Basic data types for learning notes-conversion between wrapper class-string

Basic type wrapper class String class

Int->integer:integer Constructors

Integer-> Int:Integer.intValue () method

INT---String:Integer.toString method, String.valueof () method

String--Int:Integer.parseInt () method

Integer--String:Integer.toString () method, String.valueof () method

Constructor, Integer.valueof () method, String--Integer:integer

Auto-Unboxing after 5.0

For example:

Integer iobj1 = 10; Mount

int j = iobj1; Split

 Public classTestdemo { Public Static voidIntdemo () {//int->string//String-int        intA = 3;        System.out.println (a); String A1=integer.tostring (a);        SYSTEM.OUT.PRINTLN (A1); intA2 =Integer.parseint (A1); SYSTEM.OUT.PRINTLN (A2+ R); //int, Integer//Integer-intInteger A3 =A; inta4 =A3.intvalue ();        SYSTEM.OUT.PRINTLN (A3);        System.out.println (A4); //String, Integer//String-IntegerInteger i =NewInteger (10); String A5=i.tostring ();        System.out.println (A5); Integer I2=Integer.valueof (A5); Integer i3=Integer.parseint (A5); System.out.println (I2+ 5); SYSTEM.OUT.PRINTLN (i3+ 7); }         Public Static voidFloatdemo () {//float->float//float->float        floatF1 = 1.20f; Float F2=F1; floatF3 =F2; SYSTEM.OUT.PRINTLN (F2+ "\ T" +F3); //String, float//float, String        floatF4 = 2.234f; String f5=float.tostring (F4); System.out.println (F5+ 7); F4=float.parsefloat (F5);                SYSTEM.OUT.PRINTLN (F4); //String, Float//Float, StringFloat F6 =NewFloat (12.4); String F7=float.tostring (f6); System.out.println (F7+ 9); F6=float.parsefloat (F7); System.out.println (f6+ 1.1f); }         Public Static voidChardemo () {//Char-Character//Character-Char        Charch = ' P '; Character CH2=NewCharacter (' Q ')); CH2=ch;        System.out.println (CH2); CH=NewCharacter (' u ');                SYSTEM.OUT.PRINTLN (CH); //Char-String//String-Char        CharCH3 = ' Q '; String CH4=character.tostring (CH3);        SYSTEM.OUT.PRINTLN (CH4); CharCH5 = Ch4.charat (0);                System.out.println (CH5); //Character, String//String --CharacterCharacter Ch6 =NewCharacter (' a '); String Ch7= Ch6 + "";        System.out.println (CH7); Character Ch8=character.valueof (CH6);    System.out.println (CH8); }         Public Static voidMain (string[] args) {Testdemo.intdemo (); }}

Basic data types for learning notes-conversion between wrapper class-string