Thread: Need help with fixing this error: ArrayIndexOutOfBoundsException: 1

Here is my code for this method:
(for passed-in desc, it has format as "brand: model"
For example, if the brand is Whirlpool and the model is LX1279, the description will be Whirlpool:LX1279. If only the brand is set, the description should contain the brand followed by a colon. If only the model is set, the description should contain a colon followed by the model. If both the brand and the model are null, that is equivalent to a null description.)

public void setDescription(String desc)
{
if (desc == null)
{
throw new IllegalArgumentException
("description is null.");
}
else if (!desc.contains(":"))
{
throw new IllegalArgumentException
("description does not contain a colon.");
}
else if (desc.contains(":"))
{
String[] tok = new String[2];
tok = desc.split(":");

if (tok[0] != null && tok[1] != null)
{
appliance.setBrand(tok[0]);
appliance.setModel(tok[1]);
}


}
}
The error suggested the line that contains such problem is at line 53, which I highlighted with bold red color.

symptom: java.lang.ArrayIndexOutOfBoundsException: 1
at ApplianceAdapter.setDescription(ApplianceAdapter.j ava:53)

I am not really familiar with such error, but any hint/explanation/examples will be helpful.