tk.mybatis
mapper
3.4.0
非springboot项目引这个包
tk.mybatis
mapper-spring-boot-starter
2.0.2
springboot项目直接引这个包,本次我们将基于springboot进行开发,这里注意jar包版本,过低的版本将会出现问题,下面会介绍
package com.example.configuration;
import com.example.common.mapper.commonMapper.CommonMapper;
import org.mybatis.spring.boot.autoconfigure.MybatisAutoConfiguration;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import tk.mybatis.spring.mapper.MapperScannerConfigurer;
import java.util.Properties;
@Configuration
@AutoConfigureAfter(MybatisAutoConfiguration.class)
public class MyBatisConfiguration {
@Bean
public MapperScannerConfigurer mapperScannerConfigurer() {
MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
mapperScannerConfigurer.setSqlSessionFactoryBeanName("sqlSessionFactory");
mapperScannerConfigurer.setBasePackage("com.example.dao.mapper");
Properties properties = new Properties();
properties.setProperty("mappers", CommonMapper.class.getName());
properties.setProperty("notEmpty", "false");
properties.setProperty("identity", "MYSQL");
properties.setProperty("order","BEFORE");
mapperScannerConfigurer.setProperties(properties);
return mapperScannerConfigurer;
}
}
1>CommonMapper这个是我们自己定义的通用mapper,它放置一个单独的包下面。也就是说这个包下面只有这个一个mapper,否则我们在实用泛型时会出现类型转换的问题。(我在这里纠结了好久)
2>这里我们配置了自定义mapper的扫描路径。注意springboot项目一定要注意jar包版本,版本过低的话,在配置类中的定义是没有用的。还是扫描不到,我之前使用的版本1.2.3就会出现这个问题,更换更高的版本就可以解决了。
因为我们使用的是mysql数据库,所以在使用通用功能的时候就选择性引入一些经常使用的方法,下面是自己定义的常用mapper类的整合(这里会抛弃一些不常用的类或不是mysql的方法类)。这些基类不要放在 BasePackage的路径下,这个路径下的mapper都是要指定明确的泛型类型的。
1 > 提供查询功能Mapper:
package com.example.common.mapper.basics;
import tk.mybatis.mapper.common.Marker;
import tk.mybatis.mapper.common.base.select.*;
import tk.mybatis.mapper.common.condition.SelectByConditionMapper;
import tk.mybatis.mapper.common.condition.SelectCountByConditionMapper;
import tk.mybatis.mapper.common.example.SelectByExampleMapper;
import tk.mybatis.mapper.common.ids.SelectByIdsMapper;
/**
* @desc 基础查询功能mapper
*
*/
public interface SelectMapper<T> extends Marker,
SelectOneMapper<T>,
tk.mybatis.mapper.common.base.select.SelectMapper<T>,
SelectAllMapper<T>,
SelectCountMapper<T>,
SelectByPrimaryKeyMapper<T>,
ExistsWithPrimaryKeyMapper<T>,
SelectByIdsMapper<T>,
SelectByConditionMapper<T>,
SelectCountByConditionMapper<T>,
SelectByExampleMapper<T> {
}
2>提供新增功能mapper
package com.example.common.mapper.basics;
import tk.mybatis.mapper.common.Marker;
import tk.mybatis.mapper.common.MySqlMapper;
import tk.mybatis.mapper.common.base.insert.InsertSelectiveMapper;
/**
* @desc 基础插入功能mapper
*/
public interface InsertMapper<T> extends Marker,
tk.mybatis.mapper.common.base.insert.InsertMapper<T>,
InsertSelectiveMapper<T>,
MySqlMapper<T>{
}
3>提供更新功能mapper
package com.example.common.mapper.basics;
import tk.mybatis.mapper.common.Marker;
import tk.mybatis.mapper.common.base.update.UpdateByPrimaryKeyMapper;
import tk.mybatis.mapper.common.base.update.UpdateByPrimaryKeySelectiveMapper;
import tk.mybatis.mapper.common.condition.UpdateByConditionMapper;
import tk.mybatis.mapper.common.condition.UpdateByConditionSelectiveMapper;
import tk.mybatis.mapper.common.example.UpdateByExampleSelectiveMapper;
