Java overview

Java overview

1. Introduction To Computer Programming Languages

    1st generation language: Machine language (The instruction is implemented in the form of binary code).

    2nd generation language: Assembly language (Use mnemonics to indicate machine instructions).

    3rd generation language: High-level programming language:

        Object-oriented: C, Pascal, etc.;

        Process-oriented: Java, Python, etc.

2. Java Overview

    2.1 A Brief History of Java

        In 1995, it was released by SUN;

        In 2004, the JDK1.5 version was released and renamed to JDK5.0;

        In 2009, it was acquired by Oracle;

        In 2014, the JDK8.0 version was released.

    2.2 Characteristics of Java

        2.2.1 Object-oriented

            ① Two basic concepts: class and object;

            ② Three characteristics: encapsulation, inheritance and polymorphism.

        2.2.2 Robustness

            Pointers and garbage collection.

        2.2.3 Cross-platform

            Java can run on different system platforms.

    2.3 Java's core mechanism

            Java Virtal Machine (JVM) and Garbags Collection (GC).

3. Commonly Used Java Development Tools

    3.1 Text Editing Tool

        Txt, EditPlus, TextPad, NotePad, etc.

    3.2 Integrated Development Environment

        Eclipse, Netbeans, MyEclipse, etc.

 

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