讀取excle數據和讀取CSV數據

讀取excle數據

依賴

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>3.17</version>
</dependency>

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.17</version>
</dependency>

<dependency>
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>1.2.16</version>
</dependency>

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-collections4</artifactId>
    <version>4.1</version>
</dependency>

<dependency>
    <groupId>org.apache.xmlbeans</groupId>
    <artifactId>xmlbeans</artifactId>
    <version>3.0.2</version>
</dependency>

工具類

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.text.DateFormat;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.apache.log4j.Logger;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

/**
 * @author wyc
 * @date 2019/8/7 15:28
 */
public class ReadExcelUtil {


    private static final Logger logger = Logger.getLogger(ExportUtil.class);

        private static final String EXCEL_XLS = ".xls";
        private static final String EXCEL_XLSX = ".xlsx";

        /**
         *讀取excel數據
         * @throws Exception
         *
         */
        public static List<List<String>> readExcelInfo(String url) throws Exception{
            /*
             * workbook:工作簿,就是整個Excel文檔
             * sheet:工作表
             * row:行
             * cell:單元格
             */

//        BufferedWriter bw = new BufferedWriter(new FileWriter(new File(url)));
//        支持excel2003、2007
            File excelFile = new File(url);//創建excel文件對象
            InputStream is = new FileInputStream(excelFile);//創建輸入流對象
            checkExcelVaild(excelFile);
//            Workbook workbook = getWorkBook(is, excelFile);  //有點問題
        Workbook workbook = WorkbookFactory.create(is);//同時支持2003、2007、2010
//        獲取Sheet數量
            int sheetNum = workbook.getNumberOfSheets();
//      創建二維數組保存所有讀取到的行列數據，外層存行數據，內層存單元格數據
            List<List<String>> dataList = new ArrayList<List<String>>();
//        FormulaEvaluator formulaEvaluator = null;
//        遍歷工作簿中的sheet,第一層循環所有sheet表
            for(int index = 0;index<sheetNum;index++){
                Sheet sheet = workbook.getSheetAt(index);
                if(sheet==null){
                    continue;
                }
                System.out.println("表單行數："+sheet.getLastRowNum());
//            如果當前行沒有數據跳出循環，第二層循環單sheet表中所有行
                for(int rowIndex=0;rowIndex<=sheet.getLastRowNum();rowIndex++){
                    Row row = sheet.getRow(rowIndex);
//                根據文件頭可以控制從哪一行讀取，在下面if中進行控制
                    if(row==null){
                        continue;
                    }
//                遍歷每一行的每一列，第三層循環行中所有單元格
                    List<String> cellList = new ArrayList<String>();
                    for(int cellIndex=0;cellIndex<row.getLastCellNum();cellIndex++){
                        Cell cell = row.getCell(cellIndex);
                        cellList.add(getCellValue(cell));
                    }
                    dataList.add(cellList);
                }

            }
            is.close();
            return dataList;
        }
        /**
         *獲取單元格的數據,暫時不支持公式
         *
         *
         */
        public static String getCellValue(Cell cell){
            CellType cellType = cell.getCellTypeEnum();
            String cellValue = "";
            if(cell==null || cell.toString().trim().equals("")){
                return null;
            }

            if(cellType==CellType.STRING){
                cellValue = cell.getStringCellValue().trim();

                return cellValue = isBlank(cellValue) ? "" : cellValue;
            }
            if(cellType==CellType.NUMERIC){
                if (HSSFDateUtil.isCellDateFormatted(cell)) {  //判斷日期類型
                    cellValue = DateToString(cell.getDateCellValue());
                } else {  //否
                    cellValue = new DecimalFormat("#.######").format(cell.getNumericCellValue());
                }
                return cellValue;
            }
            if(cellType==CellType.BOOLEAN){
                cellValue = String.valueOf(cell.getBooleanCellValue());
                return cellValue;
            }
            return null;

        }
        /**
         *判斷excel的版本，並根據文件流數據獲取workbook
         * @throws IOException
         *
         */
        public static Workbook getWorkBook(InputStream is,File file) throws Exception{

            Workbook workbook = null;
            if(file.getName().endsWith(EXCEL_XLS)){
                workbook = new HSSFWorkbook(is);
            }else if(file.getName().endsWith(EXCEL_XLSX)){
                workbook = new XSSFWorkbook(is);
            }

            return workbook;
        }
        /**
         *校驗文件是否爲excel
         * @throws Exception
         */
        public static void checkExcelVaild(File file) throws Exception {
            String message = "該文件是EXCEL文件！";
            if(!file.exists()){
                message = "文件不存在！";
                throw new Exception(message);
            }
            if(!file.isFile()||((!file.getName().endsWith(EXCEL_XLS)&&!file.getName().endsWith(EXCEL_XLSX)))){
                System.out.println(file.isFile()+"==="+file.getName().endsWith(EXCEL_XLS)+"==="+file.getName().endsWith(EXCEL_XLSX));
                System.out.println(file.getName());
                message = "文件不是Excel";
                throw new Exception(message);
            }
        }
    /**
     * 將date類型轉換爲String類型
     * @param date
     */
    private static String DateToString(Date date) {
        if (date == null) {
            date = new Date();
        }
        DateFormat format1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        return format1.format(date);
    }

    /**
     * 判斷字符串是否爲空
     * @return true:空，false:非空
     */
    private static boolean isBlank(String s){
        if(s == null){
            return true;
        }
        if("".equals(s)){
            return true;
        }
        if("".equals(s.trim())){
            return true;
        }
        return false;
    }
}

main方法測試

    public static void main(String[] args) throws Exception {
    //外層集合裝的是每一行的數據,內層集合裝的是每一行中每列的數據
        List<List<String>> list = readExcelInfo("D:\\aaa.xlsx");
        for (List<String> stringList : list) {
            System.out.println(stringList);
            //......處理數據
        }
    }

讀取CSV數據

依賴

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>lang3</artifactId>
    <version>3.1.0</version>
</dependency>

<dependency>
    <groupId>com.opencsv</groupId>
    <artifactId>opencsv</artifactId>
    <version>4.4</version>
</dependency>

工具類

import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * @author wyc
 * @date 2019/8/7 16:26
 */
public class ReadCsvUtil {

    public static List<List<String>> readCsv() {
        List<List<String>> records = new ArrayList<>();
        String record;
        // 設定UTF-8字符集，使用帶緩衝區的字符輸入流BufferedReader讀取文件內容
        BufferedReader file = null;
        try {
            file = new BufferedReader(new InputStreamReader(new FileInputStream("D:\\bbb.csv"), "GBK"));
             file.readLine(); //跳過表頭所在的行
            // 遍歷數據行並存儲在名爲records的ArrayList中
            while ((record = file.readLine()) != null) {
                String fields[] = record.split(",");
                List<String> list = Arrays.asList(fields);
                records.add(list);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if (file!= null){
                try {
                    // 關閉文件
                    file.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return records;

    }
}

main方法測試

    public static void main(String[] args) {
        List<List<String>> lists = readCsv();
        System.out.println(lists);
        for (List<String> list : lists) {
            System.out.println(list);
            //.......處理數據
        }
    }