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Pauliina K
1,973 PointsIllegalArgumentException
I get an error here that I don't understand. I can't see the error in the preview, a note just comes up saying: "Bummer! Make sure you throw the exception before change the mBarsCount field." So I'm guessing I put my exception i the wrong place, but then where is the right?
--
public class GoKart {
public static final int MAX_BARS = 8;
private String mColor;
private int mBarsCount;
public GoKart(String color) {
mColor = color;
mBarsCount = 0;
}
public String getColor() {
return mColor;
}
public void drive() {
drive(1);
}
public void drive(int laps) {
// Other driving code omitted for clarity purposes
mBarsCount -= laps;
throw new IllegalArgumentException("Not enough battery remains") {
};
}
public void charge() {
while (!isFullyCharged()) {
mBarsCount++;
}
}
public boolean isBatteryEmpty() {
return mBarsCount == 0;
}
public boolean isFullyCharged() {
return mBarsCount == MAX_BARS;
}
}
PS. I don't understand how you make it look like code here in the comments? Just some parts looks right or it looks like this.
1 Answer
Steve Hunter
57,712 PointsHi Pauliina,
You need to see if laps is greater than mBarsCount. If it is, throw the exception; else do the deduction:
public void drive(int laps) {
// Other driving code omitted for clarity purposes
if(laps > mBarsCount) {
throw new IllegalArgumentException("Not enough battery remains");
} else {
mBarsCount -= laps;
}
}
Make sense?
Steve.
Pauliina K
1,973 PointsAhhh! I was so close!! I had everything except the else mBarsCount -= laps;
Btw, how do you make the code look like code here in the comments? I can't seem to get it right, hehe.
Steve Hunter
57,712 PointsYou were very close, yes!
To get the code to look like code, use three backticks (top left on a Windows keyboard, underneath escape) then the language name.
Close the code block with another three backticks on their own.
I edited your initial post so if you go and hit the three dots, and select Edit, you'll see what I added to make it work.
Steve.
Pauliina K
1,973 PointsAwesome! Thanks again Steve!
Steve Hunter
57,712 PointsNo problem. :-)
Pauliina K
1,973 PointsPauliina K
1,973 PointsUgh.. I tried to put the exception under the other drive-method, but I then got this error message instead:
"Bummer! Are you sure you threw the IllegalArgumentException if the requested amount of laps would make the battery less than zero?"
I don't get it. Where is it supposed to be then? Isn't this all the code you need to throw an exception? throw new IllegalArgumentException("Not enough battery remains")
Or do I need to add something? I tried adding a "if(laps > mBarsCount)", but that didn't work either.
-- Steve Hunter, do you know what I'm doing wrong? (I don't know anyone else here, and you've helped me before)