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Error using getParameterValues method

 
Scott Updike
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Posts: 92
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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.

Scott

-------------------------

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
stmt1.setString(1,deleteNames[i]);
stmt1.executeUpdate();
//Delete Issue
stmt.setString(1,deleteNames[i]);
stmt.executeUpdate();
}

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Ben Souther
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Dave Wingate
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Or if there's nothing to be done when no values are selected, you could try:


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