前面已經講過利用POI讀寫Excel，下面是一個用POI向Excel中插入圖片的例子。

官方文檔：
Images are part of the drawing support. To add an image just call createPicture() on the drawing patriarch. At the time of writing the following types are supported:
PNG
JPG
DIB
It is not currently possible to read existing images and it should be noted that any existing drawings may be erased once you add a image to a sheet.

// Create the drawing patriarch. This is the top level container for
// all shapes. This will clear out any existing shapes for that sheet.

通過HSSFPatriarch類createPicture方法的在指定的wb中的sheet創建圖片,它接受二個參數，第一個是HSSFClientAnchor，設定圖片的大小。

package com.poi.hssf.test;

import java.io.FileOutputStream;
import java.io.File;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

import java.awt.image.BufferedImage;
import javax.imageio.*;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFPatriarch;
import org.apache.poi.hssf.usermodel.HSSFClientAnchor;;

public class TestPOI {

??? public static void main(String[] args) {
??????????? FileOutputStream fileOut = null;
??????????? BufferedImage bufferImg =null;
??????????? BufferedImage bufferImg1 = null;
??????????? try{
?????????? ??? ?
????????? //先把讀進來的圖片放到一個ByteArrayOutputStream中，以便產生ByteArray
????????? ByteArrayOutputStream byteArrayOut = new ByteArrayOutputStream();
????????? ByteArrayOutputStream byteArrayOut1 = new ByteArrayOutputStream();
????????? bufferImg = ImageIO.read(new File("d:/PieChart.jpg"));
????????? bufferImg1 = ImageIO.read(new File("d:/fruitBarChart.jpg"));
????????? ImageIO.write(bufferImg,"jpg",byteArrayOut);
????????? ImageIO.write(bufferImg1,"jpg",byteArrayOut1);
???????? ?
??????? //創建一個工作薄
?? ??? ?HSSFWorkbook wb = new HSSFWorkbook();
?? ??? ?HSSFSheet sheet1 = wb.createSheet("new sheet");
?? ??? ?//HSSFRow row = sheet1.createRow(2);
?? ??? ?HSSFPatriarch patriarch = sheet1.createDrawingPatriarch();
?? ??? ?HSSFClientAnchor anchor = new HSSFClientAnchor(0,0,512,255,(short) 1,1,(short)10,20);
?? ??? ?HSSFClientAnchor anchor1 = new HSSFClientAnchor(0,0,512,255,(short) 2,30,(short)10,60);
?? ??? ?anchor1.setAnchorType(2);
?? ??? ?//插入圖片
?? ??? ?patriarch.createPicture(anchor , wb.addPicture(byteArrayOut.toByteArray(),HSSFWorkbook.PICTURE_TYPE_JPEG));
?? ??? ?patriarch.createPicture(anchor1 , wb.addPicture(byteArrayOut1.toByteArray(),HSSFWorkbook.PICTURE_TYPE_JPEG));
?? ??? ?
?? ??? ??? ?fileOut = new FileOutputStream("d:/workbook.xls");
?? ??? ??? ?//寫入excel文件
?? ??? ??? ?wb.write(fileOut);
?? ??? ??? ?fileOut.close();
?? ??? ?
?? ??? ???? }catch(IOException io){
?? ??? ???????????? io.printStackTrace();
?? ??? ???????????? System.out.println("io erorr :? "+ io.getMessage());
?? ??? ???? } finally
?? ??? ???? {
?? ??? ??? ??? ?if (fileOut != null)
?? ??? ??? ??? ?{
?? ??? ?????????????????? ?
?? ??? ??? ??? ??? ?try {
?? ??? ?????????????????????? fileOut.close();
?? ??? ????????????????? }
?? ??? ??? ??? ??? ?catch (IOException e)
?? ??? ??? ??? ??? ?{
??????????????????????????? // TODO Auto-generated catch block
??????????????????????????? e.printStackTrace();
?? ??? ????????????? }
?? ??? ??? ??? ?}
?? ??? ???? }
??? }
}