【poi】sqlserver 数据写入到 excel

使用 c3p0获取 DataSource

public class DataSourceUtils {
	private static DataSource ds;
	static{
		//默认的读取c3p0-config.xml中默认配置
		ds = new ComboPooledDataSource();
	}
	public static DataSource getDatasSource(){
		return ds;
	}
	public static Connection getConn(){
		Connection con = null;
		try{
			con = ds.getConnection();//每一次从ds中获取一个新的连接
		}catch(Exception e){
			e.printStackTrace();
		}
		return con;
	}
}

使用 poi 将数据写入到excel中

public void createXls() throws Exception{
		//声明一个工作薄
		HSSFWorkbook wb = new HSSFWorkbook();
	   //声明表
		HSSFSheet sheet = wb.createSheet("第一个表");
		//声明行
		HSSFRow row = sheet.createRow(7);
		//声明列
		HSSFCell cel = row.createCell(3);
		//写入数据
		cel.setCellValue("你也好");
		
		FileOutputStream fileOut = new FileOutputStream("d:/a/b.xls");
	    wb.write(fileOut);
	    
	    fileOut.close();
	}
	
	@Test
	public void export() throws Exception{
		//声明需要导出的数据库
		String dbName = "contact";
		//声明book
		HSSFWorkbook book = new HSSFWorkbook();
		//获取Connection,获取db的元数据
		Connection con = DataSourceUtils.getConn();
		//声明statemen
		Statement st = con.createStatement();
		//st.execute("use "+dbName);
		DatabaseMetaData dmd = con.getMetaData();
		//获取数据库有多少表
		ResultSet rs = dmd.getTables(null,null,null,new String[]{"TABLE"});
		//获取所有表名　－　就是一个sheet
		List<String> tables = new ArrayList<String>();
		while(rs.next()){
			String tableName = rs.getString("TABLE_NAME");
			System.out.println("**********" + tableName);
			tables.add(tableName);
		}
		for(String tableName:tables){
			HSSFSheet sheet = book.createSheet(tableName);
			//声明sql
			String sql = "SELECT * FROM "+tableName;
			//查询数据
			rs = st.executeQuery(sql);
			//根据查询的结果，分析结果集的元数据
			ResultSetMetaData rsmd = rs.getMetaData();
			//获取这个查询有多少行
			int cols = rsmd.getColumnCount();
			//获取所有列名
			//创建第一行
			HSSFRow row = sheet.createRow(0);
			for(int i=0;i<cols;i++){
				String colName = rsmd.getColumnName(i+1);
				//创建一个新的列
				HSSFCell cell = row.createCell(i);
				//写入列名
				cell.setCellValue(colName);
			}
			//遍历数据
			int index = 1;
			while(rs.next()){
				row = sheet.createRow(index++);
				//声明列
				for(int i=0;i<cols;i++){
					String val = rs.getString(i+1);
					//声明列
					HSSFCell cel = row.createCell(i);
					//放数据
					cel.setCellValue(val);
				}
			}
		}
		con.close();
		book.write(new FileOutputStream("d:/a/"+dbName+".xls"));
	}