java_规则
1.一个
.java文件中只能有一个public类。例如：此类只能有一个public类BicysleDemo
package bicly;
public class BicycleDemo {
public static void main(String[] args) {
Bicycle b1 = new Bicycle();
}
}
class Bicycle {
int cadence = 0;
public int getCadence() {
return cadence;
}
}