Weird null value problem
Hi,
I have this very weird problem (which I can't understand).
I have this applet that takes in values from the webpage.
private String[] collectParameters(){
String[] keys ={
"zero",
"one",
"two",
"three",
"four"
};
parameterArray =new String[keys.length];
for (int i = 0; i < keys.length; i++)
parameterArray[i] = getParameter(keys[i]);
return parameterArray;
}
Now parameter 3 might be a null value (i.e. ""), so I presume that it would have a null value.
Now this is the weird part. When I try to check if it is a null value, I keep getting very inconsistent answers.
I've try the following:
if (parameterArray[3] !=null)
//do whatever
if (!parameterArray[3].equals(null))
//do whatever
if (!String.valueOf(parameter[3]).equals(null))
//do whatever
but none of them work. I mean, if parameter 3 has no value some of them work and when it has a value they don't work (a null exception error occurs), which (I have to say) means that the if statement is not working.
And this code really is the weirdest
if (parameterArray[3] !=null)
//do whatever
it work on NetBeans but when I create the jar file and try to run it, I get a null exception error (this I really don't understand).
I've solved the problem by doing this
if (String.valueOf(parameter[3].length() > 4)
//do whatever
Which by itself is not elegant but hey it works.
I find it very odd. Is there a value stored in parameterArray[3] that I can't see because when I do a JOptionPane.showMessageDialog..., it come out empty (which doesn't mean it is null).
And the other thing is this, why if the length of parameter[3] = 4 when there is no value and >4 when there is?
What am I doing wrong?
Thanks.
Desmond
