编译逻辑

:material-circle-edit-outline: 约 156 个字 :fontawesome-solid-code: 13 行代码 :material-clock-time-two-outline: 预计阅读时间 1 分钟

编译运行

javac Hello.java：编译

java Hello：编译完运行

结构

public class Hello{
    public static void main(String[] args){
        System.out.println("Hello, World!");
    }
}

• The basic unit of a Java program is a class.
  • A class called "Hello" is defined.
  • The name of the source file must be the same as the name of the class with a mandatory file extension of ".java".
    • Hence, this file MUST be saved as "Hello.java" - case-sensitive.
• public static void defines the so-called main() method, which is the entry point for program execution.

流程图

Writing a Java program:

• Step 1: Write the source code "Xxx.java".
• Step 2: Compile the source code "Xxx.java" into Java portable bytecode (or machine code) "Xxx.class" using the JDK's Java compiler by issuing the command "javac Xxx.java".
• Step 3: Run the compiled bytecode "Xxx.class", using the JDK's Java Runtime by issuing the command "java Xxx".

Other

Whitespaces: Blank, tab, and newline are collectively called whitespace.

Template

/*
 * Comment to state the purpose of the program
 */
public class Classname {   // Choose a meaningful Classname. Save as "Classname.java"
   public static void main(String[] args) {  // Entry point of the program
      // Your programming statements here!!!
   }
}