package test;public class TotalSum {
public void totalSum(int x , int y){
int total = x + y;
System.out.println("int类型的结果:"+x+" + "+y+" = "+total);
}
public void totalSum(float x , float y){
float total = x + y;
System.out.println("float类型的结果:"+total);
}
public void totalSum(double x, double y){
double total = x + y;
System.out.println("double类型的结果:"+total);
}
public void totalSum(char x, char y){
char total = 'x'+ 'y' ;
System.out.println("字符类型的结果:"+total);
}
public static void main(String[] args){
TotalSum myobject = new TotalSum();
myobject.totalSum(3.2 , 5.3);
myobject.totalSum(3f,5f);
myobject.totalSum(6,3);
myobject.totalSum('3','3'); }
}
public void totalSum(int x , int y){
int total = x + y;
System.out.println("int类型的结果:"+x+" + "+y+" = "+total);
}
public void totalSum(float x , float y){
float total = x + y;
System.out.println("float类型的结果:"+total);
}
public void totalSum(double x, double y){
double total = x + y;
System.out.println("double类型的结果:"+total);
}
public void totalSum(char x, char y){
char total = 'x'+ 'y' ;
System.out.println("字符类型的结果:"+total);
}
public static void main(String[] args){
TotalSum myobject = new TotalSum();
myobject.totalSum(3.2 , 5.3);
myobject.totalSum(3f,5f);
myobject.totalSum(6,3);
myobject.totalSum('3','3'); }
}
char total = x+y;
System.out.println("字符类型的结果:"+total);
} >>这是你的原意吧,但是会出错!'x'+'y' 加法相当与2个整数相加,得到一个整数,已经超出127,属于一个不能显示的字符,?你可以测试以下2行代码的输出结果:
System.out.println('3');
System.out.println((int)'3');
float类型的结果:8.0
int类型的结果:6 + 3 = 9
Exception in thread "main" java.lang.Error: 无法解析的编译问题:
类型不匹配:不能从 int 转换为 char at test.TotalSum.totalSum(TotalSum.java:18)
at test.TotalSum.main(TotalSum.java:26)
”
System.out.println((int)'y');//输出 121
System.out.println((char)('x'+'y'));//输出 ?
System.out.println((char)(120+121));//输出 ?
int形 (占4个字节,范围大约是正负21亿左右)
120+121=241
0111,1000(120)
+ 0111,1001(121)
----------------------
1111,0001(241)
char型(-128 到 127)
120+121=-15
0111,1000(120)
+ 0111,1001(121)
----------------------
1111,0001(-15)System.out.println((char)-15);//所以输出“?”号其实,只要是负数,都一概是输出问号(?)的。