jxl 实现根据sql语句导出excel文件

/**
	 * 导出Excel
	 * @param filePath			导出文件（模板）路径
	 * @param sql				导出的SQL语句
	 * @param startLine			起始行
	 * @param printTitle		是否打印标题
	 * @throws Exception
	 */
	public void doExport(String filePath , String sql , int startLine , boolean printTitle) throws Exception  {
		
		
		Class.forName("oracle.jdbc.driver.OracleDriver");
		Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@127.0.0.1:1521:yz", "scott", "tiger"); //获取数据库连接 
		WritableWorkbook book = null ;
		WritableSheet sheet = null ;
		 
		if(new File(filePath).exists()){
			Workbook wb = Workbook.getWorkbook(new File(filePath)); 
			book = Workbook.createWorkbook(new File(filePath), wb); 								// 添加一个工作表
			sheet = book.getSheet(0);	
		}else {
			book = Workbook.createWorkbook(new File(filePath));	 							 	 	 // 第一步
			sheet = book.createSheet("第一页", 0); 						 							 // 创建Sheet
		}
		
		
		PreparedStatement pstm = conn.prepareStatement(sql);							
		ResultSet rs = pstm.executeQuery();							//获取数据集
		ResultSetMetaData rsmd = rs.getMetaData();					//获取表头
		int colCnt = rsmd.getColumnCount();							//获取数据集的列数
		
		
		if(printTitle){
			
			/**
			 * 定义单元格样式
			 */
			WritableFont wf = new WritableFont(WritableFont.ARIAL, 15, WritableFont.BOLD, false, UnderlineStyle.NO_UNDERLINE,Colour.BLACK); // 定义格式 字体 下划线 斜体 粗体 颜色
			WritableCellFormat wcf = new WritableCellFormat(wf); // 单元格定义
			wcf.setBackground(jxl.format.Colour.BLACK); // 设置单元格的背景颜色
			wcf.setAlignment(jxl.format.Alignment.CENTRE); // 设置对齐方式
			sheet.setRowView(startLine, 1000); // 设置行的高度
			
			//打印标题头
			for(int k = 1; k < colCnt + 1; k++){
				String title = rsmd.getColumnName(k);
				Label labelTitle = new Label( k-1 , startLine , title , wcf);
				sheet.setColumnView(k-1 , 30); // 设置列的宽度
				sheet.addCell(labelTitle);
			}
			startLine++ ;
		}
		
		
		//打印sql语句查出来的数据
		while (rs.next()) {
			for (int j = 1; j < colCnt+1; j++) {
				String colName = rsmd.getColumnName(j);
				String colValue = rs.getString(colName);
				Label label = new Label(j-1, startLine, colValue);
				sheet.addCell(label);
			}
			startLine++;
		}
		
		  
		book.write();
		book.close();
		pstm.close();
		conn.close();
	}