/**
 * @Version: 1.0.0
 * @Author: Dragon_王
 * @ClassName: ExcelUtils
 * @Description: Excel相關(guān)工具類
 * @Date: 2024/3/9 11:24
 */

import cn.hutool.core.collection.CollUtil;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.support.ExcelTypeEnum;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Excel 相關(guān)工具類
 */
@Slf4j
public class ExcelUtils {

    /**
     * excel 轉(zhuǎn) csv
     *
     * @param multipartFile
     * @return
     */
    public static String excelToCsv(MultipartFile multipartFile) {
        // 讀取數(shù)據(jù)
        List<Map<Integer, String>> list = null;
        try {
            list = EasyExcel.read(multipartFile.getInputStream()).excelType(ExcelTypeEnum.XLSX).sheet().headRowNumber(0).doReadSync();
        } catch (IOException e) {
            log.error("表格處理錯(cuò)誤", e);
        }
        if (CollUtil.isEmpty(list)) {
            return "";
        }
        // 轉(zhuǎn)換為 csv
        StringBuilder stringBuilder = new StringBuilder();
        // 讀取表頭
        LinkedHashMap<Integer, String> headerMap = (LinkedHashMap) list.get(0);
        List<String> headerList = headerMap.values().stream().filter(ObjectUtils::isNotEmpty).collect(Collectors.toList());
        stringBuilder.append(StringUtils.join(headerList, ",")).append("\n");
        // 讀取數(shù)據(jù)
        for (int i = 1; i < list.size(); i++) {
            LinkedHashMap<Integer, String> dataMap = (LinkedHashMap) list.get(i);
            List<String> dataList = dataMap.values().stream().filter(ObjectUtils::isNotEmpty).collect(Collectors.toList());
            stringBuilder.append(StringUtils.join(dataList, ",")).append("\n");
        }
        return stringBuilder.toString();
    }
}

//傳入的是Excel文件，不是路徑哦
ExcelUtils.excelToCsv(Excel文件);

        //定義表名
        String tableName = "test";
        //獲取第一個(gè)換行符的索引
        int index = csvData.indexOf("\n");
        //分割出屬性名字符串，如"日期,閱讀量"
        String colum = csvData.substring(0,index);
        //得到屬性名數(shù)組，如{"日期","閱讀量"}
        String[] colums = colum.split(",");
        //得到全部屬性值字符串，如"3,253\n4,408\n5,363\n6,955\n7,496\n8,1310\n9,748"
        String data = csvData.substring(index).trim();
        //得到全部屬性值數(shù)組，如：{"3,253","4,408","5,363""6,955".......}
        String[] split_data = data.split("\n");
        //調(diào)用建表
        tableCreationUtils.createTable(tableName,colums);
        //調(diào)用插入
        tableCreationUtils.Dynamicinsert(tableName,colums,split_data);

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;

import javax.sql.DataSource;
import java.sql.SQLException;


/**
 * 構(gòu)建生成表sql
 *
 * @version 1.0.0
 * @Author: dragon_王
 * @Date: 2024/3/11 20:45:16
 */
@Component
public class TableCreationUtils {

    private final JdbcTemplate jdbcTemplate;
    @Autowired
    public TableCreationUtils(DataSource dataSource){
        this.jdbcTemplate = new JdbcTemplate(dataSource);
    }

    /**
     * 動(dòng)態(tài)構(gòu)建創(chuàng)建表的sql語句并執(zhí)行
     *
     * @param tableName 表名字符串
     * @param columnNames 屬性名數(shù)組
     * @return: void
     * @Date: 2024-03-13 23:23:36
     */
    public  void createTable(String tableName, String[] columnNames) {
        String sql = "CREATE TABLE " + tableName + " (";
        for (int i = 0; i < columnNames.length; i++) {
            sql += columnNames[i] + " VARCHAR(255)";
            if (i < columnNames.length - 1) {
                sql += ", ";
            }
        }
        sql += ");";
        jdbcTemplate.execute(sql);
    }

    /**
     * 動(dòng)態(tài)構(gòu)建插入sql語句并執(zhí)行
     *
     * @param tableName 表名字符串
     * @param columnName 屬性名數(shù)組，如{"日期"，"閱讀"}
     * @param rowData 屬性值數(shù)組，如{"3,253","4,408","5,363""6,955".......}
     * @return: void
     * @Date: 2024-03-13 23:24:09
     */
    public void Dynamicinsert(String tableName, String[] columnName,String[] rowData) throws SQLException {
        //屬性值為空就拋出異常
        if (rowData == null || rowData.length == 0) {
            throw new IllegalArgumentException("Row data must not be null or empty");
        }

        for (int i = 0;i < rowData.length;i++){
            //傳進(jìn)來的是所有屬性值數(shù)組，如：{"3,253","4,408","5,363""6,955".......}
            //所以以將每個(gè)元素取出以英文逗號(hào)分割，得到插入的每行元素如["3","253"]
            String[] row = rowData[i].split(",");
            // 構(gòu)建占位符
            StringBuilder columnNames = new StringBuilder();
            StringBuilder placeholders = new StringBuilder();
            for (int j = 0; j < row.length; j++) {
                if (j > 0) {
                    columnNames.append(", ");
                    placeholders.append(", ");
                }
                columnNames.append(columnName[j]);
                placeholders.append("?"); // 使用?作為PreparedStatement的占位符
            }

            // 構(gòu)建完整的SQL語句
            String sql = "INSERT INTO " + tableName + " (" + columnNames + ") VALUES (" + placeholders + ")";

            // 使用JdbcTemplate執(zhí)行插入操作，如第一次循環(huán)：insert into tablename (日期,閱讀) values (?,?)
            //row：["3","253"]
            jdbcTemplate.update(sql,row);
        }
    }

}