五、spring boot整合mybatis-plus
阿新 • • 發佈：2019-02-28
nta 下劃線 問題 action least 類型 inter auto detail spring boot整合mybatis-plus
簡介
mybatis 增強工具包，簡化 CRUD 操作。 文檔
http://mp.baomidou.com
http://mybatis.plus
優點 | Advantages
- 無侵入：Mybatis-Plus 在 Mybatis 的基礎上進行擴展，只做增強不做改變，引入 Mybatis-Plus 不會對您現有的 Mybatis 構架產生任何影響，而且 MP 支持所有 Mybatis 原生的特性
- 依賴少：僅僅依賴 Mybatis 以及 Mybatis-Spring
- 損耗小：啟動即會自動註入基本CURD，性能基本無損耗，直接面向對象操作
- 預防Sql註入：內置Sql註入剝離器，有效預防Sql註入***
- 通用CRUD操作：內置通用Mapper、通用Service，僅僅通過少量配置即可實現單表大部分 CRUD 操作，更有強大的條件構造器，滿足各類使用需求
- 多種主鍵策略：支持多達4種主鍵策略（內含分布式唯一ID生成器），可自由配置，完美解決主鍵問題
- 支持熱加載：Mapper 對應的 XML 支持熱加載，對於簡單的 CRUD 操作，甚至可以無 XML 啟動
- 支持ActiveRecord：支持 ActiveRecord 形式調用，實體類只需繼承 Model 類即可實現基本 CRUD 操作
- 支持代碼生成：采用代碼或者 Maven 插件可快速生成 Mapper 、 Model 、 Service 、 Controller 層代碼，支持模板引擎，更有超多自定義配置等您來使用（P.S. 比 Mybatis 官方的 Generator 更加強大！）
- 支持自定義全局通用操作：支持全局通用方法註入（ Write once, use anywhere ）
- 支持關鍵詞自動轉義：支持數據庫關鍵詞（order、key......）自動轉義，還可自定義關鍵詞
- 內置分頁插件：基於Mybatis物理分頁，開發者無需關心具體操作，配置好插件之後，寫分頁等同於寫基本List查詢
- 內置性能分析插件：可輸出Sql語句以及其執行時間，建議開發測試時啟用該功能，能有效解決慢查詢
- 內置全局攔截插件：提供全表 delete 、 update 操作智能分析阻斷，預防誤操作
前面已經 創建了一個springboot項目，我們直接在該項目上整合mybatis-plus
準備工作
-
pom.xml jar引入： <mybatis-plus.version>3.0.6</mybatis-plus.version>
<dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>${mybatis-plus.version}</version> </dependency> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus</artifactId> <version>${mybatis-plus.version}</version> </dependency> - 創建表
CREATE TABLE `my_info` ( `id` int(10) NOT NULL AUTO_INCREMENT, `name` varchar(255) DEFAULT NULL, `age` int(3) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;項目結構
創建基本的項目結構，controller、dao、entity、service(impl)
如圖：
controller :
@RestController
public class MyInfoController {
@Resource
MyInfoService myInfoService;
@GetMapping("myInfo")
public String myInfo(@RequestParam Integer id) {
MyInfo myInfo = myInfoService.getById(id);
return myInfo.toString();
}
}
dao :
public interface MyInfoMapper extends BaseMapper<MyInfo> {
}
entity :
@Data
@TableName(value = "my_info")
public class MyInfo {
@TableId(type = IdType.AUTO)
private Integer id;
private String name;
private Integer age;
}
service :
public interface MyInfoService {
MyInfo getById(int id);
}
impl :
@Service("myInfoService")
public class MyInfoServiceImpl extends ServiceImpl<MyInfoMapper,MyInfo> implements MyInfoService {
@Override
public MyInfo getById(int id) {
return baseMapper.selectById(id);
}
}
當前，我們也可以在xml中自定義sql( MyInfoMapper.xml )
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.honghh.bootfirst.dao.MyInfoMapper">
<!--自定義SQL-->
</mapper>
application.yml 配置文件內容如下
spring:
datasource:
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/boot_demo
username: root
password: 123456
#mybatis
mybatis-plus:
mapper-locations: classpath*:mapper/**/*.xml
#實體掃描，多個package用逗號或者分號分隔
typeAliasesPackage: com.honghh.bootfirst.entity
global-config:
#主鍵類型 0:"數據庫ID自增", 1:"用戶輸入ID",2:"全局唯一ID (數字類型唯一ID)", 3:"全局唯一ID UUID";
id-type: 0
#字段策略 0:"忽略判斷",1:"非 NULL 判斷"),2:"非空判斷"
field-strategy: 2
#駝峰下劃線轉換
db-column-underline: true
#刷新mapper 調試神器
refresh-mapper: true
#數據庫大寫下劃線轉換
#capital-mode: true
# Sequence序列接口實現類配置
#key-generator: com.baomidou.mybatisplus.incrementer.OracleKeyGenerator
#邏輯刪除配置
#logic-delete-value: -1
#logic-not-delete-value: 0
#自定義填充策略接口實現
#meta-object-handler: com.baomidou.springboot.xxx
#自定義SQL註入器
sql-injector: com.baomidou.mybatisplus.mapper.LogicSqlInjector
configuration:
map-underscore-to-camel-case: true
cache-enabled: false
call-setters-on-nulls: true
啟動項目
完成上面的步驟，準備工作將近完成，現在開始啟動項目，但是你會發現項目啟動不起來，報錯如下：