/**
* @desc 基础更新功能mapper
*
*/
public interface UpdateMapper<T> extends Marker,
UpdateByPrimaryKeyMapper<T>,
UpdateByPrimaryKeySelectiveMapper<T>,
UpdateByConditionMapper<T>,
UpdateByConditionSelectiveMapper<T>,
UpdateByExampleSelectiveMapper<T> {
}
4>提供删除功能mapper
package com.example.common.mapper.basics;
import com.example.common.mapper.defined.DeleteShamByIdsMapper;
import tk.mybatis.mapper.common.Marker;
import tk.mybatis.mapper.common.base.delete.DeleteByPrimaryKeyMapper;
import tk.mybatis.mapper.common.condition.DeleteByConditionMapper;
import tk.mybatis.mapper.common.ids.DeleteByIdsMapper;
/**
* @desc 基础删除功能mapper
*
*/
public interface DeleteMapper<T> extends Marker,
tk.mybatis.mapper.common.base.delete.DeleteMapper<T>,
DeleteByPrimaryKeyMapper<T>,
DeleteByConditionMapper<T>,
DeleteByIdsMapper<T>{
}
5>提供增删改查的基类 CommonMapper
package com.example.common.mapper.commonMapper;
import com.example.common.mapper.basics.DeleteMapper;
import com.example.common.mapper.basics.InsertMapper;
import com.example.common.mapper.basics.SelectMapper;
import com.example.common.mapper.basics.UpdateMapper;
/**
* @param
* @desc 基础增删改查功能mapper
*/
public interface CommonMapper<T> extends
DeleteMapper<T>,
InsertMapper<T>,
SelectMapper<T>,
UpdateMapper<T> {
}
6>实体对象
package com.example.dao.entity;
import lombok.Data;
import javax.persistence.Id;
import javax.persistence.Table;
import java.io.Serializable;
@Table(name="user")
@Data
public class User implements Serializable {
@Id
private Integer id;
private String trueName;
private String userName;
private Integer isDeleted;
}
7>让自定义mapper继承CommenMapper,就可以使用这些语句了
package com.example.dao.mapper;
import com.example.common.mapper.commonMapper.CommonMapper;
import com.example.dao.entity.User;
public interface UserMapper extends CommonMapper<User> {
}
1>我们自定义的Provider需要去继承 MapperTemplate并覆写构造方法
这个是源码中的批量删除
//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//
package tk.mybatis.mapper.provider;
import java.util.Set;
import org.apache.ibatis.mapping.MappedStatement;
import tk.mybatis.mapper.MapperException;
import tk.mybatis.mapper.entity.EntityColumn;
import tk.mybatis.mapper.mapperhelper.EntityHelper;
import tk.mybatis.mapper.mapperhelper.MapperHelper;
import tk.mybatis.mapper.mapperhelper.MapperTemplate;
import tk.mybatis.mapper.mapperhelper.SqlHelper;
public class IdsProvider extends MapperTemplate {
public IdsProvider(Class<?> mapperClass, MapperHelper mapperHelper) {
super(mapperClass, mapperHelper);
}
public String deleteByIds(MappedStatement ms) {
Class<?> entityClass = this.getEntityClass(ms);
StringBuilder sql = new StringBuilder();
sql.append(SqlHelper.deleteFromTable(entityClass, this.tableName(entityClass)));
Set<EntityColumn> columnList = EntityHelper.getPKColumns(entityClass);
if (columnList.size() == 1) {
EntityColumn column = (EntityColumn)columnList.iterator().next();
sql.append(" where ");
sql.append(column.getColumn());
sql.append(" in (${_parameter})");
return sql.toString();
} else {
throw new MapperException("继承 deleteByIds 方法的实体类[" + entityClass.getCanonicalName() + "]中必须只有一个带有 @Id 注解的字段");
