I wrote this Code to check and create a cookie.It loops through the array returned by the request object.But it throws exception.It's thrown at the beginning of the for loop.
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class CookieLogin extends HttpServlet {
PrintWriter out;
boolean flag;
public void doPost(HttpServletRequest req,HttpServletResponse res) throws IOException,ServletException{
Cookie[] cookies = req.getCookies();
out = res.getWriter();
for(int i=0;i<cookies.length;i++){
if(cookies[i].getName().equals("session_started")){
flag=true;
out.println("Your session started on "+cookies[i].getValue());
}
}
if(!flag){
String time = new java.util.Date().toString();
res.addCookie(new Cookie("session_started",time));
out.println("just started");
}
}
}
Here's the Stack Trace from eclipse.
java.lang.NullPointerException
at CookieLogin.doPost(CookieLogin.java:11)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
req.getCookies() returned null,so cookies.length throws NullPointerException,
you should check wheather the req.getCookies(); is null;
The NullPointerException is because getCookies() method will return null if there are no cookies. And so it throws a NullPointerException.
Solution:Check for null
for(int i=0;cookies!=null&&i<cookies.length;i++)
Related
String id = request.getParameter("id");
try {
Class.forName("org.postgresql.Driver");
Connection con = DriverManager.getConnection("jdbc:postgresql://172.10.10.3:5432/stepup380qty","stepup380qty","stepup380qty");
String query = "select binarydata from ad_image where ad_image_id =" + id;
Statement stm = con.createStatement();
ResultSet rs = stm.executeQuery(query);
rs.next();
String img = rs.getString("binarydata");
byte[] img2 = new byte[img.length()];
InputStream imgstream = rs.getBinaryStream("binarydata");
int index = imgstream.read(img2, 0, img.length());
stm.close();
response.reset();
response.setContentType("image/jpg");
response.getOutputStream().write(img2,0,img2.length);
response.getOutputStream().flush();
imgstream.close();
}
catch (SQLException e) {
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
}
This is my code and i am getting this error
org.postgresql.util.PSQLException: ResultSet not positioned properly, perhaps you need to call next.
at org.postgresql.jdbc2.AbstractJdbc2ResultSet.checkResultSet(AbstractJdbc2ResultSet.java:2881)
at org.postgresql.jdbc2.AbstractJdbc2ResultSet.getString(AbstractJdbc2ResultSet.java:1956)
at org.postgresql.jdbc2.AbstractJdbc2ResultSet.getString(AbstractJdbc2ResultSet.java:2568)
at ireportImage.IreportIMAGE.doGet(IreportIMAGE.java:48)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
I am developing a little webapp meant to be run on Tomcat. The webapp works fine on my Windows machine (Windows 7, Java 1.8, Tomcat 7) but fails to run on my raspberry pi 3 (Raspian with the lastest update, Java 1.8, Tomcat 7). Starting Tomcat is fine until one try to load the login page. Then I got the following output :
Error when loading localhost:8080/Timbreuse/connection
java.lang.NullPointerException
at ch.cpnv.timbreuse.servlets.Connection.doGet(Connection.java:39)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:748)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:486)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:411)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at ch.cpnv.timbreuse.filters.ConnectedFilter.doFilter(ConnectedFilter.java:39)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
Message : null
java.lang.NullPointerException
at ch.cpnv.timbreuse.servlets.Connection.doGet(Connection.java:39)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:748)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:486)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:411)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at ch.cpnv.timbreuse.filters.ConnectedFilter.doFilter(ConnectedFilter.java:39)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
Connection.java:39
public static final String VIEW_CONNECTION = "/WEB-INF/connection.jsp";
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
this.getServletContext().getRequestDispatcher(VIEW_CONNECTION).forward(request, response);
}
Folder architecture when the .war is deployed on the Pi
./student
./student/info.jsp
./display
./display/welcomeDisplay.jsp
./display/showDisplay.jsp
./WEB-INF
./WEB-INF/header.jsp
./WEB-INF/changePassword.jsp
./WEB-INF/classes
./WEB-INF/classes/ch
./WEB-INF/classes/ch/cpnv
./WEB-INF/classes/ch/cpnv/timbreuse
./WEB-INF/classes/ch/cpnv/timbreuse/automation
./WEB-INF/classes/ch/cpnv/timbreuse/automation/Automation.java
./WEB-INF/classes/ch/cpnv/timbreuse/automation/Automation.class
./WEB-INF/classes/ch/cpnv/timbreuse/automation/EndOfDay$EndOfDayTask.class
./WEB-INF/classes/ch/cpnv/timbreuse/automation/EndOfDay.class
./WEB-INF/classes/ch/cpnv/timbreuse/automation/EndOfDay.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms
./WEB-INF/classes/ch/cpnv/timbreuse/forms/AddTimeStudentsForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/CreateStudentForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/ChangePasssowordForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/CreateStudentForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/StudentResearchForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/AddTimeStudentsForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/CreateAdminForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/DeleteStudentForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/ConnectionForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/DeleteStudentForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/DeleteTeacherForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/ChangePasssowordForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/StudentResearchForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/DeleteAdminForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/CreateTeacherForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/DeleteAdminForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/ConnectionForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/SetHolydaysForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/CreateAdminForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/CreateTeacherForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/forms/SetHolydaysForm.class
