When dealing with an object that could potentially be null, or some of its fields, don't just check the field for null, check the object first. Checking that a null object's field is not null will give you a Null Pointer Exception. Check the Object itself first!
When you hit a condition in a loop and you want to skip to the next item in the loop, don't use break; Use continue; break; gets you completely out of the loop. I knew that, but one stupid mistake like that could be the difference between the lunar module landing perfectly, or crashing in flames into a pile of moon dust!