poi导出excel

Java使用poi组件导出excel报表，能导出excel报表的还可以使用jxl组件，但jxl想对于poi功能有限，jxl应该不能载excel插入浮动层图片，poi能很好的实现输出excel各种功能，介绍poi导出excel功能实现案例,算比较常用的功能实现以及导出excel需要注意的地方，采用的是poi-3.8-20120326.jar,poi-ooxml-3.8-20120326.jar,poi-scratchpad-3.8-20120326.jar

输出表格

poi输出excel最基本是输出table表格，下面是输出区域、总销售额(万元)、总利润(万元)简单的表格,
创建HSSFWorkbook 对象，用于将excel输出到输出流中

HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet = wb.createSheet("table");  //创建table工作薄
Object[][] datas = {{"区域", "总销售额(万元)", "总利润(万元)简单的表格"}, {"江苏省" , 9045,  2256}, {"广东省", 3000, 690}};
HSSFRow row;
HSSFCell cell;
for(int i = 0; i < datas.length; i++) {
    row = sheet.createRow(i);//创建表格行
    for(int j = 0; j < datas[i].length; j++) {
        cell = row.createCell(j);//根据表格行创建单元格
        cell.setCellValue(String.valueOf(datas[i][j]));
    }
}
wb.write(new FileOutputStream("/Users/mike/table.xls"));
              

设置表格行高、列宽

有时表格文本比较多，需要设置表格的列宽度，在设置表格的行高与列宽时一定在创建全部的HSSFRow与HSSFCell之后，
即整个表格创建完成之后去设置，因为在单元格合并的时候，合并之前设置的宽度单元格会比设置的宽度更宽。 sheet.setColumnWidth 设置列宽值需要转换为excel的宽度值，使用工具类：MSExcelUtil，excel宽度并不是像素需要转换

HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet = wb.createSheet("table");  //创建table工作薄
Object[][] datas = {{"区域", "总销售额(万元)", "总利润(万元)简单的表格"}, {"江苏省" , 9045,  2256}, {"广东省", 3000, 690}};
HSSFRow row;
HSSFCell cell;
for(int i = 0; i < datas.length; i++) {
    row = sheet.createRow(i);//创建表格行
    for(int j = 0; j < datas[i].length; j++) {
        cell = row.createCell(j);//根据表格行创建单元格
        cell.setCellValue(String.valueOf(datas[i][j]));
    }
}

//创建表格之后设置行高与列宽
for(int i = 0; i < datas.length; i++) {
    row = sheet.getRow(i);
    row.setHeightInPoints(30);//设置行高
}
for(int j = 0; j < datas[0].length; j++) {
    sheet.setColumnWidth(j, MSExcelUtil.pixel2WidthUnits(160)); //设置列宽
}
wb.write(new FileOutputStream("/Users/mike/table1.xls"));
                

设置excel单元格样式

单元格可以设置居左、居中、居右、上下居中、设置边框、设置边框颜色、设置单元格背景颜色等, excel设置单元格有一个HSSFCellStyle类可以设置样式，单元格颜色比较麻烦，excel颜色对应一个下标值，我们可以使用自定义颜色，但下标值从11开始，前1-10被poi已经使用，通过palette.setColorAtIndex方法将颜色与下标值对应，下面cellStyle.setFillForegroundColor(bgIndex)设置背景颜色时set 下标值并不是颜色Color，一个下标值如11不能被重复设置颜色，否则excel单元格显示的都是黑色，如下 背景颜色使用下标值bgIndex=11，边框颜色使用下标值bdIndex=12

short colorIndex = 10;
HSSFPalette palette = wb.getCustomPalette();//自定义颜色
Color rgb = Color.GREEN;
short bgIndex = colorIndex ++; //背景颜色下标值
palette.setColorAtIndex(bgIndex, (byte) rgb.getRed(), (byte) rgb.getGreen(), (byte) rgb.getBlue());
short bdIndex = colorIndex ++; //边框颜色下标值
rgb = Color.BLACK;
palette.setColorAtIndex(bdIndex, (byte) rgb.getRed(), (byte) rgb.getGreen(), (byte) rgb.getBlue());

for(int i = 0; i < datas.length; i++) {
    row = sheet.createRow(i);//创建表格行
    for(int j = 0; j < datas[i].length; j++) {
        cell = row.createCell(j);//根据表格行创建单元格
        cell.setCellValue(String.valueOf(datas[i][j]));