./WEB-INF/classes/ch/cpnv/timbreuse/forms/DeleteTeacherForm.java
./WEB-INF/classes/ch/cpnv/timbreuse/beans
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Teacher.class
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Teacher.java
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Student.class
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Student.java
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Log.class
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Log.java
./WEB-INF/classes/ch/cpnv/timbreuse/beans/User.class
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Holyday.java
./WEB-INF/classes/ch/cpnv/timbreuse/beans/Holyday.class
./WEB-INF/classes/ch/cpnv/timbreuse/beans/User.java
./WEB-INF/classes/ch/cpnv/timbreuse/config
./WEB-INF/classes/ch/cpnv/timbreuse/config/DAOFactoryInitialisation.class
./WEB-INF/classes/ch/cpnv/timbreuse/config/DAOFactoryInitialisation.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOUtility.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplUser.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplTeacher.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOUser.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOLog.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOStudent.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOUtility.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOTeacher.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOException.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplStudent.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplTeacher.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplHolyday.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/dao.properties
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplUser.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplHolyday.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOFactory.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplLog.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplAdmin.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplStudent.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOHolyday.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOFactory.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOTeacher.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplAdmin.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOException.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOUser.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOHolyday.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOLog.java
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOStudent.class
./WEB-INF/classes/ch/cpnv/timbreuse/dao/DAOImplLog.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/SetTimetable.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/AdminPanel.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/Display.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/Connection.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/Logout.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/SetTimetable.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/ChangePassword.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/Logout.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/SetHolydays.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/AdminPanel.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/StudentInfo.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/ChangePassword.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/EndDay.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/ManageStudents.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/ManageStudents.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/Display.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/Connection.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/EndDay.java
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/StudentInfo.class
./WEB-INF/classes/ch/cpnv/timbreuse/servlets/SetHolydays.java
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime/Math.class
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime/Math.java
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime/Date.class
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime/SecondsPastMidnight.class
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime/SecondsPastMidnight.java
./WEB-INF/classes/ch/cpnv/timbreuse/mathTime/Date.java
./WEB-INF/classes/ch/cpnv/timbreuse/filters
./WEB-INF/classes/ch/cpnv/timbreuse/filters/ConnectedFilter.class
./WEB-INF/classes/ch/cpnv/timbreuse/filters/ConnectionFilter.class
./WEB-INF/classes/ch/cpnv/timbreuse/filters/StudentFilter.class
./WEB-INF/classes/ch/cpnv/timbreuse/filters/TeacherFilter.java
./WEB-INF/classes/ch/cpnv/timbreuse/filters/ConnectionFilter.java
./WEB-INF/classes/ch/cpnv/timbreuse/filters/AdminFilter.java
./WEB-INF/classes/ch/cpnv/timbreuse/filters/AdminFilter.class
./WEB-INF/classes/ch/cpnv/timbreuse/filters/ConnectedFilter.java
./WEB-INF/classes/ch/cpnv/timbreuse/filters/TeacherFilter.class
./WEB-INF/classes/ch/cpnv/timbreuse/filters/StudentFilter.java
./WEB-INF/footer.jsp
./WEB-INF/.gitignore
./WEB-INF/lib
./WEB-INF/lib/bonecp-0.8.1-20131105.191813-1.jar
./WEB-INF/lib/jasypt-1.9.0.jar
./WEB-INF/lib/jstl-1.2.jar
./WEB-INF/lib/java-json.jar
./WEB-INF/lib/slf4j-api-1.6.6.jar
./WEB-INF/lib/joda-time-2.1.jar
./WEB-INF/lib/mysql-connector-java-5.1.38-bin.jar
./WEB-INF/lib/guava-13.0.1.jar
./WEB-INF/web.xml
./WEB-INF/connection.jsp
./connecting.jsp
./form.css
./META-INF
./META-INF/MANIFEST.MF
./teacher
./teacher/setTimeTable.jsp
./teacher/manageStudents.jsp
./teacher/setHolydays.jsp
./admin
./admin/adminPanel.jsp
How can I prevent that ?
