类加载与初始化顺序

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<span style="font-family: Arial, Helvetica, sans-serif; background-color: rgb(255, 255, 255);">1、自下而上加载类的编译代码</span>

运行java程序时，首先要找main（），于是启动加载器加载main对应类的编译代码，在加载过程中，若发现有基类，则加载基类，以此类推。也就是从基类向下加载

2、自上而下的初始化static

可以看作是类加载时进行的，static初始化顺序，就是类加载顺序

3、默认初始化：基本类型和对象类型

4、基类构造器

5、变量定义的顺序显式初始化

6、自身的构造器

7、例：

class Meal {Meal() { System.out.println("Meal()"); }static {System.out.println("Meal static");}}class Bread {Bread() { System.out.println("Bread()"); }}class Cheese {Cheese() { System.out.println("Cheese()"); }static {System.out.println("Cheese static");}}class Lettuce {Lettuce() { System.out.println("Lettuce()"); }}class Lunch extends Meal {Lunch() { System.out.println("Lunch()"); }static {System.out.println("Lunch static");}}class PortableLunch extends Lunch {PortableLunch() { System.out.println("PortableLunch()"); }static {System.out.println("PortableLunch static");}}public class Sandwich extends PortableLunch {private Bread b = new Bread();private Cheese c = new Cheese();public Sandwich() { System.out.println("Sandwich()"); }private Lettuce l = new Lettuce();static {System.out.println("Sandwich static");}public static void main(String[] args) {// TODO Auto-generated method stubnew Sandwich();}}

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