Poi读写Excel文件

Apache的Poi读写Excel比较强大，对xlsx和xls都能够支持，当然也支持更多的设置，下面是Poi的demo。

详细查看poi的api：http://poi.apache.org/spreadsheet/quick-guide.html

一、使用的包

    maven的相关依赖坐标

    

  <dependency>
			<groupId>org.apache.poi</groupId>
			<artifactId>poi</artifactId>
			<version>3.10-FINAL</version>
		</dependency>

		<dependency>
			<groupId>org.apache.poi</groupId>
			<artifactId>poi-ooxml</artifactId>
			<version>3.10-FINAL</version>
		</dependency>

二、Poi的demo

package org.andy.excel;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Calendar;
import java.util.Date;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.CreationHelper;
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.ss.usermodel.WorkbookFactory;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.junit.Test;

public class PoiExcelTest {

	public static void readExcel(String filePath) {
		if (null != filePath && !"".equals(filePath.trim())) {
			Workbook workbook = null;
			InputStream inputStream = null;

			try {
				inputStream = new FileInputStream(filePath);
				workbook = WorkbookFactory.create(inputStream); //使用WorkbookFactory创建，会安装xls或xlsx
				Sheet sheet = workbook.getSheetAt(0);
				if (null != sheet) {
					for (Row row : sheet) {
						
						for (Cell cell : row) {

							switch (cell.getCellType()) {// 判断内容类型
							case Cell.CELL_TYPE_STRING:// string类型
								System.out.print(cell.getRichStringCellValue()
										.getString());
								break;
							case Cell.CELL_TYPE_NUMERIC: //数字类型
								if (DateUtil.isCellDateFormatted(cell)) {//判断是否是日期
									System.out.print(cell.getDateCellValue());
								} else {
									System.out
											.print(cell.getNumericCellValue());
								}
								break;
							case Cell.CELL_TYPE_BOOLEAN: //布尔类型
								System.out.print(cell.getBooleanCellValue());
								break;
							case Cell.CELL_TYPE_FORMULA: //公式
								System.out.print(cell.getCellFormula());
								break;
							default:
								System.out.print("");
							}
							System.out.print("  ");
						}
						System.out.println();
					}
				}

			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				if (null != inputStream) {
					try {
						inputStream.close();
						inputStream = null;
					} catch (Exception e) {
						e.printStackTrace();
					}
				}

			}

		}

	}

	public void writeExcel(String filePath) {

		if (null != filePath && !"".equals(filePath.trim())) {
			Workbook workbook = null;
			
			//根据不同的excel格式创建workbook
			if (filePath.trim().toLowerCase().endsWith(".xls")) {
				workbook = new HSSFWorkbook();
			} else if (filePath.trim().toLowerCase().endsWith(".xlsx")) {
				workbook = new XSSFWorkbook();
			} else {
				return;
			}

			OutputStream outputStream = null;
			try {
				outputStream = new FileOutputStream(filePath);
				CreationHelper createHelper = workbook.getCreationHelper();
				Sheet sheet = workbook.createSheet();
				
				Row row = sheet.createRow(0);
				row.createCell(0).setCellValue("is string");
				//string类型
				//设置cell的样式
				CellStyle cellStyle = workbook.createCellStyle();
				cellStyle.setDataFormat(createHelper.createDataFormat()
						.getFormat("yyyy-MM-dd HH:mm:ss")); 
				
				Cell cell = row.createCell(1);
				cell.setCellStyle(cellStyle);
				cell.setCellValue(new Date());
				
				//Calendar 
				row.createCell(2).setCellValue(Calendar.getInstance());
				//布尔类
				row.createCell(3).setCellValue(true);
				//数字类型
				row.createCell(4).setCellValue(200);

				workbook.write(outputStream);

			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				if (null != outputStream) {
					try {
						outputStream.close();
					} catch (Exception e) {
						e.printStackTrace();
					}
				}
			}

		}
	}

	@Test
	public void read() {
	    readExcel("c:\\andy.xlsx");
	}

	@Test
	public void write() {
		writeExcel("c:\\andy.xlsx");
	}
}