org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘myInfoController‘: Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name ‘myInfoService‘: Unsatisfied dependency expressed through field ‘baseMapper‘; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type ‘com.honghh.bootfirst.dao.MyInfoMapper‘ available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:324) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1395) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:849) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.__refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.jrLockAndRefresh(AbstractApplicationContext.java:40002) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:41008) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.3.RELEASE.jar:2.1.3.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.3.RELEASE.jar:2.1.3.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.3.RELEASE.jar:2.1.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.3.RELEASE.jar:2.1.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.3.RELEASE.jar:2.1.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.3.RELEASE.jar:2.1.3.RELEASE]
at com.honghh.bootfirst.BootFirstApplication.main(BootFirstApplication.java:11) [classes/:na]
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name ‘myInfoService‘: Unsatisfied dependency expressed through field ‘baseMapper‘; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type ‘com.honghh.bootfirst.dao.MyInfoMapper‘ available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:596) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1395) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:204) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.resolveBeanByName(AbstractAutowireCapableBeanFactory.java:452) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:526) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:496) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$ResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:636) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:180) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:321) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE]
... 19 common frames omitted
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type ‘com.honghh.bootfirst.dao.MyInfoMapper‘ available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1654) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1213) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1167) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
... 35 common frames omitted上網查了一下，說一般是下面原因造成的：
- 1.applicationContext.xml配置中沒有掃描包
- 2.controller層的@controller或者service層的@Service註解沒寫
- 3.service註入mapper失敗
仔細看了下代碼是mapper層沒有註入，mapper註入方法有一下幾種方式。
- 1.直接在mapper上寫註解
@Mapper
public interface MyInfoMapper extends BaseMapper<MyInfo> {
}
- 2.在啟動類上添加註解
@EnableTransactionManagement
@SpringBootApplication
@MapperScan("com.honghh.*.dao")
public class BootFirstApplication {
public static void main(String[] args) {
SpringApplication.run(BootFirstApplication.class, args);
}
}
mybatis-config中只是會為對應的mapper創建代理類，而想真正包裝成bean，註入到spring容器中，還是需要靠AutoConfiguredMapperScannerRegistrar，它會根據掃描@Mapper註釋或是@MapperScan指定的包下的接口，將其註冊為bean。
- 3.也可以寫一個配置類 MybatisPlusConfig
@Configuration
@MapperScan(basePackages = "com.honghh.*.dao")
public class MybatisPlusConfig {
/**
* mybatis-plus 分頁插件
*/
@Bean
public PerformanceInterceptor performanceInterceptor() {
return new PerformanceInterceptor();
}
}
在瀏覽器中輸入 ：http://localhost:8080/myInfo?id=1 顯示如下
成功！！！此時你已經學會了整合mybatis-plus
參考文本
https://gitee.com/baomidou/mybatisplus-spring-boot
文章來源 ： https://blog.csdn.net/qq_35098526/article/details/87782961
五、spring boot整合mybatis-plus