectid}",method = RequestMethod.GET)
public ModelAndView delete(#PathVariable int subjectid) {
subjectsDao.delete(subjectid);
return new ModelAndView("redirect:/subject_setup");
}
and the parameter will be used for input on your query
public int delete(int subjectid) {
String sql = "update tbl_subject set isdeleted= '1' where id = "+subjectid+"";
return template.update(sql);
}
page 1 :
Detail
page 2 :
<% String id = request.getParameter("userid");%>
// now you can using id for sql query of hsql detail product

how to pass value to VO which is inside map and VO

I have CompanyProfileVO in which I have declared companyProfile_addressVOMap as map of String and VO
i want to give value to the company_name which is present in side AddressIdentificationVO in the form of url encoded
How can I set value of company_name through url encoded form?
To get the value I'm using this
CompanyProfileVO.getCompanyProfile_addressVOMap().get("COMPANY").getCompany_name()
CompanyProfileVO.java
Map<String,AddressIdentificationVO> companyProfile_addressVOMap;
AddressIdentificationVO
#FormParam("company_name")
String company_name;
According to your Code you need to create two different Variable object 1 for json and 1 for XMl(URL encoded). you should pass your
Map<String,AddressIdentificationVO> companyProfile_addressVOMap;
AddressIdentificationVO inside JSONVO and call the JSON method When u hit the URL Encoded method .

Servlets and html issue

I am attempting to learn how to use a querystring. My goal is to modify a servlet and from that be able to pull data from a querystring in my URL. I specifically need to show the "action". My URL querystring is to be entered as
?param1=val1&param2=val2. I attempted to modify my servlets processRequest with the following line:
out.println("<p>" + request.getParameter("<p> Action is" [value] "</p>") +</p>);
Any ideas of where to go from here? I'm getting several errors.
You are retrieving invalid values from the request parameters.
More specifically, based on your querystring you should retrieve the parameters param1 and param2, which will contain values val1 and val2 respectively, like so:
String p1 = request.getParameter("param1");
String p2 = request.getParameter("param2");
System.out.println("params: 1:"+p1+" 2:"+p2);

How to change url in address bar through java

How can I change the url in the address bar through java code in browser(not through javascript or any front end languages)?
I have the url in the address bar like " http://www.abcde.com/home?abc=def&ghi=jkl " but I need to change that url through java code like " http://www.abcde.com/home ". I'm using jsp's for view.
Can anyone help?
If the URL with the request parameters comes from a page on which you have no control (or if it is a link) you can do the following :
use a servlet on that URL
if it finds request parameters in the query strings, it gets them and store them in session, then redirects to itself with no query string
if there is no query string, get the parameter from session, remove them from the session to avoid to reuse them by mistake and process the query
If the parameters exists in query string, because of a form using GET method, simply change the method to POST to pass the parameters in the request body instead of the query string.

Java Servlet Appending to StringBuffer Unrecognized HTML code

How do I give data from one servlet to the next?
Anything after ? is part of the query string. In a Servlet, each key value pair in the query string becomes a request parameters.
If you have access to the HttpServletRequest, you can access them with HttpServletRequest#getParameter(String). For example
request.getParameter("myId");

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