JAVA将执行sql结果导入excel

public String queryResultToExcel(String sql,String filename,OutputStream os) {
Connection conn = null;
Statement sm = null;
ResultSet rs = null;
try {
conn = getConnection();
sm = conn.createStatement();
rs = sm.executeQuery(sql);
ResultSetMetaData rsmd = rs.getMetaData();
WritableWorkbook wwb = Workbook.createWorkbook(os); // 建立excel文件
WritableSheet sheet = wwb.createSheet(filename, 10); // 创建一个工作表
// 设置单元格的文字格式
WritableFont wf = new WritableFont(WritableFont.ARIAL, 10, WritableFont.BOLD, false, UnderlineStyle.NO_UNDERLINE, Colour.BLACK);
WritableCellFormat wcf = new WritableCellFormat(wf);
wcf.setVerticalAlignment(VerticalAlignment.CENTRE);
wcf.setAlignment(Alignment.LEFT);

// 格式化数据--NUMBER类型
NumberFormat numberFormat = new NumberFormat(###0.0#######);
WritableCellFormat cellFormatNumber = new WritableCellFormat(numberFormat);
cellFormatNumber.setVerticalAlignment(VerticalAlignment.CENTRE);
cellFormatNumber.setAlignment(Alignment.RIGHT);

NumberFormat numberFormat2 = new NumberFormat(###0);
WritableCellFormat cellFormatNumber2 = new WritableCellFormat(numberFormat2);
cellFormatNumber2.setVerticalAlignment(VerticalAlignment.CENTRE);
cellFormatNumber2.setAlignment(Alignment.RIGHT);

// 格式化数据--DATE类型
DateFormat dateFormat=new DateFormat(yyyy-MM-dd);
WritableCellFormat cellFormatDate = new WritableCellFormat(dateFormat);
cellFormatDate.setVerticalAlignment(VerticalAlignment.CENTRE);
cellFormatDate.setAlignment(Alignment.CENTRE);
// 格式化数据--文本
WritableCellFormat  cellTextFormat = new WritableCellFormat(NumberFormats.TEXT);
cellTextFormat.setAlignment(Alignment.CENTRE);
cellTextFormat.setVerticalAlignment(VerticalAlignment.CENTRE);

// 表体数据
boolean flag = true;
int r = 1;
int c = 0;
int columns = rsmd.getColumnCount();
//缓存最大标题宽度
Vector<integer> colWidth = new Vector<integer>();
for(int i = 1; i <= columns; i++){
colWidth.add(0);
}

while (rs.next()) {
for (int i = 1; i <= columns; i++) {
//添加表头数据
if(flag){
String key = rsmd.getColumnName(i).toLowerCase();
sheet.setColumnView(c, key.getBytes(GBK).length + 4);
sheet.addCell(new Label(c, 0, key,wcf));
colWidth.set(i-1, key.getBytes(GBK).length); //缓存每列第一行数据的宽度
}

//设置列宽--如果下一列的数据比前一列宽，则保存最大宽度
if(rs.getString(i) != null){
if(colWidth.get(i-1)<rs.getstring(i).length()){ auto-generated="" block="" c="0;" catch="" else="" filenotfoundexception="" finally="" flag="false;" if="" ioexception="" new="" pre="" return="" sqlexception="" todo="" try="" writeexception=""><p> </p></rs.getstring(i).length()){></integer></integer>