help with nullPointerException tomcat
I have made a catalog using a servlet but when i try to run it i just get this in the browser:
java.lang.NullPointerException
at coreservlets.Catalog.getItem(Catalog.java:18)
at coreservlets.CatalogPage.setItems(CatalogPage.java :40)
at coreservlets.KidsBooksPage.init(KidsBooksPage.java :16)
at javax.servlet.GenericServlet.init(GenericServlet.j ava:258)
at org.apache.catalina.core.StandardWrapper.loadServl et(StandardWrapper.java:918)
at org.apache.catalina.core.StandardWrapper.allocate( StandardWrapper.java:655)
at org.apache.catalina.servlets.InvokerServlet.serveR equest(InvokerServlet.java:400)
at org.apache.catalina.servlets.InvokerServlet.doGet( InvokerServlet.java:180)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:740)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:853)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:193)
at filters.ExampleFilter.doFilter(ExampleFilter.java: 149)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:193)
at filters.ExampleFilter.doFilter(ExampleFilter.java: 149)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invo ke(StandardWrapperValve.java:243)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(Cont ainerBase.java:943)
at org.apache.catalina.core.StandardContextValve.invo ke(StandardContextValve.java:190)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:566)
at org.apache.catalina.authenticator.AuthenticatorBas e.invoke(AuthenticatorBase.java:475)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:564)
at org.apache.catalina.valves.CertificatesValve.invok e(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(Cont ainerBase.java:943)
at org.apache.catalina.core.StandardContext.invoke(St andardContext.java:2347)
at org.apache.catalina.core.StandardHostValve.invoke( StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:566)
at org.apache.catalina.valves.ErrorDispatcherValve.in voke(ErrorDispatcherValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:564)
at org.apache.catalina.valves.ErrorReportValve.invoke (ErrorReportValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:564)
at org.apache.catalina.valves.AccessLogValve.invoke(A ccessLogValve.java:468)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(Cont ainerBase.java:943)
at org.apache.catalina.core.StandardEngineValve.invok e(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline.invokeNe xt(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(Cont ainerBase.java:943)
at org.apache.catalina.connector.http.HttpProcessor.p rocess(HttpProcessor.java:1027)
at org.apache.catalina.connector.http.HttpProcessor.r un(HttpProcessor.java:1125)
at java.lang.Thread.run(Thread.java:595)
can anyone explain to me what would cause this i think it has something to do with this peice of code:
for(int i=0; i<items.length; i++) {
out.println("");
printitem = items[i];
if (printitem == null) {
out.println("" +
"Unknown recording ID " +
"");
} else {
added[i] = items[i];
out.println( added[i] + "\n" +
item.gettitle() + "\n" +
item.getprice() + "\n" +
item.getdirector() + "\n" +
item.getcategory() + "\n" +
item.getduration() + "\n" +
item.getrating() + "\n" +
item.getyear() + "\n");
out.println("\n</BODY></HTML>");
}
}
please any help would be excellent i need to get this working soon lol its driving me mad!!!!!! Below is my servlet file
package coreservlets;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class Catalog extends HttpServlet {
private static CatalogItem added[];
private static CatalogItem[] items;
CatalogItem item;
CatalogItem details;
public static CatalogItem getItem(int recordingid) {
CatalogItem item;
for(int i=0; i<items.length; i++) {
item = items[i];
if (recordingid==item.getrecordingid()) {
return(item);
}
}
return(null);
}
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
Connection conn = null;
String imageDB;
String titleDB;
String directorDB;
String categoryDB;
int durationDB;
String ratingDB;
String yearDB;
float priceDB;
int recordingidDB;
try{
Class.forName("com.mysql.jdbc.Driver").newInstance ();
} catch(Exception e) {
System.out.println(e);
}
try{
conn = DriverManager.getConnection
("jdbc:my sql url goes here");
}
catch(SQLException se) {
System.out.println(se);
}
try{
String selectSQL = "select image_name, title, director, category, duration, rating, year_released, price, recording_id "+
"from video_recordings ";
Statement stmt = conn.createStatement();
ResultSet rs1 = stmt.executeQuery(selectSQL);
// Retrieve the results
while(rs1.next()){
recordingidDB = rs1.getInt("recording_id");
imageDB = rs1.getString("image_name");
titleDB = rs1.getString("title");
directorDB = rs1.getString("director");
categoryDB = rs1.getString("category");
durationDB = rs1.getInt("duration");
ratingDB = rs1.getString("rating");
yearDB = rs1.getString("year_released");
priceDB = rs1.getFloat("price");
double priceD = priceDB;
item =
new CatalogItem
(recordingidDB,
titleDB,
directorDB,
categoryDB,
durationDB,
ratingDB,
yearDB,
priceD);
}
String title = "Catalog";
out.println( "<HTML>\n" +
"<HEAD><TITLE>" + title + "</TITLE></HEAD>\n" +
"<H1 ALIGN=\"CENTER\">" + title + "</H1>");
for(int i=0; i<items.length; i++) {
out.println("");
details = items[i];
if (details == null) {
out.println("
sorry an error "
);
} else {
added[i] = items[i];
out.println( added[i] + "\n" +
item.gettitle() + "\n" +
item.getprice() + "\n" +
item.getdirector() + "\n" +
item.getcategory() + "\n" +
item.getduration() + "\n" +
item.getrating() + "\n" +
item.getyear() + "\n");
out.println("\n</BODY></HTML>");
}
}
// Close the stament and database connection
// (must remember to always do this)
stmt.close();
conn.close();
} catch(SQLException se) {
System.out.println(se);
}
}
}
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