POI官方网址：http://poi.apache.org/
POI的功能实在很强大，而且是apache的子项目，它下面又包含一些Component，比如处理Excel XLS，PowerPoint PPT，Word DOC，Outlook MSG，Excel XLSX等，下面就简单讲下poi处理excel的一些内容。
下面的jar包来源于当前最新的poi 3.6版本。
1.poi来生成excel
package com.test.poi;
import java.io.FileOutputStream;
import java.util.Date;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFHyperlink;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.util.CellRangeAddress;
public class WriteExcel {
public static void main(String[] args) throws Exception {
// 创建Excel的工作书册 Workbook,对应到一个excel文档
HSSFWorkbook wb = new HSSFWorkbook();
// 创建Excel的工作sheet,对应到一个excel文档的tab
HSSFSheet sheet = wb.createSheet("sheet1");
// 设置excel每列宽度
sheet.setColumnWidth(0, 4000);
sheet.setColumnWidth(1, 3500);
// 创建字体样式
HSSFFont font = wb.createFont();
font.setFontName("Verdana");
font.setBoldweight((short) 100);
font.setFontHeight((short) 300);
font.setColor(HSSFColor.BLUE.index);
// 创建单元格样式
HSSFCellStyle style = wb.createCellStyle();
style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
style.setFillForegroundColor(HSSFColor.LIGHT_TURQUOISE.index);
style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
// 设置边框
style.setBottomBorderColor(HSSFColor.RED.index);
style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
style.setBorderRight(HSSFCellStyle.BORDER_THIN);
style.setBorderTop(HSSFCellStyle.BORDER_THIN);
style.setFont(font);// 设置字体
// 创建Excel的sheet的一行
HSSFRow row = sheet.createRow(0);
row.setHeight((short) 500);// 设定行的高度
// 创建一个Excel的单元格
HSSFCell cell = row.createCell(0);
// 合并单元格(startRow，endRow，startColumn，endColumn)
sheet.addMergedRegion(new CellRangeAddress(0, 0, 0, 2));
// 给Excel的单元格设置样式和赋值
cell.setCellStyle(style);
cell.setCellValue("hello world");
// 设置单元格内容格式
HSSFCellStyle style1 = wb.createCellStyle();
style1.setDataFormat(HSSFDataFormat.getBuiltinFormat("h:mm:ss"));
style1.setWrapText(true);// 自动换行
row = sheet.createRow(1);
// 设置单元格的样式格式
cell = row.createCell(0);
cell.setCellStyle(style1);
cell.setCellValue(new Date());
// 创建超链接
HSSFHyperlink link = new HSSFHyperlink(HSSFHyperlink.LINK_URL);
link.setAddress("http://www.baidu.com");
cell = row.createCell(1);
cell.setCellValue("百度");
cell.setHyperlink(link);// 设定单元格的链接
FileOutputStream os = new FileOutputStream("e:\\workbook.xls");
wb.write(os);
os.close();
}
}
2.poi读取excel
package com.test.poi;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import org.apache.poi.hssf.extractor.ExcelExtractor;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
public class ReadExcel {
public static void main(String[] args) throws Exception {
HSSFWorkbook wb = null;
POIFSFileSystem fs = null;
try {
fs = new POIFSFileSystem(new FileInputStream("e:\\workbook.xls"));
wb = new HSSFWorkbook(fs);
} catch (IOException e) {
e.printStackTrace();
}
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row = sheet.getRow(0);
HSSFCell cell = row.getCell(0);
String msg = cell.getStringCellValue();
System.out.println(msg);
}
public static void method2() throws Exception {
InputStream is = new FileInputStream("e:\\workbook.xls");
HSSFWorkbook wb = new HSSFWorkbook(new POIFSFileSystem(is));
ExcelExtractor extractor = new ExcelExtractor(wb);
extractor.setIncludeSheetNames(false);
extractor.setFormulasNotResults(false);
extractor.setIncludeCellComments(true);
String text = extractor.getText();
System.out.println(text);
}
public static void method3() throws Exception {
HSSFWorkbook wb = new HSSFWorkbook(new FileInputStream("e:\\workbook.xls"));
HSSFSheet sheet = wb.getSheetAt(0);
for (Iterator<Row> iter = (Iterator<Row>) sheet.rowIterator(); iter.hasNext();) {
Row row = iter.next();
for (Iterator<Cell> iter2 = (Iterator<Cell>) row.cellIterator(); iter2.hasNext();) {
Cell cell = iter2.next();
String content = cell.getStringCellValue();// 除非是sring类型，否则这样迭代读取会有错误
System.out.println(content);
}
}
}
}
注：HSSFWorkbook，XSSFWorkbook的区别：前者是解析出来excel 2007 以前版本的，后缀名为xls的，后者是解析excel 2007 版的，后缀名为xlsx。
在实际应用中，要对excel文件进行判断，该用哪个workbook来对其进行解析处理，而且，通常把这些方法都做了相应封装，使其更面向对象，上例只是main方法的简单示例而已，仅供参考！
