java POI创建Excel示例（xslx和xsl区别 ）

Java用来处理office类库有很多，其中POI就是比较出名的一个，它是apache的类库，现在版本到了3.10，也就是2014年2月8号这个版本。

在处理PPT，Excel和Word前，需要导入以前几个jar包：

dom4j-1.7-20060614.jar

log4j-1.2.13.jar

poi-3.7-20101029.jar

poi-ooxml-3.7-20101029.jar

poi-ooxml-schemas-3.7-20101029.jar

本文主要简介下java poi处理Excel，

2003版本的.xls一张sheet表允许存2^16 ＝ 次方行数据，2^8 = 256列数据，

2007版本以上的.xlsx一张sheet表允许存的数据就更大了，是百万级别的。行： 2^20 = 1048576; 列：2^14 = 16384 行。

以下代码简单操作了excel文件。 

 package com.caoyuanzhanlang.excelhandle;

 import java.io.File;
 import java.io.FileOutputStream;

 import org.apache.poi.hssf.util.HSSFColor;
 import org.apache.poi.ss.usermodel.Cell;
 import org.apache.poi.ss.usermodel.CellStyle;
 import org.apache.poi.ss.usermodel.Font;
 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 NewExcel {

     private String excelPath = "data.xlsx";

     public static void main(String[] args) throws Exception{
         NewExcel excel = new NewExcel();
         if(excel.createExcelFile()) {
             System.out.println("data.xlsx is created successfully.");
         }
     }
     public boolean createExcelFile() {
         boolean isCreateSuccess = false;
         Workbook workbook = null;
         try {
             // XSSFWork used for .xslx (>= 2007), HSSWorkbook for 03 .xsl
             workbook = new XSSFWorkbook();//HSSFWorkbook();//WorkbookFactory.create(inputStream);
         }catch(Exception e) {
             System.out.println("It cause Error on CREATING excel workbook: ");
             e.printStackTrace();
         }
         if(workbook != null) {
             Sheet sheet = workbook.createSheet("testdata");
             Row row0 = sheet.createRow(0);
             for(int i = 0; i < 11; i++) {
                 Cell cell_1 = row0.createCell(i, Cell.CELL_TYPE_STRING);
                 CellStyle style = getStyle(workbook);
                 cell_1.setCellStyle(style);
                 cell_1.setCellValue("HELLO" + i + "Column");
                 sheet.autoSizeColumn(i);
             }
             for (int rowNum = 1; rowNum < 200; rowNum++) {
                 Row row = sheet.createRow(rowNum);
                 for(int i = 0; i < 11; i++) {
                     Cell cell = row.createCell(i, Cell.CELL_TYPE_STRING);
                     cell.setCellValue("cell" + String.valueOf(rowNum+1) + String.valueOf(i+1));
                 }
             }
             try {
                 FileOutputStream outputStream = new FileOutputStream(excelPath);
                 workbook.write(outputStream);
                 outputStream.flush();
                 outputStream.close();
                 isCreateSuccess = true;
             } catch (Exception e) {
                 System.out.println("It cause Error on WRITTING excel workbook: ");
                 e.printStackTrace();
             }
         }
         File sss = new File(excelPath);
         System.out.println(sss.getAbsolutePath());
         return isCreateSuccess;
     }
     private CellStyle getStyle(Workbook workbook){
         CellStyle style = workbook.createCellStyle();
         style.setAlignment(CellStyle.ALIGN_CENTER);
         style.setVerticalAlignment(CellStyle.VERTICAL_CENTER);
         // 设置单元格字体
         Font headerFont = workbook.createFont(); // 字体
         headerFont.setFontHeightInPoints((short)14);
         headerFont.setColor(HSSFColor.RED.index);
         headerFont.setFontName("宋体");
         style.setFont(headerFont);
         style.setWrapText(true);

         // 设置单元格边框及颜色
         style.setBorderBottom((short)1);
         style.setBorderLeft((short)1);
         style.setBorderRight((short)1);
         style.setBorderTop((short)1);
         style.setWrapText(true);
         return style;
     }
     public String getExcelPath() {
         return this.excelPath;
     }

     public void setExcelPath(String excelPath) {
         this.excelPath = excelPath;
     }
 }