}
}
public String selectByIds(MappedStatement ms) {
Class<?> entityClass = this.getEntityClass(ms);
this.setResultType(ms, entityClass);
StringBuilder sql = new StringBuilder();
sql.append(SqlHelper.selectAllColumns(entityClass));
sql.append(SqlHelper.fromTable(entityClass, this.tableName(entityClass)));
Set<EntityColumn> columnList = EntityHelper.getPKColumns(entityClass);
if (columnList.size() == 1) {
EntityColumn column = (EntityColumn)columnList.iterator().next();
sql.append(" where ");
sql.append(column.getColumn());
sql.append(" in (${_parameter})");
return sql.toString();
} else {
throw new MapperException("继承 selectByIds 方法的实体类[" + entityClass.getCanonicalName() + "]中必须只有一个带有 @Id 注解的字段");
}
}
}
接下来我们对IdsProvider 进行扩展使他支持批量逻辑删除
1>创建IdsProvider的子类
package com.example.common.mapper.defined;
import org.apache.ibatis.mapping.MappedStatement;
import tk.mybatis.mapper.MapperException;
import tk.mybatis.mapper.entity.EntityColumn;
import tk.mybatis.mapper.mapperhelper.EntityHelper;
import tk.mybatis.mapper.mapperhelper.MapperHelper;
import tk.mybatis.mapper.mapperhelper.SqlHelper;
import tk.mybatis.mapper.provider.IdsProvider;
import java.util.Set;
public class IdsProviderDefined extends IdsProvider {
public IdsProviderDefined(Class<?> mapperClass, MapperHelper mapperHelper) {
super(mapperClass, mapperHelper);
}
public String deleteShamByIds(MappedStatement ms) {
Class<?> entityClass = this.getEntityClass(ms);
StringBuilder sql = new StringBuilder();
sql.append(SqlHelper.updateTable(entityClass, this.tableName(entityClass)));
sql.append(" is_deleted='1' ");
Set<EntityColumn> columnList = EntityHelper.getPKColumns(entityClass);
if (columnList.size() == 1) {
EntityColumn column = (EntityColumn)columnList.iterator().next();
sql.append(" where ");
sql.append(column.getColumn());
sql.append(" in (${_parameter})");
return sql.toString();
} else {
throw new MapperException("继承 deleteByIds 方法的实体类[" + entityClass.getCanonicalName() + "]中必须只有一个带有 @Id 注解的字段");
}
}
}
deleteShamByIds就是我们门批量逻辑删除的方法,这个方法其实就是再拼装sql,tk中提供了很多帮助我们拼装sql,和参数的类(SqlHelper,EntityHelper),我们可以使用
2>创建DeleteShamByIdsMapper接口
package com.example.common.mapper.defined;
import org.apache.ibatis.annotations.DeleteProvider;
public interface DeleteShamByIdsMapper<T> {
@DeleteProvider(
type = IdsProviderDefined.class,
method = "dynamicSQL"
)
int deleteShamByIds(String var1);
//这里的抽象方法的名称必须和IdsProviderDefined 中的方法一致
}
3>在DeleteMapper中继承我们自定义的逻辑删除接口DeleteShamByIdsMapper
package com.example.common.mapper.basics;
import com.example.common.mapper.defined.DeleteShamByIdsMapper;
import tk.mybatis.mapper.common.Marker;
import tk.mybatis.mapper.common.base.delete.DeleteByPrimaryKeyMapper;
import tk.mybatis.mapper.common.condition.DeleteByConditionMapper;
import tk.mybatis.mapper.common.ids.DeleteByIdsMapper;
/**
* @desc 基础删除功能mapper
*
*/
public interface DeleteMapper<T> extends Marker,
tk.mybatis.mapper.common.base.delete.DeleteMapper<T>,
DeleteByPrimaryKeyMapper<T>,
DeleteByConditionMapper<T>,
DeleteByIdsMapper<T>,
DeleteShamByIdsMapper<T>{
}
到这里我们自定义的批量逻辑删除就定义好了,我们可以通过这种方式扩展通用mapper
大家有什么更好的方式欢迎留言