The only objects that can be null are request and response, or dispatcher. If you can't place a breakpoint there, I would check tomcat's messages/logs before the exception
I at the time of running spark job in my project:
public static List<String> getAllSavedModelFoldersJob(String saveModelsFolderFilePath) {
JavaSparkContext ctx = null;
List<String> list = new ArrayList<String>();
try {
ctx = new JavaSparkContext(
new SparkConf().setAppName("Save Models into File").setMaster("local"));
list = getAllSavedModelFolders(ctx, saveModelsFolderFilePath).collect();
} catch (Exception e) {
e.printStackTrace();
return list;
} finally { // ctx.stop(); } return list; }
}
But getting below error,
java.lang.ClassNotFoundException: org.apache.spark.launcher.LauncherProtocol$Message
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1720)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571)
at org.apache.spark.scheduler.local.LocalBackend.(LocalBackend.scala:107)
at org.apache.spark.SparkContext$.org$apache$spark$SparkContext$$createTaskScheduler(SparkContext.scala:2603)
at org.apache.spark.SparkContext.(SparkContext.scala:522)
at org.apache.spark.api.java.JavaSparkContext.(JavaSparkContext.scala:59)
at com.nuevora.core.spark.SaveModelsJob.getAllSavedModelFoldersJob(SaveModelsJob.java:257)
at com.nuevora.controllers.FormsValidatorServlet.service(FormsValidatorServlet.java:546)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
I am using spark version is spark-1.6,hadoop2.6 and java1.8.
I am trying to set a cookie with user attribute values that I get from an Identity server. I am getting the user attributes but unable to set cookie. Can you someone tell me what is the mistake that I am doing?.
Here is my Java Code:
public class CircleArea extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
System.out.println("Server name is: " + request.getServerName());
System.out.println("Requesting cookies...");
Cookie[] cookies = request.getCookies();
String targetResourceURL = request.getRequestURL().toString();
if (cookies == null) {
System.out.println("Cookies are not present");
System.out.println("Requesting reference value...");
String refValue = request.getParameter("REF");
if (refValue == null) {
System.out.println("Reference value is null...");
System.out.println("Redirecting to URL: " + Configurations.PF_BASE_URL + ":"
+ Configurations.PF_PRIMARY_SSL_PORT + Configurations.PF_START_SSO_ENDPOINT + "?"
