你有一個字面數值(literal number),帶有特殊含義.
創造一個常量,根據其意義為它命名,并將上述的字面數值替換為這個常量.
double potentialEnergy(double mass, double height) {
return mass * 9.81 * height;
}
double potentialEnergy(double mass, double height) {
return mass * GRAVITATIONAL_CONSTANT * height;
}
static final double GRAVITATIONAL_CONSTANT = 9.81;