//外部类
public class testDeque {
int num=100;
//内部类
class A{
int num=10;
public void put(){
int num=1;
System.out.println("inner");
//num为方法中的 为了区分,使用 类名.this.变量名
System.out.println(num+" "+this.num+" "+testDeque.this.num);
}
public void put2(){
final int a=1;
// 局部内部类
class B{
public void put(){
// 只能使用方法final的变量,不能改变
System.out.println(a);
}
}
}
}
// Good接口
// public interface Good {
// int put(int a);
// }
public static void main(String[] args) {
//匿名内部类实现接口
Good good1 = new Good() {
@Override
public int put(int a) {
return a;
}
};
//lambda表达式简化匿名内部类 ()->{ }
Good good2=(int a)->{
return a; };
//lambda表达式单个参数简写方式
Good good=a->{
return a; };
//------------------------------------------------
//装箱
Integer integer1 = Integer.valueOf(1);
//自动装箱
Integer integer=1;
//拆箱
int a=integer.intValue();
//Integer转String
String s = integer.toString();
System.out.println(s+1);
//11
//转int
int aa=Integer.parseInt(s);
System.out.println(aa+1);
//2
}
}
From inner class to lambda expression + packaging class boxing and unboxing
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Origin blog.csdn.net/BOWWOB/article/details/113514796
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