Java.lang.NumberFormatException: for input line in JSP page

Question

Hi, someone can help why this gives an error when trying to display values ​​on a JSP page. I don't have a number that was converted or String was converted to Number, however I get a NumberFormatException

my servlet receives a request to display the user record

if(action.equalsIgnoreCase("update")){ System.out.println("Came into Update"); userId=(int) Integer.parseInt(request.getParameter("userid")); nbId=request.getParameter("nbId").trim(); System.out.println("User iD and NBid: "+ userId + nbId); User user=new User(); user.setUser_id(userId); user.setUser_nbk(nbId); List userRecords=UserDAO.getUserRecord(user); request.setAttribute("userRecords", userRecords); List owningOrg=Owning_Org_DB.getOwningOrgRecords(); request.setAttribute("owningOrg", owningOrg); request.getRequestDispatcher("WEB-INF/JSP/TableMaintenance/UserNewAdd.jsp").forward(request, response); 

POJO:

  @Entity @Cache(usage=CacheConcurrencyStrategy.READ_WRITE) public class User { @Id private int user_id; private String user_first_name; private String user_middle_name; private String user_last_name; //getters and setters methos } 

DAO:

 public static List getUserRecord(User obj){ Logger lo=LoggerFactory.getLogger("UserDAO.getUserRecord"); Session session= Annotationsessionfactory.getAnnotationSession(); Transaction tx=session.beginTransaction(); lo.debug("Request for A user Record"); //List<User> recList=new ArrayList<User>(); List recList=null; try{ //String userRecord="from User"; Criteria userList=session.createCriteria(User.class) .add(Restrictions.eq("user_nbk", obj.getUser_nbk())) .add(Restrictions.eq("user_id", obj.getUser_id())); recList=userList.list(); System.out.println(recList.size()); }catch (Exception e){ lo.info("Exception Occured in UserDAO.getUserRecord"); lo.debug("Exception Occured in UserDAO.getUserRecord:"+e); tx.rollback(); }finally{ session.close(); lo.info("Session Closed in UserDAO.userRecordslist finally block: "); } lo.debug("Record was sent to the requesting servlet or method: "+ recList); return recList; } 

JSP Page

 <table> <tr> <td>First Name</td> <td><input type="text" id="firstname" name="firstname" maxlength="80" value="">${userRecords.user_first_name}</td> </tr> <tr> <td>Middle Name</td> <td><input type="text" id="middlename" name="middlename" maxlength="80" value="${userRecords.user_middle_name}"></td> ....... 

An exception:

 SEVERE: Servlet.service() for servlet jsp threw exception **java.lang.NumberFormatException: For input string: "user_first_name"** at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48) at java.lang.Integer.parseInt(Integer.java:447) at java.lang.Integer.parseInt(Integer.java:497) at javax.el.ListELResolver.coerce(ListELResolver.java:166) at javax.el.ListELResolver.getValue(ListELResolver.java:51) at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54) at org.apache.el.parser.AstValue.getValue(AstValue.java:123) at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:938) at org.apache.jsp.WEB_002dINF.JSP.TableMaintenance.UserNewAdd_jsp._jspService (UserNewAdd_jsp.java:77) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 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.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302) at com.servicedbUpdate.UserUpdateDB_NewAdds.doPost(UserUpdateDB_NewAdds.java:79) at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 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:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:879) at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:600) at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1703) at java.lang.Thread.run(Thread.java:619) Feb 13, 2013 10:30:49 AM org.apache.catalina.core.StandardWrapperValve invoke SEVERE: Servlet.service() for servlet UserUpdateDB_NewAdds threw exception **java.lang.NumberFormatException: For input string: "user_first_name"** at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48) at java.lang.Integer.parseInt(Integer.java:447) at java.lang.Integer.parseInt(Integer.java:497) at javax.el.ListELResolver.coerce(ListELResolver.java:166) at javax.el.ListELResolver.getValue(ListELResolver.java:51) at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54) at org.apache.el.parser.AstValue.getValue(AstValue.java:123) at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:938) at org.apache.jsp.WEB_002dINF.JSP.TableMaintenance.UserNewAdd_jsp._jspService(UserNewAdd_jsp.java:77) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 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.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302) at com.servicedbUpdate.UserUpdateDB_NewAdds.doPost(UserUpdateDB_NewAdds.java:79) at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 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:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:879) at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:600) at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1703) at java.lang.Thread.run(Thread.java:619) 

Answer 1

${userRecords} here

 ${userRecords.user_first_name} ${userRecords.user_middle_name} 

is a List<User> , however you are trying to access it as if it were a single User . This is not true. In EL, a List can only be accessed with an integer index, indicating the position of the list item you want to access, for example

 ${userRecords[0].user_first_name} ${userRecords[0].user_middle_name} 

The exception also basically says that it expects an integer value instead of a string value. If you look closer at the stack trace, you will see that ListELResolver is being used.

However your specific problem is bigger. You have to really iterate over the list. To do this, use JSTL <c:forEach> . For instance. (simplified from an odd code fragment):

 <table> <c:forEach items="${userRecords}" var="user"> <tr> <td>${user.user_first_name}</td> <td>${user.user_middle_name}</td> </tr> </c:forEach> </table> 

(note: keep the XSS attack hole in mind if you really intend to re-map them as input values)

By the way, I would work on Java code conventions . These underscores are not really Java ishes.