Java Basic data types

Java basic data types are numeric (int, byte, short, float, double) char (character char can only represent a single character such as a single letter A or a single character, such as Char c= ' a ' char c= ' I '), Boolean type ( True/false). It is important to note that string strings are a class in Java, not a data type. Decimals in Java are the default type of double. For example, when you want to define a decimal of float, float=2.5 is not compiled in this case, because the default decimal for Java is double,double with a precision higher than float. This is the equivalent of a double high-precision type of data, to a low-precision type processing. So if you want to define the data for float, you need to define that. Float a=2.4f The conversion of the data type, how to convert a high-precision value into a low-precision value. For example, the data of a float type is converted to the data of int: Cast int a = (int) 2.5; When converting high precision to low precision (float-to-int), the data of the fractional part is discarded directly, leaving only the integer part. Conversions in the calculation process the following example is a direct error and cannot be compiled. The reason is that a is a int,3.5 is a double type. This is done by adding an int and a double type of data, and then handing the data type B of an int to the loss of precision that cannot be compiled. When an integer and a high-precision numerical value are calculated, the result of the calculation will go to the high-precision int a=3;int b=a+3.5;

Java Basic data types