MybatisPlus 之 PaginationInterceptor 扩展配置bean

package com.dcits.branch.cloud.tran.configuration;
import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.core.parser.ISqlParser;
import com.baomidou.mybatisplus.extension.parsers.DynamicTableNameParser;
import com.baomidou.mybatisplus.extension.parsers.ITableNameHandler;
import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import com.dcits.branch.cloud.components.context.ContextManager;
import com.dcits.branch.cloud.components.context.ContextManagerImpl;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.reflection.wrapper.BeanWrapper;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 
 * 类功能：MybatisPlus 扩展配置bean
 * oracle 数据源切换 mysql,报错 MySQLSyntaxErrorException: Every derived table must have its own alias
 * 设置注意 paginationInterceptor.setDialectType(DbType.MYSQL.getDb());
 * 
 *
 * @author dcits.xupengfei 2019/3/9
 * @desc: MybatisPlus 扩展配置bean
 * @modify dcits.xupengfei 2020/3/9 初始创建
 */
@MapperScan({"com.dcits.branch.cloud.tran.order.dao.mapper", "com.dcits.branch.cloud.tran.prdbusi.dao.mapper"})
@Configuration
@Slf4j
public class MybatisPlusConfig {

    private final static String MPTBL_CM_TRAN_JOURNAL = "CM_TRAN_JOURNAL";

    @Bean
    public PaginationInterceptor paginationInterceptor() {
        PaginationInterceptor paginationInterceptor = new PaginationInterceptor();

        List sqlParserList = new ArrayList<>();
        // --- 动态表名映射
        DynamicTableNameParser dynamicTableNameParser = new DynamicTableNameParser();
        ITableNameHandler myTableNameHandler = (metaObject, sql, tableName) -> {
            Object objectWrapper = metaObject.getObjectWrapper();
            if (objectWrapper instanceof BeanWrapper) {
                BeanWrapper beanWrapper = (BeanWrapper) metaObject.getObjectWrapper();
                if (MPTBL_CM_TRAN_JOURNAL.equals(tableName)) {
                    log.debug("mapping table name :{}", tableName);

                  /*  ContextManager contextManager = ContextManagerImpl.getInstanse();
                    TableNameMapping tableNameMapping = contextManager.getContext(TableNameMapping.class);
                    String suffix = tableNameMapping.getSuffix(tableName);*/


                    //因update时 ParameterObject对象和insert时不一致,因此需要放弃使用mp的对象,用自定义对象获取表名后缀
                    /*
                    String delegate = beanWrapper.findProperty("delegate", true);

                    PropertyTokenizer prop2 = new PropertyTokenizer("delegate");
                    Object obj2 = beanWrapper.get(prop2);
                    PreparedStatementHandler ph = (PreparedStatementHandler) obj2;
                    Object bean = ph.getParameterHandler().getParameterObject();
                    //获取对象中分表属性
                    CmTranJournal cmTranJournal = (CmTranJournal) bean;
                    String suffix = cmTranJournal.getBusiType();
                    */
                    log.debug("mapping table name result:{}", tableName);
                    return tableName;
                }
            }
            //other table/bean not mapping tablename
            return null;
        };
        //defined which table to mapping
        Map tableNameHandlerMap = new HashMap<>();
        tableNameHandlerMap.put(MPTBL_CM_TRAN_JOURNAL, myTableNameHandler);
        dynamicTableNameParser.setTableNameHandlerMap(tableNameHandlerMap);
        sqlParserList.add(dynamicTableNameParser);
        paginationInterceptor.setSqlParserList(sqlParserList);
        paginationInterceptor.setDialectType(DbType.MYSQL.getDb());
        log.info("mybatis_plus_extend_plugin(paginationInterceptor): {}" + paginationInterceptor);
        return paginationInterceptor;
    }

}