Java解析Excel工具類(兼容xls和xlsx)

 

依賴jar

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>4.0.1</version>
        </dependency>

 

ExcelUtils.java

package javax.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.math.BigDecimal;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.DateUtil;
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.xssf.usermodel.XSSFWorkbook;

/**
 * Excel 工具類(兼容xls和xlsx)
 * 
 * @author Logan
 * @version 1.0.0
 * @createDate 2019-03-07
 *
 */
public class ExcelUtils {

    private static final String XLS = "xls";
    private static final String XLSX = "xlsx";
    private static final DateFormat FORMAT = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");

    /**
     * 輸出數據到自定義模版的Excel輸出流
     * 
     * @param excelTemplate 自定義模版文件
     * @param data 數據
     * @param outputStream Excel輸出流
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static void writeDataToTemplateOutputStream(File excelTemplate, List<List<Object>> data, OutputStream outputStream) throws IOException {
        Workbook book = ExcelUtils.getWorkbookFromExcel(excelTemplate);
        ExcelUtils.writeDataToWorkbook(null, data, book, 0);
        ExcelUtils.writeWorkbookToOutputStream(book, outputStream);
    }

    /**
     * 從Excel文件獲取Workbook對象
     * 
     * @param excelFile Excel文件
     * @return Workbook對象
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static Workbook getWorkbookFromExcel(File excelFile) throws IOException {
        try (
                InputStream inputStream = new FileInputStream(excelFile);
        ) {

            if (excelFile.getName().endsWith(XLS)) {
                return new HSSFWorkbook(inputStream);
            }

            else if (excelFile.getName().endsWith(XLSX)) {
                return new XSSFWorkbook(inputStream);
            }

            else {
                throw new IOException("文件類型錯誤");
            }
        }
    }

    /**
     * 把Workbook對象內容輸出到Excel文件
     * 
     * @param book Workbook對象
     * @param file Excel文件
     * @throws FileNotFoundException 找不到文件異常，文件已建立，實際不存在該異常
     * @throws IOException 輸入輸出異常
     */
    public static void writeWorkbookToFile(Workbook book, File file) throws FileNotFoundException, IOException {
        if (!file.exists()) {
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdirs();
            }
            file.createNewFile();
        }
        try (
                OutputStream outputStream = new FileOutputStream(file);
        ) {
            writeWorkbookToOutputStream(book, outputStream);
        }
    }

    /**
     * 把Workbook對象輸出到Excel輸出流
     * 
     * @param book Workbook對象
     * @param outputStream Excel輸出流
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static void writeWorkbookToOutputStream(Workbook book, OutputStream outputStream) throws IOException {
        book.write(outputStream);
    }

    /**
     * 輸出數據到Workbook對象中指定頁碼
     * 
     * @param title 標題，寫在第一行，可傳null
     * @param data 數據
     * @param book Workbook對象
     * @param page 輸出數據到Workbook指定頁碼的頁面數
     */
    public static void writeDataToWorkbook(List<String> title, List<List<Object>> data, Workbook book, int page) {
        Sheet sheet = book.getSheetAt(page);

        Row row = null;
        Cell cell = null;

        // 設置表頭
        if (null != title && !title.isEmpty()) {
            row = sheet.getRow(0);
            if (null == row) {
                row = sheet.createRow(0);
            }

            for (int i = 0; i < title.size(); i++) {
                cell = row.getCell(i);
                if (null == cell) {
                    cell = row.createCell(i);
                }
                cell.setCellValue(title.get(i));
            }
        }

        List<Object> rowData = null;
        for (int i = 0; i < data.size(); i++) {

            row = sheet.getRow(i + 1);
            if (null == row) {
                row = sheet.createRow(i + 1);
            }

            rowData = data.get(i);
            if (null == rowData) {
                continue;
            }
            for (int j = 0; j < rowData.size(); j++) {
                cell = row.getCell(j);
                if (null == cell) {
                    cell = row.createCell(j);
                }
                setValue(cell, rowData.get(j));
            }
        }
    }

