Java Excel导出

Maven配置

<dependency>            <groupId>org.apache.poi</groupId>            <artifactId>poi</artifactId>            <version>3.7</version>        </dependency>

jar下载地址http://poi.apache.org/download.html

Java代码

package com.mk.util;import org.apache.poi.hssf.usermodel.*;import org.apache.poi.hssf.util.HSSFColor;import org.apache.poi.hssf.util.Region;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.text.DateFormat;import java.text.SimpleDateFormat;import java.util.List;import java.util.Set;public class ExcelUtil {      /**     * 导出Excel     *     * @param list      * @return excel的字节数组     */    public static byte[] exportLogs(List<Log> list) {        if (list == null) {            return null;        }        try {            HSSFWorkbook wb = new HSSFWorkbook();            int s=0;            for (int i = 0; s < list.size();i++,s = i * MAX_ROWS ) {                createOnePage(wb, list, s, i);            }            //先写到字节数组，在从字节数组读出            ByteArrayOutputStream os = new ByteArrayOutputStream();            try {                wb.write(os);            } catch (IOException e) {                           }            byte[] bytes= os.toByteArray();            try {                os.close();            } catch (IOException e) {                           }            return bytes;        } catch (Exception e) {                  }        return null;    }    private static final int MAX_ROWS=65530;    private static void createOnePage(HSSFWorkbook wb, List<Log> list, int start, int index) {        HSSFSheet sheet = wb.createSheet("sheet" + index);        // 样式对象        HSSFCellStyle cs0 = wb.createCellStyle();        cs0.setAlignment(HSSFCellStyle.ALIGN_CENTER);//        cs0.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);        cs0.setBorderBottom(HSSFCellStyle.BORDER_THIN);//        cs0.setBorderLeft(HSSFCellStyle.BORDER_THIN);//        cs0.setBorderRight(HSSFCellStyle.BORDER_THIN);//        cs0.setBorderTop(HSSFCellStyle.BORDER_THIN);//        cs0.setWrapText(true);        // 创建字体        HSSFFont ff0 = wb.createFont();        ff0.setFontHeightInPoints((short) 14);// 字体大小        ff0.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);   //字体加粗        cs0.setFont(ff0);//放入样式中        HSSFRow row0 = sheet.createRow(0);        row0.setHeight((short) 500);        HSSFCell cell0 = row0.createCell(0);        cell0.setCellValue("导出日志报表");        cell0.setCellStyle(cs0);        sheet.addMergedRegion(new Region(0, (short) 0, 0, (short) 2));//指定合并区域        // 样式对象        HSSFCellStyle cs = wb.createCellStyle();        cs.setAlignment(HSSFCellStyle.ALIGN_CENTER);//        cs.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);        cs.setBorderBottom(HSSFCellStyle.BORDER_THIN);//        cs.setBorderLeft(HSSFCellStyle.BORDER_THIN);//        cs.setBorderRight(HSSFCellStyle.BORDER_THIN);//        cs.setBorderTop(HSSFCellStyle.BORDER_THIN);//        cs.setWrapText(true);        // 创建字体        HSSFFont ff = wb.createFont();        ff.setFontHeightInPoints((short) 10);// 字体大小        ff.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);   //字体加粗        cs.setFont(ff);//放入样式中        // 样式对象        HSSFCellStyle cs2 = wb.createCellStyle();        cs2.setAlignment(HSSFCellStyle.ALIGN_CENTER);//        cs2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);        cs2.setBorderBottom(HSSFCellStyle.BORDER_THIN);//        cs2.setBorderLeft(HSSFCellStyle.BORDER_THIN);//        cs2.setBorderRight(HSSFCellStyle.BORDER_THIN);//        cs2.setBorderTop(HSSFCellStyle.BORDER_THIN);//        cs2.setWrapText(true);        // 创建字体        HSSFFont ff2 = wb.createFont();        ff2.setFontHeightInPoints((short) 10);// 字体大小        cs2.setFont(ff2);//放入样式中        HSSFRow row1 = sheet.createRow(1);        sheet.setColumnWidth(0, 32 * 200);        sheet.setColumnWidth(1, 32 * 150);        sheet.setColumnWidth(2, 32 * 900);        HSSFCell cell = row1.createCell(0);        cell.setCellValue("TIME");        cell.setCellStyle(cs);        cell = row1.createCell(1);        cell.setCellValue("IP");        cell.setCellStyle(cs);        cell = row1.createCell(2);        cell.setCellValue("DATA");        cell.setCellStyle(cs);        DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");        int len = start + MAX_ROWS <= list.size() ? MAX_ROWS : list.size() - start;        for (int i = 0; i < len; i++) {            Log log = list.get(start++);            HSSFRow row = sheet.createRow(i+2);            cell = row.createCell(0);            cell.setCellValue(df.format(log.getTime()));            cell.setCellStyle(cs2);            cell = row.createCell(1);            cell.setCellValue(log.getIP());            cell.setCellStyle(cs2);            cell = row.createCell(2);            cell.setCellValue(T.toJsonString(log.getText()));            cell.setCellStyle(cs2);        }    }}