Difficulty in passing text as parameter from android to jsp page

问题

I am trying to pass a text from the spinner. Actually the spinner contains the textx which I have fetched from the server side of my application. So what I am trying to do is that, as soon as I select text from the spinner, I want that string to be passed to the server side. So here i am passing the text to a function which can make a request to the JSP.

Main part of the code(android)

    categ = ((TextView) selectedItemView).getText().toString(); 
    postData(categ);

//Remaining section
public void postData(categ) 
{

    String page="processing_pages/individual_phone_communicator.jsp?rom="+categ;
    result = ws.getWebData(page);
    if (result != null)
       plotData();
    else
       alerter("null");

}

(It is returning a null value always.But when i am directly running the same query without any parameter and taking the value directly at the JSP page, it shows result)

Now it will move to the JSP.

String hk=request.getParameter("rom");

Now i am running a query like this:

sqlstatem="select first_name,latitude,longitude from tbluserdetails where user_id=(select user_id from tblindividual_job where jcat_id=(select jcat_id from tbljobcat where job_name='"+hk+"'))";

I am expecting it to give back data in the form of json array. But instead it is showing an error. I tried entering the parameter directly from browser even. Sometimes, the page is displaying correct answer with above query. This makes me more confusing. But when i tried with numbers such as 1 or 2 from the eclipse:

String page="processing_pages/individual_phone_communicator.jsp?rom=2"

and modified the query by trying the exact word instead of 'hk' like this

int rom=Integer.parseInt(request.getParameter("romo"));
if(rom==1)
{
   sqlstatem="select first_name,latitude,longitude from tbluserdetails";
}
else
{
sqlstatem="select first_name,latitude,longitude from tbluserdetails where user_id=(select user_id from tblindividual_job where jcat_id=(select jcat_id from tbljobcat where job_name='Blood donar'))";
}

it is running correctly. From browser also, it is running correctly when i pass integer as parameter. But i need it to be running by taking a text from the emulator as parameter.

But when I try, like this:

String page="processing_pages/individual_phone_communicator.jsp?rom=Blood donor"

Then also i am getting null as result. What I assume is that, my JSP page is only taking integer parameters, I don't know why it is happening.

I am using net beans for JSP. Kindly find me a solution for this issue. Kindly ignore if the question is childish, as i am just a beginner.

回答1:

I don't know what the "ws" variable is, but the IP for your local machine (not the phone) in the android emulator is 10.0.2.2. So any URL pointing to a local web app on your machine should start with http://10.0.2.2/...

Mike

来源：https://stackoverflow.com/questions/8174881/difficulty-in-passing-text-as-parameter-from-android-to-jsp-page