| 类型 | bits/byte | 范围 | 默认值 |
| byte | 8/1 | -128 +127 | 0 |
| short | 16/2 | -32,768 +32,767 | 0 |
| int | 32/4 | -2,147,483,648 = -231 +2,147,483,647 = 231-1 | 0 |
| long | 64/8 | -9,223,372,036,854,775,808 = -263 +9,223,372,036,854,775,807 = 263-1 | 0L |
| float | 32/4 | 1.40129846432481707e-45 = 2-149 3.40282346638528860e+38 = (2-2-23)·2127 | 0.0f |
| double | 64/8 | 4.94065645841246544e-324d = 2-1074 1.79769313486231570e+308d = (2-2-52)·21023 | 0.0d |
| char | 16/2 | 0 = U+0000 65,535 = U+10FFFF | 0 |
| boolean | 1 | true or false | false |
float 和 double 都不能用于表示精确值，推荐用 Java.Math.BigDecimal
// normal statement byte myInt8 = 2; short myInt16 = 1; int myInt32 = 0; long myInt64 = -1; //using octal or hexadecimal notation int myHex = 0xF; // hexadecimal (base 16) int myOct = 07; // octal (base 8) //double 类型 double myDouble = 3.14; double myDouble2 = 3e2; //float 如果你没有节省空间的需求,还是用double吧 float myFloat = 3.14; //error float myFloat = (float)3.14; float myFloat = 3.14F; //char type char myChar = ‘A‘ char myChar = ‘\u0000‘; //boolean type boolean myBool = false;
Java 语法 索引 ----- 变量-----数据类型,布布扣,bubuko.com
原文：http://www.cnblogs.com/timba/p/3900437.html