局部内部类：局部内部类实在方法中定义的类，所以外界是无法直接使用的，需要在方法内部创建对象并使用该类，该类可以直接访问外部类成员

示例：

package leiqiantao;

public class Outer1 {
    private int num1=20;
    public void method(){
        int num2=10;
        class Inner1{
            public void show(){
                System.out.println(num1+","+num2);
            }
        }
        Inner1 i=new Inner1();
        i.show();
    }
}

package leiqiantao;

public class Outer1Demo {
    public static void main(String[] args) {
        Outer1 o=new Outer1();
        o.method();
    }
}

D:\Java\jdk-16.0.1\bin\java.exe -Didea.launcher.port=60353 "-Didea.launcher.bin.path=D:\IntelliJ IDEA 2018.2.8\bin" -Dfile.encoding=UTF-8 -classpath "C:\Users\dell\IdeaProjects\java学习\out\production\java学习;D:\IntelliJ IDEA 2018.2.8\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMainV2 leiqiantao.Outer1Demo

20,10

Process finished with exit code 0

匿名内部类：是局部内部类的一种。

前提：存在一个类或接口，这里的类可以是具体类也可以是抽象类

格式：

     New 类名或者接口名(){

      重写方法；

}；

匿名内部类的本质，是一个继承了该类或者实现了该接口的子类匿名对象。

示例：package leiqiantao;



public interface Show {

    void show();

}

package leiqiantao;

import javax.swing.*;

public class Outer2 {
    private String name="迷茫";
    public void method(){
        /*
        new Show(){
            public void show(){
                System.out.println();
            }
        };

        new Show(){
            public void show(){
                System.out.println();
            }
        }.show();
        */
        Show s=new Show(){
            public void show(){
                System.out.println(name);
            }
        };
        s.show();
        s.show();
    }
}

package leiqiantao;

public class Outer2Demo {
    public static void main(String[] args) {
        Outer2 o=new Outer2();
        o.method();
    }
}

D:\Java\jdk-16.0.1\bin\java.exe -Didea.launcher.port=58472 "-Didea.launcher.bin.path=D:\IntelliJ IDEA 2018.2.8\bin" -Dfile.encoding=UTF-8 -classpath "C:\Users\dell\IdeaProjects\java学习\out\production\java学习;D:\IntelliJ IDEA 2018.2.8\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMainV2 leiqiantao.Outer2Demo

迷茫

迷茫

Process finished with exit code 0

匿名内部类的应用：

package leiqiantao;

public interface Climb {
    void climb();
}

package leiqiantao;

public class ClimbOperator {
    public void method(Climb j){
            j.climb();
        }
}

package leiqiantao;

public class ClimbDemo {
    public static void main(String[] args) {
        ClimbOperator c=new ClimbOperator();
        c.method(new Climb() {
            @Override
            public void climb() {
                System.out.println("猴子可以爬树");
            }
        });
        c.method(new Climb() {
            @Override
            public void climb() {
                System.out.println("猪都可以上树");
            }
        });
    }
}

D:\Java\jdk-16.0.1\bin\java.exe -Didea.launcher.port=55171 "-Didea.launcher.bin.path=D:\IntelliJ IDEA 2018.2.8\bin" -Dfile.encoding=UTF-8 -classpath "C:\Users\dell\IdeaProjects\java学习\out\production\java学习;D:\IntelliJ IDEA 2018.2.8\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMainV2 leiqiantao.ClimbDemo

猴子可以爬树

猪都可以上树

Process finished with exit code 0