Oracle Certification Associate 1Z0-808: Difference between revisions

From My Limbic Wiki
Line 58: Line 58:
'''It is not a good idea to do static imports a lot in a projet because it makes difficult to understand where the methods / constants come from'''
'''It is not a good idea to do static imports a lot in a projet because it makes difficult to understand where the methods / constants come from'''


'''Static imports''' are for '''importing static members'''
* '''Static imports''' are for '''importing static members'''
 
* '''Classic imports''' are for '''importing classes'''
'''Classic imports''' are for '''importing classes'''


it can be used for methods and constants for example
it can be used for methods and constants for example

Revision as of 16:48, 4 June 2020

Links

Installation

Windows

<source lang="Shell"> C:\Program Files\Java </source>

  • Java Se Development Kit 8
    • Java FX SDK
    • Private JRE - Java Runtime Edition
    • Java Mission Control Tools

Can also be installed:

    • Development Tools
    • Source Code
    • Public JRE

Linux

<source lang="Shell"> sudo apt-get install oracle-java8-installer cd /usr/lib/jvm/java-8-oracle

  1. Java version

java -v

  1. Java Compiler

javac -version </source>

Basics

Main Method

<source lang="Java"> public static void main(String[] args]) </source>

Comments

<source lang="Java"> // Single Line Comment

/* Multi Line Comment

  • /

/**

* Java Doc Comment
* @param
* @return 
*/

</source>

Import Conflicts

<source lang="Java"> import java.util.*; import java.sql.*;

// ==> in code = COMPILATION error Date date; </source>

Static Imports

It is not a good idea to do static imports a lot in a projet because it makes difficult to understand where the methods / constants come from

  • Static imports are for importing static members
  • Classic imports are for importing classes

it can be used for methods and constants for example <source lang="Java"> import static java.lang,Math.*;

// Instead of typing Math.min(1,2); we can just type min(1,2) // Because of the static import </source>