我有一个结果集，我必须将结果集中的所有可用数据写入一个文本文件，并将其填充给用户以供下载。
我已经完成了以下代码以使用 poi 导出到 excel，与文本文件的操作方式相同。
if(exportTo.equals("excel"))
{
response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-disposition", "attachment; filename=\"" + reportName + ".xls\"");
try {
HSSFWorkbook hwb = new HSSFWorkbook();
HSSFSheet sheet = hwb.createSheet(reportName);
HSSFRow row = null;
HSSFHeader header = sheet.getHeader();
header.setCenter("POC");
header.setLeft("POC");
header.setRight(HSSFHeader.font("Stencil-Normal", "Italic") +
HSSFHeader.fontSize((short) 16) + reportName);
//to add water mark
/*HSSFPatriarch dp = sheet.createDrawingPatriarch();
HSSFClientAnchor anchor = new HSSFClientAnchor
(0, 0, 1023, 255, (short) 2, 4, (short) 13, 26);
HSSFTextbox txtbox = dp.createTextbox(anchor);
HSSFRichTextString rtxt = new HSSFRichTextString("POC");
HSSFFont draftFont = hwb.createFont();
draftFont.setColor((short) 27);
draftFont.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
draftFont.setFontHeightInPoints((short) 192);
draftFont.setFontName("Verdana");
rtxt.applyFont(draftFont);
txtbox.setString(rtxt);
txtbox.setLineStyle(HSSFShape.LINESTYLE_NONE);
txtbox.setNoFill(true);*/
HSSFCellStyle style = hwb.createCellStyle();
style.setBorderTop((short) 6); // double lines border
style.setBorderBottom((short) 1); // single line border
style.setFillBackgroundColor(HSSFColor.GREY_25_PERCENT.index);
HSSFFont font = hwb.createFont();
font.setBoldweight((short) 700);
// Create Styles for sheet.
HSSFCellStyle headerStyle = hwb.createCellStyle();
headerStyle.setFillForegroundColor(HSSFColor.GREY_25_PERCENT.index);
headerStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
headerStyle.setFont(font);
headerStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
headerStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
headerStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
headerStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
headerStyle.setAlignment((short) 2);
// create Title for the sheet
HSSFCellStyle titleStyle = hwb.createCellStyle();
HSSFFont titleFont = hwb.createFont();
titleFont.setFontName(HSSFFont.FONT_ARIAL);
titleFont.setFontHeightInPoints((short) 15);
titleFont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
titleFont.setColor(HSSFColor.BLUE.index);
titleStyle.setFont(titleFont);
titleStyle.setAlignment((short)2);
row = sheet.createRow((short)1);
HSSFCell secondCell = row.createCell((short) 0);
secondCell.setCellValue(new HSSFRichTextString(reportName).toString());
secondCell.setCellStyle(titleStyle);
sheet.addMergedRegion(new Region(1, (short)0, 1, (short)headerCount));
int sno=0;
HSSFRow rowhead = sheet.createRow((short)4);
for (Iterator it = headerMap.keySet().iterator(); it.hasNext();) {
String headerName = (String) headerMap.get(it.next());
HSSFCell headerCell = rowhead.createCell((short)sno);
headerCell.setCellStyle(headerStyle);
headerCell.setCellValue(headerName);
sno++;
}
HSSFCellStyle rowStyle=hwb.createCellStyle();
rowStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
rowStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
rowStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
rowStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
rowStyle.setAlignment((short) 2);
row = custDAO.creadExcelTable(query, sheet, row,rowStyle);
hwb.write(response.getOutputStream());
response.flushBuffer();
} catch (Exception ex) {
ex.printStackTrace();
}
}
public HSSFRow creadExcelTable(String query,HSSFSheet sheet,HSSFRow row,HSSFCellStyle rowStyle ){
int numberOfColumns=0,sno=0,index=5,iterator=1;
Connection connection = getConnection();
if (connection != null) {
try {
PreparedStatement reportTablePS = connection.prepareStatement(query);
ResultSet reportTable_rst = reportTablePS.executeQuery();
ResultSetMetaData reportTable_rsmd = reportTable_rst.getMetaData();
numberOfColumns = reportTable_rsmd.getColumnCount();
int i =0;
while (reportTable_rst.next()) {
row = sheet.createRow((short)index);
sheet.setColumnWidth((short)index, (short)100);
/* if(i == 0){
i = 1;
rowStyle.setFillForegroundColor(HSSFColor.BLUE_GREY.index);
rowStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
System.out.println("BLUE_GREY");
}
else {
i = 0;
System.out.println("LEMON");
rowStyle.setFillForegroundColor(HSSFColor.LEMON_CHIFFON.index);
rowStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
}*/
HSSFCell serialCell = row.createCell((short)sno);
serialCell.setCellStyle(rowStyle);
serialCell.setCellValue(iterator);
for (int columnIterator = 1; columnIterator <= numberOfColumns; columnIterator++) {
String column = reportTable_rst.getString(columnIterator);
sheet.setColumnWidth((short)columnIterator, (short)3000);
HSSFCell rowCell = row.createCell((short)columnIterator);
rowCell.setCellStyle(rowStyle);
rowCell.setCellValue(column);
}
index++;
iterator++;
}
} catch (Exception ex) {
ex.printStackTrace();
}finally {
try {
closeConnection(connection, null, null);
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
return row;
}
现在我已经完成了这个，真的不知道该怎么做
if(exportTo.equals("text")){
response.setContentType("text/plain");
response.setHeader("Content-disposition", "attachment; filename=\"" + reportName + ".txt\"");
try {
} catch (Exception e) {
// TODO: handle exception
}
}
这个用于在指定位置创建文件
Writer writer = null;
try {
String text = "This is a text file";
File file = new File("write.txt");
writer = new BufferedWriter(new FileWriter(file));
writer.write(text);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (writer != null) {
writer.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
但我想用对话框导出文件，请帮助我如何去做。
问候