Mybatis-plus自动填充starter

Mybatis-plus自动填充starter

前言：

上一篇我们说了自动填充，现在利用spring-boot把它抽象为一个组件，可以在项目中共同使用

工具

• IDEA 2021.1.1
• MAVEN 3.6.3
• JDK1.8
• spring-boot 2.1.3.RELEASE

配置

一、引入依赖

<!-- mybatis-plus start 勿需再引入mybatis依赖了 -->
    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>mybatis-plus-boot-starter</artifactId>
        <version>3.4.0</version>
    </dependency>
<!-- 配置提示 可有可无 -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-configuration-processor</artifactId>
        <optional>true</optional>
    </dependency>

二、配置自动填充的字段与启用

package com.ypshengxian.mybatisplus.properties;

import lombok.Getter;
import lombok.Setter;
import org.springframework.boot.context.properties.ConfigurationProperties;

/**
 * 描述：自动填充配置
 * Created on 2021/7/15 09:34
 * @author zjw
 */
@Setter
@Getter
@ConfigurationProperties(prefix = "ypsx.mybatis-plus.auto-fill")
public class MybatisPlusAutoFillProperties {
    /**
     * 是否开启自动填充字段
     */
    private Boolean enabled = true;
    /**
     * 是否开启了插入填充
     */
    private Boolean enableInsertFill = true;
    /**
     * 是否开启了更新填充
     */
    private Boolean enableUpdateFill = true;
    /**
     * 创建时间字段名
     */
    private String createTimeField = "gmtCreate";
    /**
     * 更新时间字段名
     */
    private String updateTimeField = "gmtModified";
}

三、实现元对象处理器接口：MetaObjectHandler

• 实现元对象处理器接口：com.baomidou.mybatisplus.core.handlers.MetaObjectHandler

package com.ypshengxian.mybatisplus.config;

import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
import com.ypshengxian.mybatisplus.properties.MybatisPlusAutoFillProperties;
import org.apache.ibatis.reflection.MetaObject;

import java.util.Date;

/**
 * 描述：自动填充
 * Created on 2021/7/14 18:58
 * @author zjw
 */
public class MyMetaObjectHandler implements MetaObjectHandler {
    private final MybatisPlusAutoFillProperties autoFillProperties;

    public MyMetaObjectHandler(MybatisPlusAutoFillProperties autoFillProperties) {
        this.autoFillProperties = autoFillProperties;
    }

    /**
     * 是否开启了插入填充
     */
    @Override
    public boolean openInsertFill() {
        return autoFillProperties.getEnableInsertFill();
    }

    /**
     * 是否开启了更新填充
     */
    @Override
    public boolean openUpdateFill() {
        return autoFillProperties.getEnableUpdateFill();
    }

    /**
     * 插入填充，字段为空自动填充
     */
    @Override
    public void insertFill(MetaObject metaObject) {
        Object createTime = getFieldValByName(autoFillProperties.getCreateTimeField(), metaObject);
        Object updateTime = getFieldValByName(autoFillProperties.getUpdateTimeField(), metaObject);
        if (createTime == null || updateTime == null) {
            Date date = new Date();
            if (createTime == null) {
                setFieldValByName(autoFillProperties.getCreateTimeField(), date, metaObject);
            }
            if (updateTime == null) {
                setFieldValByName(autoFillProperties.getUpdateTimeField(), date, metaObject);
            }
        }
    }

    /**
     * 更新填充
     */
    @Override
    public void updateFill(MetaObject metaObject) {
        setFieldValByName(autoFillProperties.getUpdateTimeField(), new Date(), metaObject);
    }
    // // TODO: 2021/7/14 测试？
    // @Override
    // public void insertFill(MetaObject metaObject) {
    //     this.strictInsertFill(metaObject, "gmtCreate", Date.class, new Date()); // 起始版本 3.3.0(推荐使用)
    //     this.strictInsertFill(metaObject, "gmtModified", Date.class, new Date()); // 起始版本 3.3.0(推荐使用)
    // }
    //
    // @Override
    // public void updateFill(MetaObject metaObject) {
    //     this.strictUpdateFill(metaObject, "gmtModified", Date.class, new Date()); // 起始版本 3.3.0(推荐)
    // }
}

四、配置AutoConfigure注入 MetaObjectHandler Bean

package com.ypshengxian.mybatisplus.config;

import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
import com.ypshengxian.mybatisplus.properties.MybatisPlusAutoFillProperties;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;

/**
 * 描述：mybatis-plus配置
 * Created on 2021/7/15 09:37
 * @author zjw
 */
@EnableConfigurationProperties(MybatisPlusAutoFillProperties.class)
public class MybatisPlusAutoConfigure {

    @Autowired
    private MybatisPlusAutoFillProperties autoFillProperties;


    @Bean
    @ConditionalOnMissingBean
    @ConditionalOnProperty(prefix = "ypsx.mybatis-plus.auto-fill", name = "enabled", havingValue = "true", matchIfMissing = true)
    public MetaObjectHandler metaObjectHandler() {
        return new MyMetaObjectHandler(autoFillProperties);
    }
}

五、默认生效

resources资源文件夹下新建META-INF/spring.factories，内容如下

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.ypshengxian.mybatisplus.config.MybatisPlusAutoConfigure