Shulou(Shulou.com)06/02 Report--

This article introduces the relevant knowledge of "what skills should be mastered in Zero basic Java". In the operation of actual cases, many people will encounter such a dilemma, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

It is also essential for beginners to understand these basic concepts of Java, and it is certainly not possible to memorize them by rote, focusing on understanding, understanding the differences and connections between them, and what applications they have. Think about what knowledge points are used in this code. Don't just hit the code according to the book. First understand what are the four aspects of Java.

The 1.Java programming language, or syntax.

2.Java file format, that is, the suffix of various folders and files.

The 3.Java virtual machine (JVM), which is the interpreter that processes * .class files.

4.Java Application Program Interface (Java API).

First, master static methods and properties

Static methods and properties are used to describe the characteristics of a group of objects, rather than the characteristics of a single object. Static methods and properties are widely used in Java, which is a common technique. But this technique is not frequently used in many languages.

Understanding static methods and attributes, which are frequently used in a large number of Java specifications, is very helpful in understanding the relationship between classes and objects. Therefore, learners should understand static methods and attributes. Java is consistent in the invocation of methods and properties, except when declared, which is different from C++.

II. The relationship between the three technology platforms of Java

Java is divided into three systems, namely Java SE (J2SE Java 2 Platform Standard Edition, Standard Edition). JavaEE (J2EE Java 2 Platform, Enterprise Edition, Enterprise Edition). Java ME (J2ME Java 2 Platform Micro Edition, miniature version).

You should know that Java is divided into two parts: one is to compile and the other is to run.

Javac: responsible for the compilation part. When Javac is executed, the compiler program for Java will be started. Compiles the .Java file with the specified extension. A bytecode file that can be recognized by jvm is generated. That is, the class file, that is, the running program of Java.

Java: the part responsible for running. Jvm will be started. Load the class libraries needed for the runtime and execute the class file. For a file to be executed, there must be a starting point for execution, which is the main function.

Master the basic format of Java code

1. Java comments are as comprehensive as possible.

Comments on methods should include detailed input parameters and result descriptions, and exceptions thrown should also be described in detail: comments on classes should include functional descriptions, authors, and modifiers of the class.

2. The same variable used many times had better be reduced to a constant.

Variables with the same value used in multiple places should be summarized as a constant as far as possible to facilitate future maintenance.

3. Execute method calls in loops as little as possible

Try to make fewer avoidable method calls in the loop, which can save the creation of the method stack. For example:

For (int iTuno Bandi)

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.