DDD模型分层设计—随记（250611）

原创已于 2025-06-11 22:18:06 修改 · 121 阅读

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#java

于 2025-06-11 21:57:44 首次发布

UML类图

在这里插入图片描述

model层

BaseModel

/**
 * 基础类
 */
public abstract class BaseModel<T extends BaseModel<T>> {
    private final Map<Class<? extends T>, T> extObjCache = new ConcurrentHashMap<>();

    public <E extends T> E getExtObj(Class<E> extClass) {
        if (!this.getClass().isAssignableFrom(extClass)) {
            throw new IllegalArgumentException(
                    extClass.getSimpleName() + " must extend " + this.getClass().getSimpleName()
            );
        }

        return extClass.cast(
                extObjCache.computeIfAbsent(extClass, k -> {
                    try {
                        E extObj = extClass.getDeclaredConstructor().newInstance();
                        BeanUtil.copyProperties(this, extObj);
                        return extObj;
                    } catch (Exception e) {
                        throw new RuntimeException("Failed to create extension object", e);
                    }
                })
        );
    }
}

Model

/**
 * 模型类
 */
@Getter
@Setter
public class Model extends BaseModel<Model> {
    private String name;
}

SubModel

/**
 * 子模型
 */
@Getter
@Setter
public class SubModel extends BaseModel<SubModel> {
    private String name;
}

domain层

ModelExt

/**
 * 拓展类
 */
public class ModelExt extends Model {
    private List<SubModel> subModelList;

    public List<SubModel> querySubModelList() {
        // SubModelService service = SpringUtils.getBean(SubModelService.class);
        List<SubModel> subModels = new ArrayList<>();
        SubModel subModel = new SubModel();
        subModel.setName("subModel");
        subModels.add(subModel);
        return subModels;
    }
}

测试

public class MainTest {
    public static void main(String[] args) {
        Model model = new Model();
        model.setName("model");

        ModelExt extObj = model.getExtObj(ModelExt.class);
        System.out.println(extObj);
        ModelExt extObj1 = model.getExtObj(ModelExt.class);
        System.out.println(extObj1);

        List<SubModel> subModelList = model.getExtObj(ModelExt.class).querySubModelList();
        subModelList.forEach(v-> System.out.println(v.getName()));
    }
}