JavaSE ---- 03. Data Types

03. Data Types

1, the data type classification

    Java is a strongly typed language, Java data types are divided into two categories, namely, basic data types and reference data types . Wherein the basic data types defined in the Java language, which is a fixed size of memory occupied by the data, stored in memory is the value of the value itself ; and the reference data type is stored in memory storage address of reference data , the data is not itself.

Java's two data types:

基本数据类型:整型类型、浮点类型、字符类型、布尔类型

引用数据类型:类、接口、数组

2, integer

    Declared as constant or variable integer type is used to store an integer. Including byte integer type (byte), short integer (Short), integer (int), long integer (long) 4 data types, different number of bytes in the memory are occupied.