Threads and classes

[richATrichardjones]

Hi

I have four classes in my prog. The first one is called MainProg.java and it coordinates the other three. The next one is called ProxyServer.java. It will eventually be a proxy server but at the moment all it does is return an array of size 4 of integers. The next is called ClientGUI.java which makes the GUI appear on the screen. The next is histogram.java which takes teh array from ProxySever.java and make a histogram of it. Without ProxyServer it works fine. With proxyServer only returning a single number (instead of an array) it works fine. However when it return an array it says there is a thread exception so doesnt even get to the ClientGUI and Histogram code.

To be clearer the order of events (all within main in MainProg.java) is as follows:

MainProg.java
|
|
|---- ProxyServer.java
|
|---- ClientGUI.java
|
|-----Histogram.java

The code in MainProg that calls ProxyServer is as follows:

ProxyServer myProx = new ProxyServer();
temp = ProxyServer.getArray();

The error is on the first line.

The code for ProxyServer is:

class public ProxyServer{

private int[] myArray;

public ProxyServer()
{
myArray[0] = 100;
myArray[1] = 100;
myArray[2] = 100;
myArray[3] = 100;
};

public int[] ProxyServer.getArray()
{
return myArray;
}
}


The error seems really odd. Like I said earlier the code all works when ProxyServer returns a single value but I get a thread exception when it returns and array.

Thanks for any help

Richard

 

[LloydV]

Hi,

you need to construct your array with....

myArray = new int[4];

in your ProxyServer() constructor before you assign values to it.

Also, you should probably declare
public int[] ProxyServer.getArray()
as
public int[] getArray()
(I'm assuming that long-term, you don't intend it to be a static method) and then reference it in MainProg like:
temp = myProx.getArray();

Hope that helps,
Lloyd

 

[richATrichardjones]

Thanks for the reply LloydV. I havent tried it but if it works it will help greatly

Cheers again

Richard