Notes

package compositepattern;

import java.util.ArrayList;
import java.util.List;

interface FileSystemComponent {
public void displayDetails();
}

class File implements FileSystemComponent{

private String name;

public File(String name){
this.name = name;
}

@Override
public void displayDetails() {
System.out.println("File : " + name);
}
}

class Directory implements FileSystemComponent{

private String name;
private List<FileSystemComponent> children;

public Directory(String name){
this.name = name;
children = new ArrayList<>();
}

public void addComponent(FileSystemComponent component) {
children.add(component);
}

public void removeComponent(FileSystemComponent component) {
children.remove(component);
}

@Override
public void displayDetails() {
System.out.println("Directory: " + name);
System.out.println("Contents:");
for (FileSystemComponent component : children) {
component.displayDetails();
}
}

}

public class CompositePatternDemo {
public static void main(String[] args) {
File file1 = new File("Document.txt");
File file2 = new File("Image.jpg");
File file3 = new File("Spreadsheet.xlsx");

Directory directory1 = new Directory("Documents");
directory1.addComponent(file1);
directory1.addComponent(file3);

Directory directory2 = new Directory("Pictures");
directory2.addComponent(file2);

Directory rootDirectory = new Directory("Root");
rootDirectory.addComponent(directory1);
rootDirectory.addComponent(directory2);

rootDirectory.displayDetails();
}
}