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copying string arrays returned from function(urgent)

 
Greenhorn
Posts: 20
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Hi
I have 2 classes as follows:
public class A
{
String sv[] = new String[1000];
// Add values into sv.............
.........................
.........................
.........................
B k = new B(); // Call Class B
B.cards_output(sv); // invoke a method in Class B
} // End of Class A
public class B
{
// general declaration
public String copy_sv[] = new String[1000];
......
......
......
......
public void cards_output(String sv[]) // function in class B
{
for(int i=0;i<sv.length();i++)
{
copy_sv=sv;
}
}
} // End of Class B
I can only use copy_sv[] only in the functions that i pass that value to, I need copy_sv[] to be accessible everywhere in the program.
Now when ever I try to make a reference to copy_sv[] elsewhere in the program I am getting a Null pointer exception.
I tried using cloneable interface with clone method but again got a null pointer exception.
 
Chicken Farmer ()
Posts: 1932
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I don't think this is really an I/O or Streams issue, but we'll dig a bit deeper and find out the problem anyway.
I take it that these are static members in B, right? So B.cards_output won't work.
Also, where are you getting the NullPointerException exactly? Are you creating new instances of B and then doing someBInstance.copy_sv?
 
Wanderer
Posts: 18671
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Sharath, please don't post the same question in multiple forums. It wastes time for evceryone involved if they aren't aware of other answers that have been posted. Please post follow-ups here. Thanks.
 
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