Acquaintance eight basic data types of object-oriented wrapper class --Java base (25)

First, the sum

*     Eight basic data types of packaging: the basic data types encapsulation class (reference type)
  *     basic data types packaging
  *     byte          -   Byte
  *     Short         -   Short
  *     int           -   Integer
  *     Long          -   Long
  *     a float         -   Float
  *     Double        -   Double
  *     char          -   Character
  *     boolean       - Boolean

Second, the simple use of Integer

1. Comparison packaging type basic data type ==

 

 2. Create the way

        Integer integer1=1;
        Integer integer2=new Integer(1);

3. Conversion Value

        Integer1 Integer;
         int A =. 1 ; 
        String STR = ". 1" ; 

        // int converted to Integer 
        Integer1 = A; 

        // Integer to convert int 
        A = integer1.intValue (); 
        A = Integer1; // to assign int Integer type the words, JRE can do this yourself. 

        // String turn Integer 
        Integer1 = Integer.valueOf (str); 

        // Integer switch String 
        str = integer1.toString (); 

        // String -> int 
        a = Integer.valueOf ( STR) .intValue (); // Integer.valueOf (STR) is the return value of type Integer. 
        a = the Integer.parseInt (STR);// Integer.parseInt (str) return value is an int