阿里官宣：干掉Mybatis和MybatisPlus，推出新一代ORM框架FluentMybatis，太牛逼了！
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需求場景設(shè)置
create table `student_score`
(
id bigint auto_increment comment '主鍵ID' primary key,
student_id bigint not null comment '學(xué)號',
gender_man tinyint default 0 not null comment '性別, 0:女; 1:男',
school_term int null comment '學(xué)期',
subject varchar(30) null comment '學(xué)科',
score int null comment '成績',
gmt_create datetime not null comment '記錄創(chuàng)建時間',
gmt_modified datetime not null comment '記錄最后修改時間',
is_deleted tinyint default 0 not null comment '邏輯刪除標(biāo)識'
) engine = InnoDB default charset=utf8;
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select school_term,
subject,
count(score) as count,
min(score) as min_score,
max(score) as max_score,
avg(score) as max_score
from student_score
where school_term >= 2000
and subject in ('英語', '數(shù)學(xué)', '語文')
and score >= 60
and is_deleted = 0
group by school_term, subject
having count(score) > 1
order by school_term, subject;
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三者實(shí)現(xiàn)對比
使用fluent mybatis 來實(shí)現(xiàn)上面的功能
換成mybatis原生實(shí)現(xiàn)效果
定義Mapper接口
public interface MyStudentScoreMapper {
List<Map<String, Object>> summaryScore(SummaryQuery paras);
}
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定義接口需要用到的參數(shù)實(shí)體 SummaryQuery
@Data
@Accessors(chain = true)
public class SummaryQuery {
private Integer schoolTerm;
private List<String> subjects;
private Integer score;
private Integer minCount;
}
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定義實(shí)現(xiàn)業(yè)務(wù)邏輯的mapper xml文件
<select id="summaryScore" resultType="map" parameterType="cn.org.fluent.mybatis.springboot.demo.mapper.SummaryQuery">
select school_term,
subject,
count(score) as count,
min(score) as min_score,
max(score) as max_score,
avg(score) as max_score
from student_score
where school_term >= #{schoolTerm}
and subject in
<foreach collection="subjects" item="item" open="(" close=")" separator=",">
#{item}
</foreach>
and score >= #{score}
and is_deleted = 0
group by school_term, subject
having count(score) > #{minCount}
order by school_term, subject
</select>
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實(shí)現(xiàn)業(yè)務(wù)接口(這里是測試類, 實(shí)際應(yīng)用中應(yīng)該對應(yīng)Dao類)
@RunWith(SpringRunner.class)
@SpringBootTest(classes = QuickStartApplication.class)
public class MybatisDemo {
@Autowired
private MyStudentScoreMapper mapper;
@Test
public void mybatis_demo() {
// 構(gòu)造查詢參數(shù)
SummaryQuery paras = new SummaryQuery()
.setSchoolTerm(2000)
.setSubjects(Arrays.asList("英語", "數(shù)學(xué)", "語文"))
.setScore(60)
.setMinCount(1);
List<Map<String, Object>> summary = mapper.summaryScore(paras);
System.out.println(summary);
}
}
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換成mybatis plus實(shí)現(xiàn)效果
字段名稱的記憶和敲碼困難 Entity屬性跟隨數(shù)據(jù)庫字段發(fā)生變更后的運(yùn)行時錯誤
生成代碼編碼比較
fluent mybatis生成代碼設(shè)置
public class AppEntityGenerator {
static final String url = "jdbc:mysql://localhost:3306/fluent_mybatis_demo?useSSL=false&useUnicode=true&characterEncoding=utf-8";
