White Devil
New Member
Please help me to identify why I always got this error :\[code\] java.lang.NullPointerException at TaskDAO.TaskDAO.main(TaskDAO.java:34)\[/code\]Note: \[code\]DatebaseHelper\[/code\] is a class which is using JDBC to connect to MySQL.\[code\]import java.sql.SQLException;import java.text.SimpleDateFormat;import TaskManagement.*;public class TaskDAO { DatabaseHelper help; public static void main(String[] args) throws InstantiationException, IllegalAccessException, ClassNotFoundException, SQLException { TaskDAO taskDAO = new TaskDAO(); int taskID = 6; String subject = "lau cua"; Status status = Status.Completeted; Priority priority = Priority.High; Float percentage = 4f; String tableName = "tasks"; String startDate = "2012/11/11"; String dueDate = "2012/11/12"; String query = "INSERT INTO " + tableName + "(taskID,subject,status,priority,percentage,startDate,dueDate)" + " VALUES ('" + taskID + "'," + "'" + subject + "'," + "'" + status + "'," + "'" + priority + "'," + "'" + percentage + "'," + "'" + startDate + "'," + "'" + dueDate + "')"; taskDAO.help.executeQuery(query); }}\[/code\]