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Start your free trialSimon Shour
545 PointsNeed help with incrementing mBarsCount in while loop.
I can't seem to set up my while loop properly. I think I must be missing a step. If anyone can take a look and tell me what I am doing wrong that would be great.
public class GoKart {
public static final int MAX_ENERGY_BARS = 8;
private String mColor;
private int mBarsCount;
public GoKart(String color) {
mColor = color;
mBarsCount = 0;
}
public boolean charging(){
boolean isFullyCharged = false;
if (!isBatteryEmpty()){
mBarsCount++;
isFullyCharged = true;
}
while (mBarsCount.charge()){
System.out.println("Charged!");
}
return isFullyCharged;
}
public String getColor() {
return mColor;
}
public void charge() {
mBarsCount = MAX_ENERGY_BARS;
}
public boolean isBatteryEmpty() {
return mBarsCount == 0;
}
public boolean isFullyCharged() {
return mBarsCount == MAX_ENERGY_BARS;
}
}
2 Answers
Dan Johnson
40,533 PointsIn this challenge you're actually redefining the charge method, so all the new code will go there.
Here's an outline showing how to leverage the new helper method:
public void charge() {
// While the GoKart is not fully charged:
// increment mBarsCount
}
The conditional used with the while loop will handle the termination so you won't need a separate if statement.
Matthew Day
3,397 PointsAs Dan Johnson said, you will be redefining the charge
method. You will need to replace
mBarsCount = MAX_ENERGY_BARS;
with a while loop.
There is a tutorial on while loops and do-while loops here if you need more help understanding them.
A while loop looks like the following:
while ( an expression that determines whether the code below gets executed goes here) {
//the code to execute while the expression is true goes here
}
Since the !
operator means "not", and you already have a isFullyCharged()
method that checks to see if mBarsCount
is full, you can use !isFullyCharged
between the parenthesis like so:
while ( !isFullyCharged()) {
//the code to execute while the expression is true goes here
}
This runs the code in the curly braces while mBarsCount
is not full.
Finally, since you need to increase mBarsCount
by one, you can use
mBarsCount ++;
between the curly braces like so:
while ( !isFullyCharged()) {
mBarsCount ++;
}