public static void main(String[] args) {
FileGenerator.build(Abc.class);
}
@Tables(
/** 數(shù)據(jù)庫連接信息 **/
url = url, username = "root", password = "password",
/** Entity類parent package路徑 **/
basePack = "cn.org.fluent.mybatis.springboot.demo",
/** Entity代碼源目錄 **/
srcDir = "spring-boot-demo/src/main/java",
/** Dao代碼源目錄 **/
daoDir = "spring-boot-demo/src/main/java",
/** 如果表定義記錄創(chuàng)建，記錄修改，邏輯刪除字段 **/
gmtCreated = "gmt_create", gmtModified = "gmt_modified", logicDeleted = "is_deleted",
/** 需要生成文件的表 ( 表名稱:對應(yīng)的Entity名稱 ) **/
tables = @Table(value = {"student_score"})
)
static class Abc {
}
}
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mybatis plus代碼生成設(shè)置
public class CodeGenerator {
static String dbUrl = "jdbc:mysql://localhost:3306/fluent_mybatis_demo?useSSL=false&useUnicode=true&characterEncoding=utf-8";
@Test
public void generateCode() {
GlobalConfig config = new GlobalConfig();
DataSourceConfig dataSourceConfig = new DataSourceConfig();
dataSourceConfig.setDbType(DbType.MYSQL)
.setUrl(dbUrl)
.setUsername("root")
.setPassword("password")
.setDriverName(Driver.class.getName());
StrategyConfig strategyConfig = new StrategyConfig();
strategyConfig
.setCapitalMode(true)
.setEntityLombokModel(false)
.setNaming(NamingStrategy.underline_to_camel)
.setColumnNaming(NamingStrategy.underline_to_camel)
.setEntityTableFieldAnnotationEnable(true)
.setFieldPrefix(new String[]{"test_"})
.setInclude(new String[]{"student_score"})
.setLogicDeleteFieldName("is_deleted")
.setTableFillList(Arrays.asList(
new TableFill("gmt_create", FieldFill.INSERT),
new TableFill("gmt_modified", FieldFill.INSERT_UPDATE)));
config
.setActiveRecord(false)
.setIdType(IdType.AUTO)
.setOutputDir(System.getProperty("user.dir") + "/src/main/java/")
.setFileOverride(true);
new AutoGenerator().setGlobalConfig(config)
.setDataSource(dataSourceConfig)
.setStrategy(strategyConfig)
.setPackageInfo(
new PackageConfig()
.setParent("com.mp.demo")
.setController("controller")
.setEntity("entity")
).execute();
}
}
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FluentMybatis特性一覽
三者對比總結(jié)
| - | Mybatis Plus | Fluent Mybatis |
|---|---|---|
| 代碼生成 | 生成 Entity | 生成Entity, 再通過編譯生成 Mapper, Query, Update 和 SqlProvider |
| Generator易用性 | 低 | 高 |
| 和Mybatis的共生關(guān)系 | 需替換原有的SqlSessionFactoryBean | 對Mybatis沒有任何修改,原來怎么用還是怎么用 |
| 動態(tài)SQL構(gòu)造方式 | 應(yīng)用啟動時, 根據(jù)Entity注解信息構(gòu)造動態(tài)xml片段，注入到Mybatis解析器 | 應(yīng)用編譯時，根據(jù)Entity注解，編譯生成對應(yīng)方法的SqlProvider，利用mybatis的Mapper上@InsertProvider @SelectProvider @UpdateProvider注解關(guān)聯(lián) |
| 動態(tài)SQL結(jié)果是否容易DEBUG跟蹤 | 不容易debug | 容易，直接定位到SQLProvider方法上，設(shè)置斷點(diǎn)即可 |
| 動態(tài)SQL構(gòu)造 | 通過硬編碼字段名稱, 或者利用Entity的get方法的lambda表達(dá)式 | 通過編譯手段生成對應(yīng)的方法名，直接調(diào)用方法即可 |
| 字段變更后的錯誤發(fā)現(xiàn) | 通過get方法的lambda表達(dá)的可以編譯發(fā)現(xiàn)，通過字段編碼的無法編譯發(fā)現(xiàn) | 編譯時便可發(fā)現(xiàn) |
| 不同字段動態(tài)SQL構(gòu)造方法 | 通過接口參數(shù)方式 | 通過接口名稱方式, FluentAPI的編碼效率更高 |
| 語法渲染特點(diǎn) | 無 | 通過關(guān)鍵變量select, update, set, and, or可以利用IDE語法渲染, 可讀性更高 |