MyBatis resultMap與POJO中的構建器

Question

假設我有一個Java類，代表使用構建器模式的Person：

package com.xyz.domain;

public class Person {

    private final int id;
    private final String firstName;
    private final String middleName;
    private final String lastName;
    private final String address;
    private final String country;

    private Person(PersonBuilder builder) {
        this.id = id;
        this.firstName = builder.firstName;
        this.middleName = builder.middleName;
        this.lastName = builder.lastName;
        this.address = builder.address;
        this.country = builder.country;
    }

    // getters go here

    public static class PersonBuilder {

        private int id;
        private final String firstName;
        private final String lastName;

        private String middleName;
        private String address;
        private String country;

        public PersonBuilder(int id, String firstName, String lastName) {
            this.id = id;
            this.firstName = firstName;
            this.lastName = lastName;
        }

        public PersonBuilder withMiddleName(String middleName) {
            this.middleName = middleName;
            return this;
        }

        public PersonBuilder withAddress(String address) {
            this.address = address;
            return this;
        }

        public PersonBuilder withCountry(String country) {
            this.country = country;
            return this;
        }

        public Person build() {
            return new Person(this);
        }
    }
}

我想以此作為mybatis resultMap的type ，如下所示：

<resultMap id="Person" type="com.xyz.domain.Person">
    <id property="id" column="id" />
    <result property="firstName" column="first_name" />
    <result property="middleName" column="middle_name" />
    <result property="lastName" column="last_name" />
    <result property="address" column="address" />
    <result property="country" column="country" />
</resultMap>

但是，當我調用使用此結果映射的端點時，這會在Spring應用程序中產生500錯誤。 我也嘗試過將resultMap的type參數設置為com.xyz.domain.Person.PersonBuilder並得到一個錯誤。 有什么辦法可以在不犧牲Person類中的構建器模式的情況下進行此工作？

Answer 1

用@Alias（“ Person”）批注標記POJO。 還要確保在配置myBatis數據連接時，包含了com.xyz.domain軟件包來掃描POJO。

Answer 2

我可以通過更新結果圖來解決此問題

<resultMap id="Person" type="com.xyz.domain.Person$PersonBuilder">
    <constructor>
        <idArg name="id" column="id" />
        <arg name="firstName" column="first_name" />
        <arg name="lastName" column="last_name" />
    </constructor>
    <result property="middleName" column="middle_name" />
    <result property="address" column="address" />
    <result property="country" column="country" />
</resultMap>

這將創建一個PersonBuilder對象列表，但是很容易遍歷該列表並在java中的每個列表項上調用build()方法： personBuilderList.stream().map(Person.PersonBuilder::build).collect(toList())