详解扩展tk.mybatis的批量更新的功能

import org.apache.ibatis.annotations.UpdateProvider;

import java.util.List;


@tk.mybatis.mapper.annotation.ReGISterMapper
public interface UpdateBatchByPrimaryKeySelectiveMapper<T> {

    
    @UpdateProvider(type = BatchExampleProvider.class, method = "dynamicsql")
    int updateBatchByPrimaryKeySelective(List<? extends T> recordList);

}

import org.apache.ibatis.mapping.MappedStatement;
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.ExampleProvider;

import java.util.Set;



public class BatchExampleProvider extends ExampleProvider {

    public BatchExampleProvider(Class<?> mapperClass, MapperHelper mapperHelper) {
        super(mapperClass, mapperHelper);
    }


    
    public String updateBatchByPrimaryKeySelective(MappedStatement ms) {
        final Class<?> entityClass = getEntityClass(ms);
        //开始拼sql
        StringBuilder sql = new StringBuilder();
        sql.append(SqlHelper.updateTable(entityClass, tableName(entityClass)));
        sql.append("<trim prefix=\"set\" suffixOverrides=\",\">");

        //获取全部列
        Set<EntityColumn> columnList = EntityHelper.getColumns(entityClass);
        for (EntityColumn column : columnList) {
            if (!column.isId() && column.isUpdatable()) {
                sql.append("  <trim prefix=\""+column.getColumn()+" =case\" suffix=\"end,\">");
                sql.append("    <foreach collection=\"list\" item=\"i\" index=\"index\">");
                sql.append("      <if test=\"i."+column.getEntityField().getName()+"!=null\">");
                sql.append("         when id=#{i.id} then #{i."+column.getEntityField().getName()+"}");
                sql.append("      </if>");
                sql.append("    </foreach>");
                sql.append("  </trim>");
            }
        }

        sql.append("</trim>");
        sql.append("WHERE");
        sql.append(" id IN ");
        sql.append("<trim prefix=\"(\" suffix=\")\">");
        sql.append("<foreach collection=\"list\" separator=\", \" item=\"i\" index=\"index\" >");
        sql.append("#{i.id}");
        sql.append("</foreach>");
        sql.append("</trim>");

        return sql.toString();
    }
}

@tk.mybatis.mapper.annotation.RegisterMapper
public interface BatchMapper<T> extends
        UpdateBatchByPrimaryKeySelectiveMapper<T> {
}

List<List<BatchTest>> splitList = ListUtils.splitList(list, 100);
        splitList.forEach(data -> {
            batchTestMapper.updateBatchByPrimaryKeySelective(data);
        });