使用MapStruct实现DTO、VO等之间的转换

1、添加依赖

2、三种场景(对象之间转换，list之间转换、多个对象转为一个对象)

一、依赖

        
            org.mapstruct
            mapstruct-jdk8
            1.2.0.Final
        
        
            org.mapstruct
            mapstruct-processor
            1.2.0.Final
        

二、三种场景

import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.Mappings;
import org.mapstruct.factory.Mappers;

import java.util.List;

@Mapper
public interface UserAssemble {
    UserAssemble INSTANCE = Mappers.getMapper(UserAssemble.class);

    
    @Mappings({
            @Mapping(source = "id", target = "id", defaultValue = "000000"),
            @Mapping(source = "username", target = "username")
    })
    UserDTO entityToUserDTO(User user);

    
    List entityListToUserDTOList(List user);

    
    @Mappings({
            @Mapping(source = "user.id", target = "id"),
            @Mapping(source = "address.city", target = "address")
    })
    UserDTO EntityAndAddressToUserDTO(User user, Address address);
}

三、测试

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

public class Test {
    public static void main(String[] args) {
        UserAssemble instance = UserAssemble.INSTANCE;
        User user = new User();
        user.setId(111111L);
        user.setUsername("999999");
        List users = new ArrayList<>();
        users.add(user);
        Address address = new Address();
        address.setCity("南京");

        // 1、entity转换为dto
        UserDTO userDTO = instance.entityToUserDTO(user);
        System.out.println(userDTO.toString());

        // 2、entityList转换为DTOList
        List userDTOS = instance.entityListToUserDTOList(users);
        System.out.println(userDTOS.toString());

        // 3、多个对象转换到一个对象
        UserDTO userDTO1 = instance.EntityAndAddressToUserDTO(user, address);
        System.out.println(userDTO1);
    }
}

四、其它代码如下

public class User {
    private String username;
    private Long id;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }
}

public class Address {
    private String province;

    private String city;

    public String getProvince() {
        return province;
    }

    public void setProvince(String province) {
        this.province = province;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    @Override
    public String toString() {
        return "Address{" +
                "province='" + province + ''' +
                ", city='" + city + ''' +
                '}';
    }
}

public class UserDTO {
    private String username;
    private String id;
    private String address;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String other) {
        this.address = other;
    }

    @Override
    public String toString() {
        return "UserDTO{" +
                "username='" + username + ''' +
                ", id='" + id + ''' +
                ", other='" + address + ''' +
                '}';
    }
}