第二章
public class Example2_1 {
public static void main (String args[]){
char c='a';
System.out.println("zimu"+c+"in the unicode canlender consition:"+(int)c);
System.out.println("zimubiao:");
for(int i=(int)c;i<c+25;i++){
System.out.print(""+(char)i);
}
}
}
public class Example2_2 {
public static void main (String args[]){
byte a=120;
short b=130;
int c=2200;
long d=8000;
float f;
double g=0.1234567812345678;
a=(byte)b;
c=(int)d;
f=(float)g;
System.out.println("a="+a);
System.out.println("b="+b);
System.out.println("c="+c);
System.out.println("d="+d);
}
}
public class Example2_3 {
public static void main (String args[]){
char c='A';
float f=123.456789f;
double d=123456.12345678;
long x=5678;
System.out.printf("%c%n10.3f%n%f,%12d%n%d",c,f,d,x,x=x+2);
}
}
import java.util.*;
public class Example2_4 {
public static void main(String arg[]){
Scanner reader=new Scanner(System.in);
double sum=0;
int m=0;
while(reader.hasNextDouble()){
double x=reader.nextDouble();
m=m+1;
sum=sum+x;
}
System.out.printf("%d个数的和为%f\n",m,sum);
System.out.printf("%d个数的平均值是%f\n",m,sum/m);
}
}
public class Example2_5 {
public static void main (String args[]){
int[]a={1,2,3};
int[]b={10,11};
System.out.println("address a:"+a);
System.out.println("address b:"+b);
System.out.printf("b[0]=%-3db[1]=%-3d\n",b[0],b[1]);
b=a;
System.out.println("address a"+a);
System.out.println("address b"+b);
b[1]=888;
b[2]=999;
System.out.printf("a[0]=%-5da[1]=%-5da[2]=%-5d\n",a[0],a[1],a[2]);
System.out.printf("b[0]=%-5da[1]=%-5da[2]=%-5d\n",b[0],b[1],b[2]);
}
}
问题:
Example2-3中,在编译和运行的时候都正常通过了。但是,通过上传的图片,也可以看到,在编译运行成功之后,还提示一段文字,应该是抛出异常的意思,也许是没有引包?异常处理还没有学到,再看看异常处理那里,看看可不可以找到问题吧。