public class LocationTest {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Location l1=new Location(1.0,1.0);
Location l2=new Location(0.0,0.0);
//Location.distance(l1,l2);
System.out.println(Location.distance(l1,l2));
//System.out.println(Location.);
Location l3=Location.midpoint(l1,l2);
String str=l3.toString();
System.out.println( "它们的中点是： "+str);
}
}
class Location
{
private static double x,y;
public Location(double x,double y)
{
this.x=x;
this.y=y;
}
public static double distance(Location p1,Location p2)
{
double a,b;
if((p1==null)||(p2==null))
return Double.NaN;
a=p1.x-p2.x;
b=p1.y-p2.y;
return Math.sqrt(a*a+b*b);
//System.out.println((double)Math.sqrt(a*a+b*b));
}
public static Location midpoint(Location p1,Location p2)
{
double xNew=0,yNew=0;
if((p1==null)||(p2==null));
return null;
xNew=(p1.x/2.0)+(p2.x/2.0);
yNew=(p1.y/2.0)+(p2.y/2.0);
return new Location(xNew,yNew);
}
}
我写的这个程序本意是求两个点之间的距离以及中点坐标，但输出结果是错误的。另外“ xNew=(p1.x/2.0)+(p2.x/2.0);
yNew=(p1.y/2.0)+(p2.y/2.0);”
这两句提示：
Exception in thread "main " java.lang.Error: Unresolved compilation problem:
Unreachable code
at com.blackstars.Location.midpoint(LocationTest.java:45)
at com.blackstars.LocationTest.main(LocationTest.java:15)
请问这是什么原因？怎么才能得到正确的结果？请高手指教。。。
------解决方案--------------------
if((p1==null)||(p2==null)); //这句的分号去掉
------解决方案--------------------
package net.rubyeye.javabean;
public class LocationTest {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Location l1 = new Location(1.0, 1.0);
Location l2 = new Location(0.0, 0.0);
// Location.distance(l1,l2);
System.out.println(Location.distance(l1, l2));
// System.out.println(Location.);
Location l3 = Location.midpoint(l1, l2);
String str = l3.toString();
System.out.println( "它们的中点是： " + str);
}
}
class Location {
private double x, y;
public Location(double x, double y) {
this.x = x;
this.y = y;
}
public static double distance(Location p1, Location p2) {
double a, b;
if ((p1 == null) || (p2 == null))
return Double.NaN;
a = p1.x - p2.x;
b = p1.y - p2.y;
return Math.sqrt(a * a + b * b);
// System.out.println((double)Math.sqrt(a*a+b*b));
}
public static Location midpoint(Location p1, Location p2) {
double xNew = 0, yNew = 0;
if ((p1 == null) || (p2 == null))
return null;
xNew = (p1.x / 2.0) + (p2.x / 2.0);