        HSSFCellStyle cellStyle = wb.createCellStyle();
        cellStyle.setFillForegroundColor(bgIndex); //bgIndex 背景颜色下标值
        cellStyle.setFillPattern(CellStyle.SOLID_FOREGROUND);

        cellStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
        //bdIndex 边框颜色下标值
        cellStyle.setBottomBorderColor(bdIndex);
        cellStyle.setLeftBorderColor(bdIndex);
        cellStyle.setRightBorderColor(bdIndex);
        cellStyle.setTopBorderColor(bdIndex);

        cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);

        cell.setCellStyle(cellStyle);
    }
}
                

单元格文本设置字体样式

单元格文本可设置字体大小、颜色、斜体、粗体、下划线等。

HSSFCellStyle cellStyle = wb.createCellStyle();

HSSFFont font = wb.createFont();
font.setItalic(true);
font.setUnderline(HSSFFont.U_SINGLE);
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
font.setFontHeightInPoints((short)14);
cellStyle.setFont(font);
                

合并单元格

sheet中可以类似html合并单元格,指定开始行(从0开始计算)、合并单元格最后行、开始列(从0开始)、 合并单元格最后列四个参数值

 CellRangeAddress region = new CellRangeAddress(0, // first row
        0, // last row
        0, // first column
        2 // last column
);
sheet.addMergedRegion(region);
                

单元格中加入图片

单元格中不仅是文本、数值、也可以加入图片，需要指定图片占用单元格开始行数、开始列数、末尾行数、末尾列数。 
支持png、jpeg、emf等

//加入图片
byte[] bt = FileUtils.readFileToByteArray(new File("/Users/mike/pie.png"));
int pictureIdx = wb.addPicture(bt, Workbook.PICTURE_TYPE_PNG);
CreationHelper helper = wb.getCreationHelper();
Drawing drawing = sheet.createDrawingPatriarch();
ClientAnchor anchor = helper.createClientAnchor();
anchor.setCol1(0); //图片开始列数
anchor.setRow1(4); //图片开始行数
anchor.setCol2(3); //图片结束列数
anchor.setRow2(25);//图片结束行数
drawing.createPicture(anchor, pictureIdx);
                

excel中插入浮动层图片类似html中div

excel中插入图片, poi导出excel似乎没有按绝对位置X、Y这样插入图片，可以行高和列宽计算X、Y值的大概的位置在哪个单元格中,
然后类似（6）中插入图片，只指定图片开始行数、开始列数，picture.resize()会使图片依据图片实际大小进行扩展。

//加入图片
int pictureIdx = wb.addPicture(bt, Workbook.PICTURE_TYPE_PNG);
CreationHelper helper = wb.getCreationHelper();
Drawing drawing = sheet.createDrawingPatriarch();
ClientAnchor anchor = helper.createClientAnchor();
anchor.setCol1(0); //图片开始列数
anchor.setRow1(4); //图片开始行数
Picture picture = drawing.createPicture(anchor, pictureIdx);
picture.resize();
                

单元格中画斜线

excel单元格中画斜线另一篇有详细介绍：poi excel斜线表头

长度转换MSExcelUtil

excel中单元格宽度和高度并不是像素值、ppt值，所以需要转换，MSExcelUtil是一个转换工具类

public class MSExcelUtil {

	public static final short EXCEL_COLUMN_WIDTH_FACTOR = 256;
	public static final int UNIT_OFFSET_LENGTH = 7;
	public static final int[] UNIT_OFFSET_MAP = new int[] { 0, 36, 73, 109, 146, 182, 219 };

	/**
	 * pixel units to excel width units(units of 1/256th of a character width)
	 *
	 * @param pxs
	 * @return
	 */
	public static short pixel2WidthUnits(int pxs) {
		short widthUnits = (short) (EXCEL_COLUMN_WIDTH_FACTOR * (pxs / UNIT_OFFSET_LENGTH));
		widthUnits += UNIT_OFFSET_MAP[(pxs % UNIT_OFFSET_LENGTH)];
		return widthUnits;
	}

