Use this list of common coding errors to help students debug.
Share Use this list of common coding errors to help students debug. with FacebookShare Use this list of common coding errors to help students debug. with Twitter
- Debugging is hard, knowing common mistakes can make it much easier to help students.
- Common errors include the following:
- Not naming a class the same as saved file name.
- Case sensitive typos.
- Using the number 1 versus the letter l. Especially in the Java print statement, System.out.println("Text Here");.
- Using a semicolon— ; —after a while statement.
- Putting a return type with constructors.
- Confusion regarding the order of operations.
- Messing up braces: using {} instead of [] or ().
- Putting parenthesis after the length method for Arrays in Java, it’s just .length without parenthesis.
- Students get really confused here because the Java method .size() for ArrayList has parentheses.
- With interface, students don’t realize you don’t need abstract in front of every method
- Confusion with implement versus extend, often saying "extend" when they mean implement.
- Confusion with super.method() and super(), the constructor call.
- This needs to be rote memorized, practiced, and reinforced frequently.
- Forgetting curly braces {} with loops.
- Out of bounds errors in loops. Looping to x+1 when students only need to loop to x-1.
- If you don’t minus one from the last element you want to look at you go out of bounds.
- Modulo, when students see modular arithmetic (e.g., 7%2) they cannot remember which number divides which.