吴裕雄--天生自然 JAVA开发学习：变量类型

Posted 2021-12-14 tszr

public class Variable
    static int allClicks=0;    // 类变量
 
    String str="hello world";  // 实例变量
 
    public void method()
 
        int i =0;  // 局部变量
 
    

public class Test 
   public void pupAge()
      int age = 0;
      age = age + 7;
      System.out.println("小狗的年龄是: " + age);
   
   
   public static void main(String[] args)
      Test test = new Test();
      test.pupAge();
   

public class Test 
   public void pupAge()
      int age;
      age = age + 7;
      System.out.println("小狗的年龄是 : " + age);
   
   
   public static void main(String[] args)
      Test test = new Test();
      test.pupAge();
   

import java.io.*;
public class Employee
   // 这个实例变量对子类可见
   public String name;
   // 私有变量，仅在该类可见
   private double salary;
   //在构造器中对name赋值
   public Employee (String empName)
      name = empName;
   
   //设定salary的值
   public void setSalary(double empSal)
      salary = empSal;
     
   // 打印信息
   public void printEmp()
      System.out.println("名字 : " + name );
      System.out.println("薪水 : " + salary);
   
 
   public static void main(String[] args)
      Employee empOne = new Employee("RUNOOB");
      empOne.setSalary(1000);
      empOne.printEmp();
   

import java.io.*;
 
public class Employee 
    //salary是静态的私有变量
    private static double salary;
    // DEPARTMENT是一个常量
    public static final String DEPARTMENT = "开发人员";
    public static void main(String[] args)
    salary = 10000;
        System.out.println(DEPARTMENT+"平均工资:"+salary);