JAVA SE(1) Chapter One First Understanding of Java Java Architecture and Core Mechanism 2020-12-14

JAVASE(1)

Chapter 1: Getting to Know Java

table of Contents

Java architecture

Java core mechanism

Expansion-C language cross-platform principle

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Java architecture

• JavaSE (Java Standard Edition): Standard Edition, an application positioned on personal computers.
• JavaEE (Java Enterprise Edition): Enterprise Edition, a server-side application.
• JavaME (Java Micro Edition): Micro Edition, positioned in the application of consumer electronic products.
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Java core mechanism

• Garbage collection mechanism
• Cross-platform principle
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Expansion-C language cross-platform principle

    

• The difference between C language cross platform and Java cross platform:

    (1) Java bytecode file has nothing to do with the platform. Take this bytecode file to run on different platforms.

    (2) Different platforms of the C language have different compilers. The compiler is related to the platform, and the compiled executable file is also related to the platform.

• Is C language cross-platform?

      Answer: In fact, what we mean by cross-platform refers to whether the compiled file is cross-platform . From this perspective, the C language is not cross-platform.

             Many people on the Internet say that the C language is cross-platform because different platforms have different compilers. It refers to the cross-platform source files .

• Is C language efficient or Java efficient?

      Answer: C language is highly efficient . Because the executable file it produces can be run directly on the platform.