Simple try/catch array error

Programming Questions

adie.rect..

in Programming Questions • 1 year ago

So I am splitting data that comes in from a serial port and saving each piece as a separate part of the array. Later in the code I reference parts of the array that I saved. The array's length is either 1 or 12. When the length is 1 I can't reference the array for my display leading to errors, so I am trying to set it to catch the errors and force that part of the array to exist.

Below is the code I am trying to use and I keep getting unexpected '{' as an error....

try {
    text(Authourize[int(dataTypes[3])], 135, 50, 80, 25);//textboxes and choose the correct auth code
}
catch(ArrayIndexOutOfBoundsException e) {//catches if most sent but 3= number not in array
    dataTypes={"0","0","0","0"};
}
catch(NullPointerException e) {//catches if not enough sent ie 3 DNE
    dataTypes={"0","0","0","0"};
}

I tried to do the same thing with an if statement which is less preferable because then the program checks dataTypes on every loop, but I still get the same error...

if (dataTypes.length<3) {
dataTypes= {"0", "0", "0", "0"};
}
else if (int(dataTypes[3])>49) {
dataTypes[3]="0";
}

I know this is probably a really silly question but any help would be greatly appreciated.

Thanks in advance-
Adie

Replies(6)

benja

Re: Simple try/catch array error

1 year ago

dataTypes={"0","0","0","0"};

the problem is this line, you can only use this syntax when declaring an array-variable.

when the array already exists, you could either initiate it as a new array:

dataTypes = new String[]{"0", "0", "0", "0"};

or use Array.fill()

Arrays.fill(dataTypes, "0");

adie.rect..

Re: Simple try/catch array error

1 year ago

Thank you so much, I didn't realize I needed to do that! Do you know of a way to force the length to which Arrays.fill() extends?

benja

Re: Simple try/catch array error

1 year ago

You can pass additional parameters defining which part of the array should be filled, this code would start at index 0 and stop at index 3 (not changing the value at index 3).

Arrays.fill(dataTypes, 0, 3, "0");

But it's pretty much the same as looping through the array yourself and changing the values.

So Array.fill() doesn't change the size of your array you could create a new one of the size you want it to be.
Or use ArrayList instead which has methods for adding/removing elements.

adie.rect..

Re: Simple try/catch array error

1 year ago

Thank you so much!!! I got the last of the bugs in my program finally worked out!

PhiLho

Re: Simple try/catch array error

1 year ago

For the record, a try / catch structure is much slower than an if / else one... You should avoid to catch errors your can detect beforehand, ArrayIndexOutOfBoundsException and NullPointerException being particularly trivial to avoid (while IOException isn't avoidable).

adie.rect..

Re: Simple try/catch array error

1 year ago

Thank you so much as well! The out of bounds and null pointer were affecting my program the most by stopping the entire process so they were first on my list to work on, while I have yet to run into the other exception... although that is probably soon too change :) Also great information about the speed of try/catch, didnt know that.

Thank you both so much!

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