Question

java错误为过大的整数，怎么改这个啊？

public class TestConvert2
{
public static void main(String[] args)
{
int i = 1, j;
float f1 = 0.1; // 0.1f
float f2 = 123;
long l1 = 12345678, l2 = 8888888888;
double d1 = 2e20, d2 = 124;
byte b1 = 1, b2 = 2, b3 = 129;
j = j + 10;
i = i / 10;
i = i * 0.1;
char c1 = 'a', c2 = 125;
byte b = b1 - b2;
char c = c1 + c2 - 1;
float f3 = f1 + f2;
float f4 = f1 + f2 * 0.1;
double d = d1 * i + j;
float f = (float) (d1 * 5 + d2);
}
}

Answer 1

public class TestConvert2 {
public static void main(String[] args) {
int i = 1, j = 0;
float f1 = 0.1f; // 0.1f
float f2 = 123;
long l1 = 12345678, l2 = 8888888888l;
double d1 = 2e20, d2 = 124;
byte b1 = 1, b2 = 2, b3 = 127;
j = j + 10;
i = i / 10;
i = (int) (i * 0.1);
char c1 = 'a', c2 = 125;
byte b = (byte) (b1 - b2);
char c = (char) (c1 + c2 - 1);
float f3 = f1 + f2;
float f4 = (float) (f1 + f2 * 0.1);
double d = d1 * i + j;
float f = (float) (d1 * 5 + d2);

}

Answer 2

long l1 = 12345678L, l2 = 888888888L 长整型long需在末尾加"L"

Answer 3

int i = 1, j;
初始值未定义
float f1 = 0.1;
float f2 = 123;
应当为0.1f;强转一下
byte b1 = 1, b2 = 2, b3 = 129;
应当强转
c2 = 125;应当强转
float f3 = f1 + f2;
float f4 = f1 + f2 * 0.1;
应当强转

Answer 4

其实还是你对数据类型及最大值不太了解，看看这个部分，还有格式 float f2 =123 这个觉得也写的很不规范，123.0f,

Answer 5

将所有数值类型，都用BigDecimal类型