+ "PartnerIdpId=" + Configurations.PARTNER_ENTITY_ID + "&TargetResource=" + targetResourceURL);
response.sendRedirect(Configurations.PF_BASE_URL + ":" + Configurations.PF_PRIMARY_SSL_PORT
+ Configurations.PF_START_SSO_ENDPOINT + "?" + "PartnerIdpId="
+ Configurations.PARTNER_ENTITY_ID + "&TargetResource=" + targetResourceURL);
} else {
try {
System.out.println("Reference Value is: " + refValue);
System.out.println("Getting user attributes...");
Map<String, String> userAttrs = UserAttributes.pickUpAttributesFromReferenceIdAdapter(refValue);
for(Map.Entry<String, String> userAttr : userAttrs.entrySet()){
System.out.println("Key: " + userAttr.getKey() + " Value: " + userAttr.getValue());
}
System.out.println("Creating cookie with user attribute displayname Value...");
System.out.println("Cookie name is : " + targetResourceURL.substring(38));
Cookie cookie = new Cookie(targetResourceURL.substring(38), userAttrs.get("displayName"));
System.out.println("Setting cookie path to :" + targetResourceURL);
cookie.setPath(targetResourceURL);
System.out.println("Setting cookie age...");
System.out.println("Cookie will be deleted atonce when the browser is closed");
cookie.setMaxAge(-1);
response.addCookie(cookie);
RequestDispatcher dispatch = request.getRequestDispatcher("/area.jsp");
dispatch.forward(request, response);
} catch (Throwable any) {
any.printStackTrace();
}
}
}
}
public double calculateArea() {
Random rnd = new Random();
int radius = rnd.nextInt(15);
double area = Math.pow((double) radius, (double) 2) * Math.PI;
return area;
}
}
Here is my area.jsp:
<%# page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1" session="false"%>
<%# page import="com.pegright.seleniumproject.controllers.CircleArea"%>
<%# page import="javax.servlet.http.Cookie;"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Area</title>
</head>
<body>
<%
CircleArea area = new CircleArea();
Cookie[] cookie = request.getCookies();
for (int i = 0; i < cookie.length; i++) {
out.println("Welcome " + cookie[i].getValue());
}
out.println("Area of a random circle: " + area.calculateArea());
%>
</body>
</html>
I am getting the following error when I am accessing the application in browser:
Oct 07, 2015 5:50:40 PM org.apache.catalina.core.ApplicationDispatcher invoke
SEVERE: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at org.apache.jsp.area_jsp._jspService(area_jsp.java:76)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:748)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:486)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:411)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at com.pegright.seleniumproject.controllers.CircleArea.service(CircleArea.java:54)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
org.apache.jasper.JasperException: java.lang.NullPointerException
at org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:549)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:748)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:486)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:411)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:338)
at com.pegright.seleniumproject.controllers.CircleArea.service(CircleArea.java:54)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
at org.apache.jsp.area_jsp._jspService(area_jsp.java:76)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
... 33 more
I think I know the root cause. Cookies created in the Servlet via response.addCookie won't be available yet on a request dispatch.
You can use response.sendRedirect instead.
Remove these lines:
RequestDispatcher dispatch = request.getRequestDispatcher("/area.jsp");
dispatch.forward(request, response);
and replace with:
response.sendRedirect("area.jsp");
I am currently working on a small addresstable with vaadin, just to get to know vaadin a little. I have run into a problem, where I want to sort the entries of my table manually. The problem is, that I get a NullPointerException when i try to do this:
item.getItemProperty(Columns.NAME).getValue()
I have tried a few things here. I checked item and item isn't null, neither is item.getItemProperty(Columns.NAME) null. So when I try to make an if I still get a NullPointerException
if(item.getItemProperty(Columns.NAME).getValue() == null){}
The value is null and I understand that, but I want to give this value to an other item and I have no idea how to.
SEVERE: Servlet.service() for servlet [com.example.addresstable.AddresstableUI$Servlet] in context with path [/Addresstable] threw exception [com.vaadin.server.ServiceException: java.lang.NullPointerException] with root cause
java.lang.NullPointerException
at com.vaadin.data.util.IndexedContainer$IndexedContainerProperty.getValue(IndexedContainer.java:898)
at com.example.addresstable.AddressTable.addAddressToTable(AddressTable.java:114)
at com.example.addresstable.AddresstableUI.init(AddresstableUI.java:26)
at com.vaadin.ui.UI.doInit(UI.java:639)
at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:222)
at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74)
at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1402)
at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:305)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
IndexedContainer's Items are IndexedContainerItem.
When call it's getItemProperty the result is never null:
#Override
public Property getItemProperty(Object id) {
return new IndexedContainerProperty(itemId, id);
}
But when you call Property's getValue it may be null if there is no itemId or propertyId:
#Override
public T getValue() {
return (T) items.get(itemId).get(propertyId);
}
Probably it is a Vaadin bug: link
EDIT
If you want to check the container contains the item, you can do this:
public class MyIndexedContainer extends IndexedContainer {
#Override
public Item getUnfilteredItem(Object itemId) { // make it public
return super.getUnfilteredItem(itemId);
}
}
then
Table table = new Table();
MyIndexedContainer mic = new MyIndexedContainer();
table.setContainerDataSource(mic);
//...
// check that the container contains the item
if (mic.getUnfilteredItem(item) != null) {
//...
}