若有错误,欢迎指正。
Java基本数据类型一共有八种:
byte、short、int、long、float、double、char、boolean
名称 | 所占字节 | 数据范围 | 默认值 |
---|---|---|---|
byte(字节型) | 1 | (-2^7, 2^7 - 1) | 0 |
short(短整型) | 2 | (-2^13, 2^13 - 1) | 0 |
int(整型) | 4 | (-2^31, 2^31 - 1) | 0 |
long(长整型) | 8 | (-2^63, 2^63 - 1) | 0 |
float(单精度浮点型) | 4 | (1.4E-45, 3.4028235E38) | 0.0 |
double(双精度浮点型) | 8 | (4.9E-324, 1.7976931348623157E308) | 0.0 |
char (字符型) | 2 | Unicode中0-65535表示的字符 | 空字符 |
boolean(布尔型) | 1 | (false, true) | false |
以下代码使用他们对应的封装类型表示的一些范围或者是一些值。
public class Test{
public static void main(String[] args) {
byte byteNum = 10;
System.out.println(byteNum);
System.out.println(Byte.MAX_VALUE);
System.out.println(Byte.MIN_VALUE);
System.out.println("===================");
short shortNum = 10;
System.out.println(shortNum);
System.out.println(Short.MAX_VALUE);
System.out.println(Short.MIN_VALUE);
System.out.println("====================");
int num = 10;
System.out.println(num);
System.out.println(Integer.MAX_VALUE);
System.out.println(Integer.MIN_VALUE);
System.out.println("==================");
long longNum = 10L;
System.out.println(longNum);
System.out.println(Long.MAX_VALUE);
System.out.println(Long.MIN_VALUE);
System.out.println("==================");
float floatNum = 10.5f;
System.out.println(floatNum);
System.out.println(Float.MAX_VALUE);
System.out.println(Float.MIN_VALUE);
System.out.println("====================");
double doubleNum = 10.5;
System.out.println(doubleNum);
System.out.println(Double.MAX_VALUE);
System.out.println(Double.MIN_VALUE);
System.out.println("====================");
char c = 'A';
System.out.println(c);
System.out.println(Character.MAX_VALUE);
System.out.println(Character.MIN_VALUE);
System.out.println("=====================");
boolean b = false;
System.out.println(b);
}
}
10
127
-128
===================
10
32767
-32768
====================
10
2147483647
-2147483648
==================
10
9223372036854775807
-9223372036854775808
==================
10.5
3.4028235E38
1.4E-45
====================
10.5
1.7976931348623157E308
4.9E-324
====================
A
=====================
false