程序2-3
import java.util.*;
public class DataType{
public static void main(String[] args){
boolean flag;
char yeschar;
byte finbyte;
int intvalue;
long longvalue;
short shortvalue;
float floatvalue;
double doublevalue;

flag = true;
yeschar = 'y';
finbyte = 30;
intvalue = -70000;
longvalue = 200l;
shortvalue = 20000;
floatvalue = 9.997E-5f;
doublevalue = floatvalue * floatvalue;
System.out.println("The values are:");
System.out.println("布尔类型变量 flag = " + flag);
System.out.println("字符类型变量 yeschar = " + yeschar);
System.out.println("字节类型变量 finbyte= " + finbyte);
System.out.println("整型变量 intvalue= " + intvalue);
System.out.println("长整型变量 longvalue= " + longvalue);
System.out.println("短整型变量 shortvalue= " + shortvalue);
System.out.println("浮点型变量 floatvalue= " + floatvalue);
System.out.println("双精度浮点型变量 doublevalue= " + doublevalue);
}
}