<dependencies>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.16</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.14</version>
</dependency>
</dependencies>
import java.io.*;
import java.util.*;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
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;
public class ExcelUtil {
public static List<List<String>> readExcel(String filePath) {
List<List<String>> dataLst = null;
InputStream is = null;
try {
//验证文件是否合法
if (!validateExcel(filePath)) {
return null;
}
// 判断文件的类型，是2003还是2007
boolean isExcel2003 = true;
if (isExcel2007(filePath)) {
isExcel2003 = false;
}
// 调用本类提供的根据流读取的方法
File file = new File(filePath);
is = new FileInputStream(file);
dataLst = read(is, isExcel2003);
} catch (Exception ex) {
ex.printStackTrace();
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
is = null;
e.printStackTrace();
}
}
}
return dataLst;
}
private static List<List<String>> read(InputStream inputStream, boolean isExcel2003) {
List<List<String>> dataLst = null;
try {
//根据版本选择创建Workbook的方式
Workbook wb = null;
if (isExcel2003) {
wb = new HSSFWorkbook(inputStream);
} else {
wb = new XSSFWorkbook(inputStream);
}
dataLst = read(wb);
} catch (IOException e) {
e.printStackTrace();
}
return dataLst;
}
private static List<List<String>> read(Workbook wb) {
int totalRows = 0;
int totalCells = 0;
List<List<String>> dataLst = new ArrayList<List<String>>();
// 得到第一个shell
Sheet sheet = wb.getSheetAt(0);
// 得到Excel的行数
totalRows = sheet.getPhysicalNumberOfRows();
// 得到Excel的列数
if (totalRows >= 1 && sheet.getRow(0) != null) {
totalCells = sheet.getRow(0).getPhysicalNumberOfCells();
}
//遍历行
for (int r = 0; r < totalRows; r++) {
Row row = sheet.getRow(r);
if (row == null) {
continue;
}
List<String> rowLst = new ArrayList<String>();
//遍历列
for (int c = 0; c < totalCells; c++) {
Cell cell = row.getCell(c);
String cellValue = "";
if (null != cell) {
// 以下是判断数据的类型
switch (cell.getCellType()) {
case HSSFCell.CELL_TYPE_NUMERIC: // 数字
cellValue = cell.getNumericCellValue() + "";
break;
case HSSFCell.CELL_TYPE_STRING: // 字符串
cellValue = cell.getStringCellValue();
break;
case HSSFCell.CELL_TYPE_BOOLEAN: // Boolean
cellValue = cell.getBooleanCellValue() + "";
break;
case HSSFCell.CELL_TYPE_FORMULA: // 公式
cellValue = cell.getCellFormula() + "";
break;
case HSSFCell.CELL_TYPE_BLANK: // 空值
cellValue = "";
break;
case HSSFCell.CELL_TYPE_ERROR: // 故障
cellValue = "非法字符";
break;
default:
cellValue = "未知类型";
break;
}
}
rowLst.add(cellValue);
}
// 保存第r行的第c列
dataLst.add(rowLst);
}
return dataLst;
}
private static boolean validateExcel(String filePath) {
// 检查文件名是否为空或者是否是Excel格式的文件
if (filePath == null || !(isExcel2003(filePath) || isExcel2007(filePath))) {
return false;
}
// 检查文件是否存在
File file = new File(filePath);
if (file == null || !file.exists()) {
return false;
}
return true;
}
private static boolean isExcel2003(String filePath) {
return filePath.matches("^.+\.(?i)(xls)$");
}
private static boolean isExcel2007(String filePath) {
return filePath.matches("^.+\.(?i)(xlsx)$");
}
public static void writeExcel(List<List<String>> dataList, String finalXlsxPath){
OutputStream out = null;
try {
// 读取Excel文档
File finalXlsxFile = new File(finalXlsxPath);
Workbook workBook = getWorkbok(finalXlsxFile);
// sheet 对应一个工作页
Sheet sheet = workBook.getSheetAt(0);
//删除原有数据，除了属性列
int rowNumber = sheet.getLastRowNum();
for (int i = 1; i <= rowNumber; i++) {
Row row = sheet.getRow(i);
sheet.removeRow(row);
}
// 创建文件输出流，输出电子表格：这个必须有，否则你在sheet上做的任何操作都不会有效
out = new FileOutputStream(finalXlsxPath);
workBook.write(out);
//写一行
for (int j = 0; j < dataList.size(); j++) {
Row row = sheet.createRow(j);
//写一列
List<String> datas = dataList.get(j);
for (int k=0; k<datas.size(); k++) {
row.createCell(k).setCellValue(datas.get(k));
}
}
// 创建文件输出流，准备输出电子表格：这个必须有，否则你在sheet上做的任何操作都不会有效
out = new FileOutputStream(finalXlsxPath);
workBook.write(out);
System.out.println("数据导出成功");
} catch (Exception e) {
System.out.println("请创建一个空文件");
e.printStackTrace();
} finally{
try {
if(out != null){
out.flush();
out.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
private static final String EXCEL_XLS = "xls";
private static final String EXCEL_XLSX = "xlsx";
private static Workbook getWorkbok(File file) throws IOException{
Workbook wb = null;
FileInputStream in = new FileInputStream(file);
if(file.getName().endsWith(EXCEL_XLS)){ //Excel 2003
wb = new HSSFWorkbook(in);
}else if(file.getName().endsWith(EXCEL_XLSX)){ // Excel 2007/2010
wb = new XSSFWorkbook(in);
}
return wb;
}
}
import java.util.ArrayList;
import java.util.List;
public class Test {
public static void main(String[] args) {
List<List<String>> resultList = ExcelUtil.readExcel("H:/data.xlsx");
if (resultList != null) {
for (int i = 0; i < resultList.size(); i++) {
System.out.print("第" + (i) + "行");
List<String> cellList = resultList.get(i);
for (int j = 0; j < cellList.size(); j++) {
System.out.print(" " + cellList.get(j));
}
System.out.println();
}
}
//把读取的结果在写回去
ExcelUtil.writeExcel(resultList, "H:/result.xlsx");
}
}