11.5

[实验任务一]：组合模式

用透明组合模式实现教材中的“文件夹浏览”这个例子。

package Tutorial10;

abstract  class FileSystemComponent {
    public void add(FileSystemComponent component) {
        throw new UnsupportedOperationException();
    }

    public void remove(FileSystemComponent component) {
        throw new UnsupportedOperationException();
    }

    public FileSystemComponent getChild(int index) {
        throw new UnsupportedOperationException();
    }

    public abstract void execute();  // 执行方法，打印提示信息
}

package Tutorial10;
public class File extends FileSystemComponent{
    private String name;
    public File(String name) {
        this.name = name;
    }
    @Override
    public void execute() {
        System.out.println("执行文件：" + name);  // 模拟文件的执行
    }
}

package Tutorial10;
import java.util.ArrayList;
import java.util.List;

public class Folder extends FileSystemComponent{
    private String name;
    private List<FileSystemComponent> components = new ArrayList<>();

    public Folder(String name) {
        this.name = name;
    }
    @Override
    public void add(FileSystemComponent component) {
        components.add(component);
    }
    @Override
    public void remove(FileSystemComponent component) {
        components.remove(component);
    }
    @Override
    public FileSystemComponent getChild(int index) {
        return components.get(index);
    }
    @Override
    public void execute() {
        System.out.println("执行文件夹：" + name);
        for (FileSystemComponent component : components) {
            component.execute();  // 执行文件夹中的每个文件或子文件夹
        }
    }
}

package Tutorial10;

public class FileSystemTest {
    public static void main(String[] args) {
        // 创建文件
        File file1 = new File("文件1.txt");
        File file2 = new File("文件2.txt");

        // 创建文件夹
        Folder folder1 = new Folder("文件夹1");
        Folder folder2 = new Folder("文件夹2");

        // 将文件添加到文件夹
        folder1.add(file1);
        folder1.add(file2);

        // 将文件夹添加到另一个文件夹
        folder2.add(folder1);

        // 执行文件夹操作，展示透明组合模式
        folder2.execute();  // 执行文件夹2，里面包含文件夹1，文件夹1又包含文件
    }
}