JAVA EXCEL API简介

Java Excel是一开放源码项目，通过它Java开发人员可以读取Excel文件的内容、创建新的Excel文件、更新已经存在的Excel文件。使用该API非Windows操作系统也可以通过纯Java应用来处理Excel数据表。因为是使用Java编写的，所以我们在Web应用中可以通过JSP、Servlet来调用API实现对Excel数据表的访问。

提供以下功能：

• 从Excel 95、97、2000等格式的文件中读取数据；
• 读取Excel公式（可以读取Excel 97以后的公式）；
• 生成Excel数据表（格式为Excel 97）；
• 支持字体、数字、日期的格式化；
• 支持单元格的阴影操作，以及颜色操作；
• 修改已经存在的数据表；
• 能够读取图表信息

1.应用示例：
包括从Excel读取数据,生成新的Excel，以及修改Excel
package common.util;

import jxl.*;
import jxl.format.UnderlineStyle;
import jxl.write.*;
import jxl.write.Number;
import jxl.write.Boolean;

import java.io.*;

/**
 * Created by IntelliJ IDEA.
 * User: xl
 * Date: 2005-7-17
 * Time: 9:33:22
 * To change this template use File | Settings | File Templates.
 */
public class ExcelHandle
{
    public ExcelHandle()
    {
    }

    /**
     * 读取Excel
     *
     * @param filePath
     */
    public static void readExcel(String filePath)
    {
        try
        {
            InputStream is = new FileInputStream(filePath);
            Workbook rwb = Workbook.getWorkbook(is);
            //Sheet st = rwb.getSheet("0")这里有两种方法获取sheet表,1为名字，而为下标，从0开始
            Sheet st = rwb.getSheet("original");
            Cell c00 = st.getCell(0,0);
            //通用的获取cell值的方式,返回字符串
            String strc00 = c00.getContents();
            //获得cell具体类型值的方式
            if(c00.getType() == CellType.LABEL)
            {
                LabelCell labelc00 = (LabelCell)c00;
                strc00 = labelc00.getString();
            }
            //输出
            System.out.println(strc00);
            //关闭
            rwb.close();
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 输出Excel
     *
     * @param os
     */
    public static void writeExcel(OutputStream os)
    {
        try
        {
            /**
             * 只能通过API提供的工厂方法来创建Workbook，而不能使用WritableWorkbook的构造函数，
             * 因为类WritableWorkbook的构造函数为protected类型
             * method(1)直接从目标文件中读取WritableWorkbook wwb = Workbook.createWorkbook(new File(targetfile));
             * method(2)如下实例所示 将WritableWorkbook直接写入到输出流

             */
            WritableWorkbook wwb = Workbook.createWorkbook(os);
            //创建Excel工作表 指定名称和位置
            WritableSheet ws = wwb.createSheet("Test Sheet 1",0);

            //**************往工作表中添加数据*****************

            //1.添加Label对象
            Label label = new Label(0,0,"this is a label test");
            ws.addCell(label);

            //添加带有字型Formatting对象
            WritableFont wf = new WritableFont(WritableFont.TIMES,18,WritableFont.BOLD,true);
            WritableCellFormat wcf = new WritableCellFormat(wf);
            Label labelcf = new Label(1,0,"this is a label test",wcf);
            ws.addCell(labelcf);

            //添加带有字体颜色的Formatting对象
            WritableFont wfc = new WritableFont(WritableFont.ARIAL,10,WritableFont.NO_BOLD,false,
                    UnderlineStyle.NO_UNDERLINE,jxl.format.Colour.RED);
            WritableCellFormat wcfFC = new WritableCellFormat(wfc);
            Label labelCF = new Label(1,0,"This is a Label Cell",wcfFC);
            ws.addCell(labelCF);

            //2.添加Number对象
            Number labelN = new Number(0,1,3.1415926);
            ws.addCell(labelN);

            //添加带有formatting的Number对象
            NumberFormat nf = new NumberFormat("#.##");
            WritableCellFormat wcfN = new WritableCellFormat(nf);
            Number labelNF = new jxl.write.Number(1,1,3.1415926,wcfN);
            ws.addCell(labelNF);

            //3.添加Boolean对象
            Boolean labelB = new jxl.write.Boolean(0,2,false);
            ws.addCell(labelB);

            //4.添加DateTime对象
            jxl.write.DateTime labelDT = new jxl.write.DateTime(0,3,new java.util.Date());
            ws.addCell(labelDT);

            //添加带有formatting的DateFormat对象
            DateFormat df = new DateFormat("dd MM yyyy hh:mm:ss");
            WritableCellFormat wcfDF = new WritableCellFormat(df);
            DateTime labelDTF = new DateTime(1,3,new java.util.Date(),wcfDF);
            ws.addCell(labelDTF);

            //添加图片对象,jxl只支持png格式图片
            File image = new File("f:\\2.png");
            WritableImage wimage = new WritableImage(0,1,2,2,image);//0,1分别代表x,y.2,2代表宽和高占的单元格数
            ws.addImage(wimage);
            //写入工作表
            wwb.write();
            wwb.close();
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 拷贝后,进行修改,其中file1为被copy对象，file2为修改后创建的对象
     * 尽单元格原有的格式化修饰是不能去掉的，我们还是可以将新的单元格修饰加上去，
     * 以使单元格的内容以不同的形式表现
     * @param file1
     * @param file2
     */
    public static void modifyExcel(File file1,File file2)
    {
        try
        {
            Workbook rwb = Workbook.getWorkbook(file1);
            WritableWorkbook wwb = Workbook.createWorkbook(file2,rwb);//copy
            WritableSheet ws = wwb.getSheet(0);
            WritableCell wc = ws.getWritableCell(0,0);
            //判断单元格的类型,做出相应的转换
            if(wc.getType == CellType.LABEL)
            {
                Label label = (Label)wc;
                label.setString("The value has been modified");
            }
            wwb.write();
            wwb.close();
            rwb.close();
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }

    //测试
    public static void main(String[] args)
    {
        try
        {
            //读Excel
            ExcelHandle.readExcel("f:/testRead.xls");
            //输出Excel
            File fileWrite = new File("f:/testWrite.xls");
            fileWrite.createNewFile();
            OutputStream os = new FileOutputStream(fileWrite);
            ExcelHandle.writeExcel(os);
            //修改Excel
            ExcelHandle.modifyExcel(new file(""),new File(""));
        }
        catch(Exception e)
        {
           e.printStackTrace();
        }
    }
}

2.在jsp中做相关测试，创建一个writeExcel.jsp
<%
response.reset();//清除Buffer
response.setContentType("application/vnd.ms-excel");
File fileWrite = new File("f:/testWrite.xls");
fileWrite.createNewFile();
new FileOutputStream(fileWrite);
ExcelHandle.writeExcel(new FileOutputStream(fileWrite));
%>
在IE中浏览writeExcel.jsp就可以动态生成Excel文档了，其中response.setContentType("application/vnd.ms-excel");语句必须要，才能确保不乱码，在jsp中输入<%@page contentType="application/vnd.ms-excel;charset=GBK"%>不行。