在Java中如何实现内部类封装与访问控制_OOP内部类访问方法分享

public class LinkedList {
    private Node head;

    // 私有内部类，封装节点结构
    private class Node {
        int data;
        Node next;

        Node(int data) {
            this.data = data;
        }
    }

    // 外部类提供公共方法操作内部类
    public void add(int data) {
        Node newNode = new Node(data);
        if (head == null) {
            head = newNode;
        } else {
            Node current = head;
            while (current.next != null) {
                current = current.next;
            }
            current.next = newNode;
        }
    }
}

public void process() {
    final int threshold = 10;

    class DataProcessor {
        void filter(int[] values) {
            for (int v : values) {
                if (v > threshold) {  // 可访问外部方法的 final 变量
                    System.out.println(v);
                }
            }
        }
    }

    new DataProcessor().filter(new int[]{5, 12, 8, 15});
}

public class Computer {
    private String cpu;
    private String ram;

    private Computer(Builder builder) {
        this.cpu = builder.cpu;
        this.ram = builder.ram;
    }

    // 静态内部类作为构建器
    public static class Builder {
        private String cpu;
        private String ram;

        public Builder setCpu(String cpu) {
            this.cpu = cpu;
            return this;
        }

        public Builder setRam(String ram) {
            this.ram = ram;
            return this;
        }

        public Computer build() {
            return new Computer(this);
        }
    }
}

new Thread(new Runnable() {
    @Override
    public void run() {
        System.out.println("运行在内部类线程中");
    }
}).start();