Java POI读取excel的例子

<span style="font-size:12px;">package com.excel;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;

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.ss.usermodel.WorkbookFactory;

import com.yfli.util.User;

public class TestExcel {
public static void main(String[] args) throws Exception {
//导入
importExcel("F:\\xls\\test_import.xls");

//导出
File modelFile = new File("F:\\xls\\test_export_model.xls");
Calendar now = Calendar.getInstance();
String dbfFileName = "sfData_" + now.get(Calendar.YEAR)
+ (now.get(Calendar.MONTH) + 1) + ""
+ now.get(Calendar.DAY_OF_MONTH)
+ now.get(Calendar.HOUR_OF_DAY) + now.get(Calendar.MINUTE)
+ now.get(Calendar.MINUTE) + ".xls";

String directoryPath = "F:\\xls\\";
String filePath = "F:\\xls\\" + dbfFileName;
File directory = new File(directoryPath);// 目标文件夹
if (!directory.exists()) {
directory.mkdirs();// 创建目标目录
}
File outputFile = new File(filePath);
if (!outputFile.exists() || outputFile.isDirectory()) {
outputFile.createNewFile();
}
exportExcelContent(modelFile, outputFile, getUserList());
}

public static void importExcel(String file) {
try {
FileInputStream fis = new FileInputStream(file);
Workbook wb = WorkbookFactory.create(fis);

int sheetCount = wb.getNumberOfSheets(); // 得到excel工作表的总数
for (int n = 0; n < sheetCount; n++) {
Sheet sheet = wb.getSheetAt(n); // 得到Excel工作表对象
int rowNum = sheet.getPhysicalNumberOfRows();// 得到行的总数
if (rowNum == 0) {
continue;
}
String[] title = readExcelHead(sheet);
List<User> users = readExcelContent(sheet, title);
for (User user : users) {
System.out.println(user.getName() + "---" + user.getSex()
+ "---" + user.getBirthday() + "---"
+ user.getAge());
}
}
} catch (Exception ex) {
ex.printStackTrace();
}
}

/**
* 读取Excel表头
*/
public static String[] readExcelHead(Sheet sheet) {
Row row = sheet.getRow(0);
int colNum = row.getPhysicalNumberOfCells(); // 标题总列数
String[] title = new String[colNum];
for (int i = 0; i < colNum; i++) {
title[i] = getStringCellValue(row.getCell(i));
}
return title;
}

public static List<User> readExcelContent(Sheet sheet, String[] title)
throws Exception {
int rowNum = sheet.getPhysicalNumberOfRows();// 得到行的总数
Row row = sheet.getRow(0);
int colNum = row.getPhysicalNumberOfCells(); // 标题总列数

List<User> content = new ArrayList<User>();
for (int i = 1; i < rowNum; i++) {
Row rows = sheet.getRow(i);
User user = new User();
for (int j = 0; j < colNum; j++) {
if (title[j].toString().equals("姓名")) {
user.setName(getStringCellValue(rows.getCell(j)));
}
if (title[j].toString().equals("性别")) {
user.setSex(getStringCellValue(rows.getCell(j)));
}
if (title[j].toString().equals("出生日期")) {
user.setBirthday(getStringCellValue(rows.getCell(j)));
}
if (title[j].toString().equals("年龄")) {
user.setAge(getStringCellValue(rows.getCell(j)));
}
}
content.add(user);
}
return content;
}

/**
* 导出数据到excel中
*
* @param outputFile
*            导出excel文件
* @param modelFile
*            导出excel模板（test_model.xlsx）
*/
public static void exportExcelContent(File modelFile, File outputFile,
List<User> users) {
InputStream inp = null;
Workbook wb = null;
try {
inp = new FileInputStream(modelFile);
wb = WorkbookFactory.create(inp); // 读取导出excel模板
Sheet sheet = wb.getSheetAt(0);
String[] title = readExcelHead(sheet);

// 生成导出数据
int startRow = 1;
for (int i = 0; i < users.size(); i++) {
User user = users.get(i);
Row row = sheet.createRow(startRow++);
for (int j = 0; j < title.length; j++) {
String titleName = title[j];
Cell cell = row.createCell(j);
cell.setCellType(Cell.CELL_TYPE_STRING);
if (titleName.equals("姓名")) {
cell.setCellValue(user.getName());
}
if (titleName.equals("性别")) {
cell.setCellValue(user.getSex());
}
if (titleName.equals("出生日期")) {
cell.setCellValue(user.getBirthday());
}
if (titleName.equals("年龄")) {
cell.setCellValue(user.getAge());
}
}
}

// 导出到文件中
FileOutputStream fileOut = new FileOutputStream(outputFile);
wb.write(fileOut);
fileOut.close();
} catch (Exception ex) {
ex.printStackTrace();
}
}

/**
* 获取单元格数据内容为字符串类型的数据
*
* @param cell
*            Excel单元格
* @return String 单元格数据内容
*/
private static String getStringCellValue(Cell cell) {
String strCell = "";
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
strCell = cell.getStringCellValue();
break;
case Cell.CELL_TYPE_NUMERIC:
if(DateUtil.isCellDateFormatted(cell)) {
strCell = sdf.format(cell.getDateCellValue());
}else {
strCell = String.valueOf(cell.getNumericCellValue());
}
break;
case Cell.CELL_TYPE_BOOLEAN:
strCell = String.valueOf(cell.getBooleanCellValue());
break;
case Cell.CELL_TYPE_BLANK:
strCell = "";
break;
case Cell.CELL_TYPE_FORMULA:
strCell = String.valueOf(cell.getNumericCellValue());
break;
default:
strCell = "";
break;
}
if (strCell.equals("") || strCell == null) {
return "";
}
if (cell == null) {
return "";
}
return strCell;
}

private static List<User> getUserList() {
List<User> users = new ArrayList<User>();
User user = new User();
user.setName("张三");
user.setSex("男");
user.setBirthday("2013-12-01");
user.setAge("22");
users.add(user);

user = new User();
user.setName("李四");
user.setSex("男");
user.setBirthday("2013-12-02");
user.setAge("23");
users.add(user);
return users;
}
}
</span>

<span style="font-size:12px;">package com.yfli.util;

public class User {
public String name;
public String sex;
public String birthday;
public String age;

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getSex() {
return sex;
}

public void setSex(String sex) {
this.sex = sex;
}

public String getBirthday() {
return birthday;
}

public void setBirthday(String birthday) {
this.birthday = birthday;
}

public String getAge() {
return age;
}

public void setAge(String age) {
this.age = age;
}

}
</span>