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Java Java Objects (Retired) Harnessing the Power of Objects Helper Methods

Nathan Beauchamp
Nathan Beauchamp
2,456 Points

false == 0; ?

I'm setting my isBatteryEmpty return to return mBarsCount ==0; but because false == 0 could i just have the return read return !mBarsCount; I'm pretty sure this works in C++, but I have very little experience in Java.

Or just to be on the safe side, even though the mBarsCount should never be able to go bellow 0, should the return be return mBarsCount < 1;

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 charge() {
    mBarsCount = MAX_BARS;

  public boolean isBatteryEmpty() {
   return mBarsCount == 0; 

1 Answer

Dan Johnson
Dan Johnson
40,532 Points

Unlike in C/C++, conditional expressions must result in type boolean. There is no implicit conversion.

As for using mBarsCount < 1 instead, I would stick with mBarsCount == 0. Negative values would probably indicate a logic error somewhere else in the class which would need to be fixed, rather than be built around.