JAVA 2021:  
  


      ,    Java,   ,     .           ,               .              Java,         .





JAVA 2021:  



  


   



  ,2020



ISBN978-5-0051-5483-5

     Ridero








   蠖  ,   Java,   ,    .      15,      Java  ࠖ    .      젖   ,           .        :  Skillbox, Udemy, Stepik,   .    -    ,     :         ,       .             Java,      .




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 Java?


      .      TIOBE (https://www.tiobe.com/tiobe-index/ (https://www.tiobe.com/tiobe-index/)):








Ƞ  ,    : Java, C, Python, C++, C#.      ,    .      -10,          .

  ,   ,  10+     ,   Ruby.   , ,       .    ,     - .

10-  Swift.  Apple,  ObjectiveC   MacOS\iOS (  Kotlin,  Java Android).         Apple,         .         . ʠ,       .

9-  SQL.    ,       ,           .       .

8- PHP.      ,       . 80%   PHP.    젖 PHP       (    ,    ). PHP   ,       ,     -. ..  :    ,      1.

7-  JavaScript.      ,  ,      (      ).       .     :       ,              堖    iOS, MacOS, Android, Windows ( Electron),   ( NodeJS).     ,   :     ,   (  ,         )   䠖   !   ,     20   JavaScript.

6- VisualBasic.NET.  :     -10,    .   ,        MS Office,             .

5-  C#.     ()  Microsoft. NET.  ,    ,     Microsoft.      ,   :     ,   Windows    . NET  Java,    ( ). Ѡ        Xamarin,    .     Unity,   C#,       . C#    , ..  Windows.       ,    ,      C#     .

4-  C++.       .     .   ,     : ,  , .    C++,   -    .   :     (-   , , Brainfuck)        ,        .

3-  Python.       . ,   λ:     (Flask\Django),       , big data,        .  ,           ,      (   C   ).

2-  C.    , ,     C++.   C++,     .

1-  Java.   :).       .    Java       ,   :  Java?    ,   ,        .  ,  Java    ,    ( C#   ,   ),         :  ,    . Java   ,  Yandex Google.   ,     . Ѡ    Java  ,       .     ,     . Java      Android,       iOS (Objective C). Ƞ :     ,     - ,    .         (   )   Java.   Java  ,                ,    Java. Ƞ     Yandex   ,      ,   




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            . Ƞ    ,    .   21          -:     ,     .  2020   堖         .          ,   -  -10.

Swift.      iPhone\iPad.       .      - Objective C,   Swift    ,     .

PHP.      ,   .      WordPress\Drupal\Joomla    .    ,          PHP (.. , , ,    ),      .    ( )  HTML, CSS, JavaScript     .

JavaScript.    . ,  :    HTML, CSS   , -,  SPA (single-page application).  :     JavaScript     NodeJS    ,     ,    C++/C#/Java.  :    HTML, CSS    Adobe Flash (      )  ,  .      ( ):    HTML CSS JavaScript,     ReactJS !  -,   ,    (  !    IT  頖     ).

C#.         Windows. C 99%      ASP.NET  ,     HTML, CSS JavaScript ( ).  :   Unity.  :  -    , ,    Skype.

++\.    .   : ,  ,    ,   .

Python.   :      ,         蠖  HTML, CSS, JavaScript.  ,    ,     .  :  ,  .

Java.       ,          .     Android . Ƞ     : ,   , .




 


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    400500 8001000 ;

렖  15003000 ;

   300050006000 .

 ,    .  Java ,     800,  JavaScript ,   7000.  -,   10  .  PHP ,    WordPress  2000000.         ,  ,  蠖    .   ,    ,      +\    .

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 1.  

  



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 Java   :

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    Java.

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  ,    ,        Java     Java SDK.      IntelliJ IDEA,         .

 https://www.jetbrains.com/idea/download/ (https://ridero.ru/link/yoOtCjKGYlq_bA)






   : Ultimate (.. , ,    )  Community (    )



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    IntelliJ IDEA. Ƞ       (   ):






  













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Ƞ  ,    Create New Project.






    Java,   Project SDK: 11(  Java,   IntelliJ IDEA),  Next.






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  Project name HelloWorld(   ) Finish.



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IDEA      ,      ,      Tip ofthe Day     Close.








       ,  :



// write your code here.


:



System.out.println (Hello world!);









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    ,   IDEA:



Hello world!









,   : Process finished with exit code 0, ,     -  .  ,         !

  -   IntelliJ IDEA     .      :  Google\Yandex   IntelliJ IDEA,  Hello world IntelliJ IDEA          ,    ,   .       YouTube 2020       .

  ,     ,        .




 2. 



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       . ,  ,       77,      short,    .   頖    .  Java  8  :

boolean    ;

byte    ,    -128127;

short    ,    -3276832767;

int    ,    -21474836482147483647;

long    ,     9223372036854775808(-2 63) 9223372036854775807(2 63 1) ;

float    ,     1.410


3.410


;

double    ,     4.910


1.710


;

char  16 (2),   UTF.

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     :

int box1;

int box2 =70;

box1 =50;

int box3 = box1 + box2;

System.out.println (box3);

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      box1 box2    box3  int.

     (     )   box3 (120).




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   .

   ,     (https://www.litres.ru/book/pavel-aleksandrovich-zabelin/java-2021-legkiy-start-60973108/)  .

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