的servlet抛出一个NPE着FIGUR为什么

-1

public class AddMovieServlet extends HttpServlet { 
private static final long serialVersionUID = 1L; 

/** 
* @see HttpServlet#HttpServlet() 
*/ 
public AddMovieServlet() { 
    super(); 
    // TODO Auto-generated constructor stub 
} 

@Override 
protected void doPost(HttpServletRequest req, HttpServletResponse resp) 
     throws ServletException, IOException { 
    super.doPost(req, resp); 

    process(req,resp); 
} 


@Override 
protected void doGet(HttpServletRequest req, HttpServletResponse resp) 
     throws ServletException, IOException { 
    // TODO Auto-generated method stub 
    super.doGet(req, resp); 
    process(req,resp); 
} 


//my process method 
protected void process(HttpServletRequest req , HttpServletResponse resp) 
{ 
    //we will set up requests of the elements of our movie 

    String name = req.getParameter("name"); 
    long date = Long.parseLong(req.getParameter("relDate").toString()); 
    String lang = req.getParameter("lang"); 
    int rating = Integer.parseInt(req.getParameter("rating")); 
    String descr = req.getParameter("descr"); 

    String DBURL = "jdbc:mysql://localhost:8080/moviedb"; 
    String query = "INSERT INTO movieTable VALUES (?,?,?,?,?)"; 

    Connection myConnection = null; 
    PreparedStatement myStatement = null; 

    try { 
     Class.forName("com.mysql.jdbc.Driver"); 
     myConnection = DriverManager.getConnection(DBURL,"root","root"); 
     myStatement = myConnection.prepareStatement(query); 
     myStatement.setString(1, name); 
     myStatement.setLong(2, (int)date); 
     myStatement.setString(3, lang); 
     myStatement.setInt(4, rating); 
     myStatement.setString(5, descr); 
     int insertedOrNot = myStatement.executeUpdate(); 
     System.out.println("inserted " + insertedOrNot); 
    } catch (ClassNotFoundException | SQLException e) { 
     // TODO Auto-generated catch block 
     e.printStackTrace(); 
    }finally 
    { 
     try { 
      if(myConnection!=null) 
       myConnection.close(); 
     } catch (SQLException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } 
    } 

}

}的servlet抛出一个NPE着FIGUR为什么

SEVERE: Servlet.service() for servlet AddMovieServlet threw exception 
java.lang.NullPointerException 
at wimc.serv.AddMovieServlet.process(AddMovieServlet.java:52) 
at wimc.serv.AddMovieServlet.doGet(AddMovieServlet.java:42) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) 
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:102) 
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298) 
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857) 
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588) 
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) 
at java.lang.Thread.run(Unknown Source)

来源

2013-05-12 user1705576

你能指向你的代码中的第52行吗？ – 2013-05-12 23:14:30

req.getParameter（“relDate”）返回null。我建议你远程调试并逐步完成。 – BevynQ 2013-05-12 23:18:30

什么变量为空？ – 2013-05-12 23:23:14

req.getParameter("relDate")返回null。

来源

2013-05-12 23:40:09

以及最新的修复？ – user1705576 2013-05-12 23:56:17

的servlet抛出一个NPE着FIGUR为什么

回答

相关问题