java POI 单元格格式设置居中

 设置颜色,设置前景色

style.setFillForegroundColor(HSSFColor.HSSFColorPredefined.GREY_25_PERCENT.getIndex());
style.setFillPattern(FillPatternType.SOLID_FOREGROUND);

设置居中对齐 

//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);

自适应宽度

//自动设置行高
int colLength = cell.getStringCellValue().getBytes().length*256;  //
sheet.setColumnWidth(col, colLength);

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  dataList = new ArrayList();
	
	HttpServletResponse  response;
	
	//构造方法，传入要导出的数据
	public ExportExcel(String title,String[] rowName,List  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