Java字节数据类型

Question

在 Sun 的教程中它说了一个字节:

byte: The byte data type is an 8-bit signed two's complement integer. It has a minimum value of -128 and a maximum value of 127 (inclusive). The byte data type can be useful for saving memory in large arrays, where the memory savings actually matters. They can also be used in place of int where their limits help to clarify your code; the fact that a variable's range is limited can serve as a form of documentation.

它是如何节省内存的？什么是 2 的赞美？

Answer 1

它通过仅消耗 8 位存储空间来节省内存，而整数则为 32 位。数组的大小与包含的数据类型的大小成正比；整数数组消耗的内存 (handwaves) 是字节数组的四倍。

来自 Wikipedia :

A two's-complement system or two's-complement arithmetic is a system in which negative numbers are represented by the two's complement of the absolute value;1 this system is the most common method of representing signed integers on computers.[2] In such a system, a number is negated (converted from positive to negative or vice versa) by computing its two's complement. An N-bit two's-complement numeral system can represent every integer in the range −2^(N−1) to +2^(N−1)−1.