```
public class DefaultModule implements Module {

    private final String value;

    public DefaultModule(String value) {
        this.value = value;
    }

    @Override
    public void print() {
        System.out.println(value);
    }
}
```

```
public class ComponentModule implements Module {

    private final Module currentModule;

    private final List<Module> modules;

    public ComponentModule(Module currentModule, Module... modules) {
        this.currentModule = currentModule;
        this.modules = Arrays.asList(modules);
    }

    @Override
    public void print() {
        this.currentModule.print();
        this.modules.forEach(Module::print);
    }
}
```

```
public interface Module {

    void print();

    static void main(String[] args) {
        ComponentModule subModule31 = new ComponentModule(
            new DefaultModule("31"),
            new DefaultModule("311"),
            new DefaultModule("312"),
            new DefaultModule("313")
        );

        ComponentModule subModule3 = new ComponentModule(
            new DefaultModule("3"),
            subModule31,
            new DefaultModule("32"),
            new DefaultModule("33")
        );

        ComponentModule module = new ComponentModule(
            new DefaultModule("0"),
            new DefaultModule("1"),
            new DefaultModule("2"),
            subModule3
        );

        module.print();
    }
}
```

这样歪