    /**
     * 讀取Excel文件第一頁
     * 
     * @param pathname 文件路徑名
     * @return 第一頁數據集合
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static List<List<Object>> readExcelFirstSheet(String pathname) throws IOException {
        File file = new File(pathname);
        return readExcelFirstSheet(file);

    }

    /**
     * 讀取Excel文件第一頁
     * 
     * @param file Excel文件
     * @return 第一頁數據集合
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static List<List<Object>> readExcelFirstSheet(File file) throws IOException {
        try (
                InputStream inputStream = new FileInputStream(file);
        ) {

            if (file.getName().endsWith(XLS)) {
                return readXlsFirstSheet(inputStream);
            }

            else if (file.getName().endsWith(XLSX)) {
                return readXlsxFirstSheet(inputStream);
            }

            else {
                throw new IOException("文件類型錯誤");
            }
        }

    }

    /**
     * 讀取xls格式Excel文件第一頁
     * 
     * @param inputStream Excel文件輸入流
     * @return 第一頁數據集合
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static List<List<Object>> readXlsFirstSheet(InputStream inputStream) throws IOException {
        Workbook workbook = new HSSFWorkbook(inputStream);
        return readExcelFirstSheet(workbook);
    }

    /**
     * 讀取xlsx格式Excel文件第一頁
     * 
     * @param inputStream Excel文件輸入流
     * @return 第一頁數據集合
     * @throws IOException 錯誤時拋出異常，由調用者處理
     */
    public static List<List<Object>> readXlsxFirstSheet(InputStream inputStream) throws IOException {
        Workbook workbook = new XSSFWorkbook(inputStream);
        return readExcelFirstSheet(workbook);
    }

    /**
     * 讀取Workbook第一頁
     * 
     * @param book Workbook對象
     * @return 第一頁數據集合
     */
    public static List<List<Object>> readExcelFirstSheet(Workbook book) {
        return readExcel(book, 0);
    }

    /**
     * 讀取指定頁面的Excel
     * 
     * @param book Workbook對象
     * @param page 頁碼
     * @return 指定頁面數據集合
     */
    public static List<List<Object>> readExcel(Workbook book, int page) {
        List<List<Object>> list = new ArrayList<>();
        Sheet sheet = book.getSheetAt(page);
        for (int i = 0; i <= sheet.getLastRowNum(); i++) {
            Row row = sheet.getRow(i);

            // 若是當前行爲空，則加入空，保持行號一致
            if (null == row) {
                list.add(null);
                continue;
            }

            List<Object> columns = new ArrayList<>();
            for (int j = 0; j < row.getLastCellNum(); j++) {
                Cell cell = row.getCell(j);
                columns.add(getValue(cell));
            }

            list.add(columns);
        }

        return list;
    }

    /**
     * 解析單元格中的值
     * 
     * @param cell 單元格
     * @return 單元格內的值
     */
    private static Object getValue(Cell cell) {
        if (null == cell) {
            return null;
        }
        Object value = null;
        switch (cell.getCellType()) {
        case BOOLEAN:
            value = cell.getBooleanCellValue();
            break;

        case NUMERIC:

            // 日期類型，轉換爲日期
            if (DateUtil.isCellDateFormatted(cell)) {
                value = cell.getDateCellValue();
            }

            // 數值類型
            else {

                // 默認返回double，建立BigDecimal返回準確值
                value = new BigDecimal(cell.getNumericCellValue());
            }
            break;

        default:
            value = cell.toString();
            break;
        }

        return value;
    }

    /**
     * 設置單元格值
     * 
     * @param cell 單元格
     * @param value 值
     */
    private static void setValue(Cell cell, Object value) {
        if (null == cell) {
            return;
        }

        if (null == value) {
            cell.setCellValue((String) null);
        }

        else if (value instanceof Boolean) {
            cell.setCellValue((Boolean) value);
        }

        else if (value instanceof Date) {
            cell.setCellValue(FORMAT.format((Date) value));
        }

        else if (value instanceof Double) {
            cell.setCellValue((Double) value);
        }

        else {
            cell.setCellValue(value.toString());
        }

    }

}

 

 

 

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