java POI操作Excel代码收藏 （包括标题垂直水平居中）

package com.hwt.glmf.common;import java.io.IOException;import java.io.OutputStream;import java.util.ArrayList;import java.util.List;import javax.servlet.http.HttpServletResponse;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.HSSFRichTextString;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.hssf.util.CellRangeAddress;import org.apache.poi.hssf.util.HSSFColor;/** * 导出Excel公共方法 * @version 1.0 *  * @author wangcp * */public class ExportExcel extends BaseAction {//显示的导出表的标题private String title;//导出表的列名private String[] rowName ;private List<Object[]>  dataList = new ArrayList<Object[]>();HttpServletResponse  response;//构造方法，传入要导出的数据public ExportExcel(String title,String[] rowName,List<Object[]>  dataList){this.dataList = dataList;this.rowName = rowName;this.title = title;}/* * 导出数据 * */public void export() throws Exception{try{HSSFWorkbook workbook = new HSSFWorkbook();// 创建工作簿对象HSSFSheet sheet = workbook.createSheet(title); // 创建工作表// 产生表格标题行        HSSFRow rowm = sheet.createRow(0);        HSSFCell cellTiltle = rowm.createCell(0);                //sheet样式定义【getColumnTopStyle()/getStyle()均为自定义方法 - 在下面  - 可扩展】        HSSFCellStyle columnTopStyle = this.getColumnTopStyle(workbook);//获取列头样式对象        HSSFCellStyle style = this.getStyle(workbook);//单元格样式对象                sheet.addMergedRegion(new CellRangeAddress(0, 1, 0, (rowName.length-1)));          cellTiltle.setCellStyle(columnTopStyle);        cellTiltle.setCellValue(title);    // 定义所需列数int columnNum = rowName.length;HSSFRow rowRowName = sheet.createRow(2);// 在索引2的位置创建行(最顶端的行开始的第二行)// 将列头设置到sheet的单元格中for(int n=0;n<columnNum;n++){HSSFCell  cellRowName = rowRowName.createCell(n);//创建列头对应个数的单元格cellRowName.setCellType(HSSFCell.CELL_TYPE_STRING);//设置列头单元格的数据类型    HSSFRichTextString text = new HSSFRichTextString(rowName[n]);    cellRowName.setCellValue(text);//设置列头单元格的值    cellRowName.setCellStyle(columnTopStyle);//设置列头单元格样式    }    //将查询出的数据设置到sheet对应的单元格中for(int i=0;i<dataList.size();i++){Object[] obj = dataList.get(i);//遍历每个对象HSSFRow row = sheet.createRow(i+3);//创建所需的行数for(int j=0; j<obj.length; j++){HSSFCell  cell = null;   //设置单元格的数据类型if(j == 0){cell = row.createCell(j,HSSFCell.CELL_TYPE_NUMERIC);cell.setCellValue(i+1);}else{cell = row.createCell(j,HSSFCell.CELL_TYPE_STRING);if(!"".equals(obj[j]) && obj[j] != null){cell.setCellValue(obj[j].toString());//设置单元格的值}}cell.setCellStyle(style);//设置单元格样式}}//让列宽随着导出的列长自动适应for (int colNum = 0; colNum < columnNum; colNum++) {            int columnWidth = sheet.getColumnWidth(colNum) / 256;            for (int rowNum = 0; rowNum < sheet.getLastRowNum(); rowNum++) {                HSSFRow currentRow;                //当前行未被使用过                if (sheet.getRow(rowNum) == null) {                    currentRow = sheet.createRow(rowNum);                } else {                    currentRow = sheet.getRow(rowNum);                }                if (currentRow.getCell(colNum) != null) {                    HSSFCell currentCell = currentRow.getCell(colNum);                    if (currentCell.getCellType() == HSSFCell.CELL_TYPE_STRING) {                        int length = currentCell.getStringCellValue().getBytes().length;                        if (columnWidth < length) {                            columnWidth = length;                        }                    }                }            }            if(colNum == 0){            sheet.setColumnWidth(colNum, (columnWidth-2) * 256);            }else{            sheet.setColumnWidth(colNum, (columnWidth+4) * 256);            }        }if(workbook !=null){try    {        String fileName = "Excel-" + String.valueOf(System.currentTimeMillis()).substring(4, 13) + ".xls";        String headStr = "attachment; filename=\"" + fileName + "\"";        response = getResponse();        response.setContentType("APPLICATION/OCTET-STREAM");        response.setHeader("Content-Disposition", headStr);        OutputStream out = response.getOutputStream();        workbook.write(out);    }    catch (IOException e)    {        e.printStackTrace();    }}}catch(Exception e){e.printStackTrace();}}/*  * 列头单元格样式 */      public HSSFCellStyle getColumnTopStyle(HSSFWorkbook workbook) {      // 设置字体      HSSFFont font = workbook.createFont();      //设置字体大小      font.setFontHeightInPoints((short)11);      //字体加粗      font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);      //设置字体名字       font.setFontName("Courier New");      //设置样式;       HSSFCellStyle style = workbook.createCellStyle();      //设置底边框;       style.setBorderBottom(HSSFCellStyle.BORDER_THIN);      //设置底边框颜色;        style.setBottomBorderColor(HSSFColor.BLACK.index);      //设置左边框;         style.setBorderLeft(HSSFCellStyle.BORDER_THIN);      //设置左边框颜色;       style.setLeftBorderColor(HSSFColor.BLACK.index);      //设置右边框;       style.setBorderRight(HSSFCellStyle.BORDER_THIN);      //设置右边框颜色;       style.setRightBorderColor(HSSFColor.BLACK.index);      //设置顶边框;       style.setBorderTop(HSSFCellStyle.BORDER_THIN);      //设置顶边框颜色;        style.setTopBorderColor(HSSFColor.BLACK.index);      //在样式用应用设置的字体;        style.setFont(font);      //设置自动换行;       style.setWrapText(false);      //设置水平对齐的样式为居中对齐;        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);      //设置垂直对齐的样式为居中对齐;       style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);            return style;        }    /*   * 列数据信息单元格样式 */    public HSSFCellStyle getStyle(HSSFWorkbook workbook) {    // 设置字体    HSSFFont font = workbook.createFont();    //设置字体大小    //font.setFontHeightInPoints((short)10);    //字体加粗    //font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);    //设置字体名字     font.setFontName("Courier New");    //设置样式;     HSSFCellStyle style = workbook.createCellStyle();    //设置底边框;     style.setBorderBottom(HSSFCellStyle.BORDER_THIN);    //设置底边框颜色;      style.setBottomBorderColor(HSSFColor.BLACK.index);    //设置左边框;       style.setBorderLeft(HSSFCellStyle.BORDER_THIN);    //设置左边框颜色;     style.setLeftBorderColor(HSSFColor.BLACK.index);    //设置右边框;     style.setBorderRight(HSSFCellStyle.BORDER_THIN);    //设置右边框颜色;     style.setRightBorderColor(HSSFColor.BLACK.index);    //设置顶边框;     style.setBorderTop(HSSFCellStyle.BORDER_THIN);    //设置顶边框颜色;      style.setTopBorderColor(HSSFColor.BLACK.index);    //在样式用应用设置的字体;      style.setFont(font);    //设置自动换行;     style.setWrapText(false);    //设置水平对齐的样式为居中对齐;      style.setAlignment(HSSFCellStyle.ALIGN_CENTER);    //设置垂直对齐的样式为居中对齐;     style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);       return style;    }}