Java - introduction of Java

Compare Java with C++

Compare Java with Java Script

Analyze a class (Main.java)

package com.example;
public class Main() {
  public static void main(String[] args) {
    System.out.println("Hello World");
  }
}

Java Command

• java: runtime
• javac: compiler
• javadoc: docs builder
• jar: archive builder

javac Main.java --> generate Main.class

java Main ---> run Main.class --> output: Hello World

Identifier Conventions

• Class start with uppercase character: class MyClass
• Methods and variables start with lowercase character:void doSomething(String withThis) {}
• Constants are full uppercase:final String FIRSTNAME = "David";

Compare Java with C++

Compare Java with Java Script

Analyze a class (Main.java)

package com.example;
public class Main() {
  public static void main(String[] args) {
    System.out.println("Hello World");
  }
}

Java Command

• java: runtime
• javac: compiler
• javadoc: docs builder
• jar: archive builder

javac Main.java --> generate Main.class

java Main ---> run Main.class --> output: Hello World

Identifier Conventions

• Class start with uppercase character: class MyClass
• Methods and variables start with lowercase character:void doSomething(String withThis) {}
• Constants are full uppercase:final String FIRSTNAME = "David";

Compare Java with C++

Compare Java with Java Script

Analyze a class (Main.java)

package com.example;
public class Main() {
  public static void main(String[] args) {
    System.out.println("Hello World");
  }
}

Java Command

• java: runtime
• javac: compiler
• javadoc: docs builder
• jar: archive builder

javac Main.java --> generate Main.class

java Main ---> run Main.class --> output: Hello World

Identifier Conventions

• Class start with uppercase character: class MyClass
• Methods and variables start with lowercase character:void doSomething(String withThis) {}
• Constants are full uppercase:final String FIRSTNAME = "David";