Static的静态常量访问与静态方法调用
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Static的静态方法调用
package com.tea.Demo07;
public class Student {
public void run(){ //非静态方法
}
public static void go(){ //静态方法
}
public static void main(String[] args) {
Student s1 = new Student();
Student.go(); //静态方法时，直接用类名调用
//Student.run(); //会报错，因为run()为非静态方法
//也可以用具体对象调用
s1.run();
s1.go();
}
}
Static的静态常量访问
package com.tea.Demo07;
public class Student {
private static int age; //静态常量
private double score; //非静态常量
public static void main(String[] args) {
Student s1 = new Student();
//还是建议常量为静态常量时，直接用类名访问
System.out.println(Student.age);
//System.out.println(Student.score);会报错，因为score为非静态常量
//也可以用具体对象访问
System.out.println(s1.age);
System.out.println(s1.score);
}
}
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static静态代码块
package com.tea.Demo07;
public class Person {
//2：赋初始值
{
//匿名代码块
System.out.println("匿名代码块");
}
//1:最先输出，而且只执行一次
static {
//静态代码块
System.out.println("静态代码块");
}
//3
public Person() {
System.out.println("构造方法");
}
public static void main(String[] args) {
Person person1 = new Person();
System.out.println("===================");
Person person2 = new Person();
}
}
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静态导入包
package com.tea.Demo07;
import static java.lang.Math.random; //静态导入包
import static java.lang.Math.PI; //静态导入包
public class Test {
public static void main(String[] args) {
System.out.println(random());
System.out.println(PI);
}
}
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标签：静态方法,常量,System,Static,Student,println,static,public,out From： https://www.cnblogs.com/bobocha/p/16747792.html