方法中的java逻辑问题
当我试图运行这段代码时,它总是返回错误的值,我无法找出哪里出错了。在我将10添加到catUp后,它会正确打印出来,但当我检查相同的值是否大于199时,由于某种原因,它会通过if语句。同样,当我在upCategory方法的末尾打印出来时,它给出了值1,但当我在main中打印出来时,它给出了值3方法中的java逻辑问题,java,logic,Java,Logic,当我试图运行这段代码时,它总是返回错误的值,我无法找出哪里出错了。在我将10添加到catUp后,它会正确打印出来,但当我检查相同的值是否大于199时,由于某种原因,它会通过if语句。同样,当我在upCategory方法的末尾打印出来时,它给出了值1,但当我在main中打印出来时,它给出了值3 public void upCategory() { double catUp = radioXM.getCurrentStaion(); catUp += 10; Syste
public void upCategory()
{
double catUp = radioXM.getCurrentStaion();
catUp += 10;
System.out.println(catUp);
if (catUp > 199.0);
{
catUp = 1;
radioXM.setCurrentStation(catUp);
System.out.println(catUp);
}
radioXM.setCurrentStation(catUp);
System.out.println(catUp);
}
public static void main (String [] args) {
AutoRadioSystem c = new AutoRadioSystem();
c.selectRadio();
double b = c.getCurrentStation();
System.out.println(b);
// this changes the radio to XM
c.selectRadio();
double d = c.getCurrentStation();
System.out.println(d);
//this is suppose to change the station up by 10 but gives incorrect value
c.upCategory();
double f = c.getCurrentStation();
System.out.println(f);
}
与之配套的其他代码
public abstract class Radio
{
double currentStation;
RadioSelectionBar radioSelectionBar;
public Radio()
{
this.currentStation = getMin_Station();
}
public abstract double getMax_Station();
public abstract double getMin_Station();
public abstract double getIncrement();
public void up()
{
}
public void down()
{
}
public double getCurrentStaion()
{
return this.currentStation;
}
public void setCurrentStation(double freq)
{
currentStation += freq;
}
public void setStation(int buttonNumber, double station)
{
}
public double getStation(int buttonNumber)
{
return 0.0;
}
public String toString()
{
String message = ("" + currentStation);
return message;
}
public boolean equals (Object o)
{
if (o == null)
return false;
if (! (o instanceof Radio))
return false;
Radio other = (Radio) o;
return this.currentStation == other.currentStation;
}
public class XMRadio extends Radio
{
private static final double Max_Station = 199;
private static final double Min_Station = 1;
private static final double Increment = 1;
public XMRadio()
{
}
public double getMax_Station()
{
return this.Max_Station;
}
public double getMin_Station()
{
return this.Min_Station;
}
public double getIncrement()
{
return this.Increment;
}
public String toString()
{
String message = ("XM "+ currentStation );
return message;
}
}
这条线就是问题所在:
if (catUp > 199.0);
Java将分号视为if
语句的主体,而if
下面大括号中的块将成为普通块,并始终执行
要将大括号中的块附加到if
语句,请删除分号:
if (catUp > 199.0)
这条线就是问题所在:
if (catUp > 199.0);
Java将分号视为if
语句的主体,而if
下面大括号中的块将成为普通块,并始终执行
要将大括号中的块附加到if
语句,请删除分号:
if (catUp > 199.0)