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Error using getParameterValues method

Scott Updike
Ranch Hand

Joined: Feb 16, 2006
Posts: 92
I have an issue that is probably more in line with a general Java question, but I'm writing a small servlet app and thought I would start here. I have a screen where people can select items to delete and if they don't select anything, I get a java.lang.NullPointerException error. Is there any way to test if my array variable deleteNames is null or not? In looking at the API, I know that if one element is returned, then the array length is equal to 1, but I don't know how to test the length if the original parameter was null.

I'm sure this is a simple thing to do, but I can't seem to find the right way to test if the array is populated or not.

My code snippet is below.

Thanks in advance.



String[] deleteNames = request.getParameterValues("deleteitems");
try {
Connection conn1 = (Connection) getServletContext().getAttribute("dbconn");
PreparedStatement stmt = conn1.prepareStatement("delete from baissue where issue_name = (?)");
PreparedStatement stmt1 = conn1.prepareStatement("delete from issue_comments where issue_name = (?)");

for (int i=0; i<deleteNames.length;i++) {
//Delete Comments
//Delete Issue

Ben Souther

Joined: Dec 11, 2004
Posts: 13410

Java API J2EE API Servlet Spec JSP Spec How to ask a question... Simple Servlet Examples jsonf
Dave Wingate
Ranch Hand

Joined: Mar 26, 2002
Posts: 262
Or if there's nothing to be done when no values are selected, you could try:

[ June 20, 2006: Message edited by: Dave Wingate ]

Fun programming etcetera!
Consider Paul's rocket mass heater.
subject: Error using getParameterValues method
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