Java Bean not working as expected
OK, I have a JSP running the following script section.
<% irCollection mgrq = new irCollection();
mgrq.setMgrid("Chris Novish");
mgrq.populateCollection();
int pagenum;
if (request.getParameter("p") != null) {
String pagedatum=request.getParameter("p");
pagenum = Integer.parseInt(pagedatum);
} else { pagenum = 0; }
for (int i=0;i<10;i++) {
int rownum = pagenum * 10 + i;
InquireRecord currec = mgrq.getCurRecords(rownum);
out.println(currec.getID()); %>
irCollection has an ArrayList property that stores a several InquireRecord objects. It gets this data from a database using the mgrid as (set in line 2 there) as the matching term.
But I'm开发者_JS百科 getting an IndexOutOfBounds exception on what appears here as line 11.
I've done some tests, and I'm pretty sure that it's because populateCollection() isn't getting things done. I have a getSize method that gives me a size of 0.
I made a test class in Eclipse to make sure all my methods were working: package com.serco.inquire;
public class test {
public static void main (String[] args) {
String mgr = "Chris Novish";
irCollection bob = new irCollection();
bob.setMgrid(mgr);
bob.populateCollection();
InquireRecord fred = bob.getCurRecords(1);
System.out.println(fred.getID());
}
}
That test class produces exactly what I'd expect. Other than the names of some of the local variables, I can't see what I'm doign different in the JSP.
So... tell me, what noobish mistake did I make?
for the sake of being thorough, here's the populateCollection() method:
public void populateCollection() {
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String filename = "inquire.mdb";
String database = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=";
database+= filename.trim() + ";DriverID=22;READONLY=true}";
Connection con = DriverManager.getConnection( database ,"","");
Statement s = con.createStatement();
s.execute ("SELECT * FROM inquiries WHERE manager = '" + mgrid + "'");
ResultSet rs = s.getResultSet();
int cur;
if (rs != null) {
while (rs.next()) {
cur = rs.getRow();
cur -- ;
int curID = rs.getInt("ID");
this.newIR.setID(curID);
String cursub = rs.getString("submitter");
this.newIR.setSubmitter(cursub);
this.iRecords.add(cur, this.newIR);
}
this.size = iRecords.size();
this.pages = this.size / 10;
int remain = this.size % 10;
if (remain > 0) { this.pages++; }
} else { System.out.println("no records."); }
}
catch (Throwable e) {
System.out.println(e);
}
}
Your IndexOutOfBounds
exception is probably being caused by the value of rownum
being passed to mgrq.getCurRecords()
.
Your test code proves nothing because there you're calling getCurRecords()
with a constant which is probably always valid for your system and will never cause the exception.
My suggestion is to step through the code in your JSP with a debugger, or even simply to print out the value of your variables (especially pagedatum
, pagenum
and rownum
) in your JSP code.
Is your JSP Snippet correct? It looks like you started the braces for the
for (int i=0;i<10;i++) {
but I dont see a end braces for that at all. Can you check if that is the case and if so, fix the code appropriately?
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