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PONullpointer exception while transfering a value from jsp to servlet
 

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  1. PONullpointer exception while transfering a value from jsp to servlet
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    <p>my project concept is depend upon the dropdown value the control will be tranfer to the related jsp page.</p> <p>i created 4 dropdown value</p> <p>1.andriod</p> <p>2.struts</p> <p>3.spring</p> <p>4.hibernate</p> <p>And 4 jsp page</p> <p>1.andriod.jsp</p> <p>2.struts.jsp</p> <p>3.spring.jsp</p> <p>4.hibernate.jsp</p> <p>if i selected andriod and click the submit button mean the control will be transfer to andriod.jsp page,similarly other value also transfered,</p> <p>My Problem is </p> <p>If i selected andriod and click the submit button it always shows null pointer exception...</p> <p>Please any one solve my problem.</p> <p>i created</p> <p>1.jsp page(Filename.jsp)</p> <p>2.Servlet page(CatServ.java)</p> <p><strong>NewFile.jsp</strong></p> <pre><code>&lt;body&gt; &lt;form action="test" method="post"&gt; &lt;table&gt; &lt;tr&gt; &lt;td&gt; Select the category&lt;/td&gt; &lt;td&gt; &lt;select&gt; &lt;option name="andriod" value="lang"&gt;Andriod&lt;/option&gt; &lt;option name="java" value="lang"&gt;Java&lt;/option&gt; &lt;option name="struts" value="lang"&gt;Struts&lt;/option&gt; &lt;option name="spring" value="lang"&gt;Spring&lt;/option&gt; &lt;option name="hybernate" value="lang"&gt;Hybernate&lt;/option&gt; &lt;/select&gt; &lt;/td&gt; &lt;/tr&gt; &lt;tr&gt; &lt;td&gt;&lt;center&gt; &lt;input type="submit" value="Submit"&gt;&lt;/center&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; &lt;/form&gt; &lt;/body&gt; </code></pre> <p><strong>CatServ.java</strong></p> <pre><code>package container; import java.io.IOException; import javax.servlet.RequestDispatcher; 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 CatServ */ @WebServlet("/CatServ") public class CatServ extends HttpServlet { private static final long serialVersionUID = 1L; protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub String s=request.getParameter("lang"); System.out.println(s); if(s.equals("andriod")) { RequestDispatcher rd=request.getRequestDispatcher("AndriodServ.jsp"); rd.forward(request, response); } else if(s.equals("java")) { RequestDispatcher rd=request.getRequestDispatcher("JavaServ.jsp"); rd.forward(request, response); } else if(s.equals("struts")) { RequestDispatcher rd=request.getRequestDispatcher("StrutsServ.jsp"); rd.forward(request, response); } else if(s.equals("spring")) { RequestDispatcher rd=request.getRequestDispatcher("SpringServ.jsp"); rd.forward(request, response); } else if(s.equals("hibernate")) { RequestDispatcher rd=request.getRequestDispatcher("Hybernate.jsp"); rd.forward(request, response); } } } </code></pre>
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    1. USRyan Stewart
    1. USGiri
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      1. VTDownMod
    1. COi post my html code but i will be disable,please any one enable my html code,i don't know how to enable it...
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      1. USGiri
    2. COPut your code in code blocks (the button with the curly braces). Also, don't forget to properly format your code, too.
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      1. USMakoto
    3. CORead, then give us the full stack trace of the exception. It tells you exactly at which line in which file the error happens. Errors are not just red flags. They come with meaningful error messages intended to be read by the developer (YOU).
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      1. USJB Nizet
 

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