	/**
	 * excel width units(units of 1/256th of a character width) to pixel units
	 *
	 * @param widthUnits
	 * @return
	 */
	public static int widthUnits2Pixel(int widthUnits) {
		int pixels = (widthUnits / EXCEL_COLUMN_WIDTH_FACTOR) * UNIT_OFFSET_LENGTH;
		int offsetWidthUnits = widthUnits % EXCEL_COLUMN_WIDTH_FACTOR;
		pixels += Math.round(offsetWidthUnits
				/ ((float) EXCEL_COLUMN_WIDTH_FACTOR / UNIT_OFFSET_LENGTH));

		return pixels;
	}
}
             

完整例子

poi导出excel源码

import java.awt.Color;
import java.io.File;
import java.io.FileOutputStream;

import org.apache.commons.io.FileUtils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFPalette;
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.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.ClientAnchor;
import org.apache.poi.ss.usermodel.CreationHelper;
import org.apache.poi.ss.usermodel.Drawing;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;

public final class TestExportExcel {

    public static void main(String[] args) throws Exception  {

        HSSFWorkbook wb = new HSSFWorkbook();
        HSSFSheet sheet = wb.createSheet("table");  //创建table工作薄
        Object[][] datas = {{"区域产品销售额","",""},{"区域", "总销售额(万元)", "总利润(万元)简单的表格"}, {"江苏省" , 9045,  2256}, {"广东省", 3000, 690}};
        HSSFRow row;
        HSSFCell cell;

        short colorIndex = 10;
        HSSFPalette palette = wb.getCustomPalette();
        Color rgb = Color.GREEN;
        short bgIndex = colorIndex ++;
        palette.setColorAtIndex(bgIndex, (byte) rgb.getRed(), (byte) rgb.getGreen(), (byte) rgb.getBlue());
        short bdIndex = colorIndex ++;
        rgb = Color.BLACK;
        palette.setColorAtIndex(bdIndex, (byte) rgb.getRed(), (byte) rgb.getGreen(), (byte) rgb.getBlue());

        for(int i = 0; i < datas.length; i++) {
            row = sheet.createRow(i);//创建表格行
            for(int j = 0; j < datas[i].length; j++) {
                cell = row.createCell(j);//根据表格行创建单元格
                cell.setCellValue(String.valueOf(datas[i][j]));

                HSSFCellStyle cellStyle = wb.createCellStyle();
                if(i == 0 || i == 1) {
                      cellStyle.setFillForegroundColor(bgIndex); //bgIndex 背景颜色下标值
                      cellStyle.setFillPattern(CellStyle.SOLID_FOREGROUND);
                }

                cellStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
                cellStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
                cellStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
                cellStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
                //bdIndex 边框颜色下标值
                cellStyle.setBottomBorderColor(bdIndex);
                cellStyle.setLeftBorderColor(bdIndex);
                cellStyle.setRightBorderColor(bdIndex);
                cellStyle.setTopBorderColor(bdIndex);

                cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
                cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);

                if(i == datas.length - 1 && j == datas[0].length - 1) {
                    HSSFFont font = wb.createFont();
                    font.setItalic(true);
                    font.setUnderline(HSSFFont.U_SINGLE);
                    font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
                    font.setFontHeightInPoints((short)14);
                    cellStyle.setFont(font);
                }
                cell.setCellStyle(cellStyle);
            }
        }

        //加入图片
        byte[] bt = FileUtils.readFileToByteArray(new File("/Users/mike/pie.png"));
        int pictureIdx = wb.addPicture(bt, Workbook.PICTURE_TYPE_PNG);
        CreationHelper helper = wb.getCreationHelper();
        Drawing drawing = sheet.createDrawingPatriarch();
        ClientAnchor anchor = helper.createClientAnchor();
        anchor.setDx1(MSExcelUtil.pixel2WidthUnits(60));
        anchor.setDy1(MSExcelUtil.pixel2WidthUnits(60));
        //anchor.setCol1(0);
        //anchor.setRow1(4);
       // anchor.setCol2(3);
       // anchor.setRow2(25);
        drawing.createPicture(anchor, pictureIdx);

        //合并单元格
        CellRangeAddress region = new CellRangeAddress(0, // first row
                0, // last row
                0, // first column
                2 // last column
        );
        sheet.addMergedRegion(region);

        //创建表格之后设置行高与列宽
        for(int i = 0; i < datas.length; i++) {
            row = sheet.getRow(i);
            row.setHeightInPoints(30);
        }
        for(int j = 0; j < datas[0].length; j++) {
            sheet.setColumnWidth(j, MSExcelUtil.pixel2WidthUnits(160));
        }
        wb.write(new FileOutputStream("/Users/mike/table6.xls"));
    }
}

转自：http://www.anyrt.com/blog/list/poiexcel.html