抽象工厂模式

抽象工厂模式（Abstract Factory），提供一个创建一系列相关或相互依赖对象的接口，而无需指定它们具体的类。

结构图：

 代码如下：

public class AbstractFactoryTest {
    public static void main(String[] args) {
        User user = new User();
        Department department = new Department();
        
        IUser iuser = DataAccess.createUser(); //直接得到数据访问实力，而不存在任何依赖
        iuser.insertUser(user);
        iuser.getUser("id");
        
        IDepartment idepartment = DataAccess.createDepartment();
        idepartment.insertDepartment(department);
        idepartment.getDepartment("id");
    }

}

package com.cai.designMethods.abstractFactory;

public class DataAccess {
    private static final String bd = "Sqlserver"; //数据库名 可换成Access
    
    public static IUser createUser(){
        IUser user = null;
        if("Sqlserver".equals(bd)){
            user = new SqlserverUser();
        }else if("Access".equals(bd)){
            user = new AccessUser();
        }
        return user;
    }
    
    public static IDepartment createDepartment(){
        IDepartment departmrnt = null;
        if("Sqlserver".equals(bd)){
            departmrnt = new SqlserverDepartment();
        }else if("Access".equals(bd)){
            departmrnt = new AccessDepartment();
        }
        return departmrnt;
    }
        
}

public interface IUser {
    int insertUser(User user);
    User getUser(String id);

}

public class AccessUser implements IUser {

    @Override
    public int insertUser(User user) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public User getUser(String id) {
        // TODO Auto-generated method stub
        return null;
    }

}

public class SqlserverUser implements IUser {

    @Override
    public int insertUser(User user) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public User getUser(String id) {
        // TODO Auto-generated method stub
        return null;
    }

}

public interface IDepartment {
    int insertDepartment(Department department);
    User getDepartment(String id);
}

public class AccessDepartment implements IDepartment {

    @Override
    public int insertDepartment(Department department) {
        return 0;
    }

    @Override
    public User getDepartment(String id) {
        return null;
    }

}

public class SqlserverDepartment implements IDepartment {

    @Override
    public int insertDepartment(Department department) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public User getDepartment(String id) {
        // TODO Auto-generated method stub
        return null;
    }

}

public class User {

}

public class Department {

}