我正在开发一个应用程序，我想通过调用服务从应用程序创建一个'MS-EXCEL'文件，我想将该文件作为对客户端机器的响应返回，并带有保存文件的对话框。
目前我正在编写程序中的路径。我不能使用swing我想在GWT中实现它。
if (name.equalsIgnoreCase("DigitalInputReport")) {
response.setHeader(
"Content-disposition",
"attachment; filename=\"DIR_"
+ TimeZoneUtil.getPdfDate(fromDate) + "_"
+ TimeZoneUtil.getPdfDate(toDate) + ".csv\"");
List<ReportData> datas = new ArrayList<ReportData>();
// Calling Service
datas = fleetTrackingServiceImpl.getDIN2SummaryReport(vehicle,
fromDate, toDate);
FileWriter writer = new FileWriter("C:\\Windows\\Temp\\DIR_"
+ TimeZoneUtil.getPdfDate(fromDate) + "_"
+ TimeZoneUtil.getPdfDate(toDate) + ".csv");
try {
hashMapRunDur = datas.get(datas.size() - 1).getRunHashMap();
hashMapStopDur = datas.get(datas.size() - 1)
.getStopHashMap();
int runDur = 0, stopDur = 0;
writer.append("From Hour");
writer.append(',');
writer.append("To Hour");
writer.append(',');
writer.append("Minutes ON");
writer.append(',');
writer.append("Minutes OFF");
writer.append(',');
writer.append('\n');
writer.append("Date");
writer.append(',');
String dtChk = null, dtChkPrev = null;
for (int i = 0; i < datas.size(); i++) {
if (i == 0) {
dtChk = datas.get(i).getToDate();
writer.append(datas.get(i).getToDate());
writer.append(',');
writer.append('\n');
writer.append(datas.get(i).getRunTime());
writer.append(',');
writer.append(datas.get(i).getStopTime());
writer.append(',');
writer.append(datas.get(i).getRunDur());
writer.append(',');
writer.append(datas.get(i).getStopDur());
writer.append('\n');
} else {
dtChkPrev = dtChk;
dtChk = datas.get(i).getToDate();
if (dtChkPrev.equals(dtChk)) {
writer.append(datas.get(i).getRunTime());
writer.append(',');
writer.append(datas.get(i).getStopTime());
writer.append(',');
writer.append(datas.get(i).getRunDur());
writer.append(',');
writer.append(datas.get(i).getStopDur());
writer.append('\n');
} else {
for (Map.Entry<String, String> e : hashMapRunDur
.entrySet()) {
runDur = (Integer.valueOf(e.getValue()));
stopDur = (Integer.valueOf(hashMapStopDur
.get(e.getKey())));
break;
}
// To delete first entry
Iterator<Map.Entry<String, String>> iterRun = hashMapRunDur
.entrySet().iterator();
while (iterRun.hasNext()) {
Map.Entry<String, String> entry = iterRun
.next();
if (datas.get(i - 1).getToDate()
.equalsIgnoreCase(entry.getKey())) {
iterRun.remove();
}
}
Iterator<Map.Entry<String, String>> iterStop = hashMapStopDur
.entrySet().iterator();
while (iterStop.hasNext()) {
Map.Entry<String, String> entry = iterStop
.next();
if (datas.get(i - 1).getToDate()
.equalsIgnoreCase(entry.getKey())) {
iterStop.remove();
}
}
writer.append(' ');
writer.append(',');
writer.append("Total ON/OFF");
writer.append(',');
writer.append(formatIntoHHMMSSWithOutDay(runDur));
writer.append(',');
writer.append(formatIntoHHMMSSWithOutDay(stopDur));
writer.append(',');
writer.append('\n');
dtChk = datas.get(i).getToDate();
writer.append("Date");
writer.append(',');
writer.append(datas.get(i).getToDate());
writer.append(',');
writer.append('\n');
writer.append(datas.get(i).getRunTime());
writer.append(',');
writer.append(datas.get(i).getStopTime());
writer.append(',');
writer.append(datas.get(i).getRunDur());
writer.append(',');
writer.append(datas.get(i).getStopDur());
writer.append('\n');
}
if (i == datas.size() - 1) {
for (Map.Entry<String, String> e : hashMapRunDur
.entrySet()) {
runDur = (Integer.valueOf(e.getValue()));
stopDur = (Integer.valueOf(hashMapStopDur
.get(e.getKey())));
break;
}
writer.append(' ');
writer.append(',');
writer.append("Total ON/OFF");
writer.append(',');
writer.append(formatIntoHHMMSSWithOutDay(runDur));
writer.append(',');
writer.append(formatIntoHHMMSSWithOutDay(stopDur));
writer.append(',');
writer.append('\n');
}
}
}
} catch (IOException e) {
e.printStackTrace();
} finally {
writer.flush();
writer.close();
}
}
这是Servlet编码。当我调用它时，我在这里得到输出（c：// windows / temp / DIR _...），其中包含完整内容但不在我在客户端下载的文件中（我只获得'DigitalInputReport'）。请简要解释一下......
csvBtn.addSelectionListener(new SelectionListener<ButtonEvent>() {
@Override
public void componentSelected(ButtonEvent ce) {
String gwt = GWT.getHostPageBaseURL();
Window.open(
gwt
+ "generateCSVServlet?name=DigitalInputReport&fromDate="
+ fromDate + "&toDate=" + toDate + "&compName="
+ LoginDashboardModule.companyId
+ "&brnchName=" + LoginDashboardModule.branchId
+ "&userName=" + LoginDashboardModule.userName
+ "&selectedVehicle=" + selectedVehicle, null, null);
}
});
这是客户端代码
答案 0 :(得分：3)
File temp = new File("C:\\Windows\\Temp\\DIR_"
+ TimeZoneUtil.getPdfDate(fromDate) + "_"
+ TimeZoneUtil.getPdfDate(toDate) + ".csv");
try (BufferedReader br = new BufferedReader(new FileReader(temp)))
{
String isCurrentLine;
while ((isCurrentLine = br.readLine()) != null) {
response.getOutputStream().write("\n".getBytes());
byte[] b = isCurrentLine.getBytes();
response.getOutputStream().write(b);
}
} catch (IOException e) {
e.printStackTrace();
}
使用此代码，我可以直接从服务器端向客户端返回文件内容，并按照自己的意愿将文件保存在客户端计算机上。
答案 1 :(得分：1)
使用FileUpload获取路径。
A widget that wraps the HTML <input type='file'> element.
在changeEvent中你可以得到文件名/路径：
FileUpload file = (FileUpload) event.getSource();
String filename = file.getFilename();