我有这个 servlet 来处理上传的文件并将它们存储在服务器上。
public class ImageService extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 1L;
private static final long MAX_FILE_SIZE = 1024 * 1024 * 1024; // 1GB
@Override
protected void doPost(final HttpServletRequest request,
final HttpServletResponse response) {
slog("SERVLET STARTED");
List<String> files = new ArrayList<String>();
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (isMultipart) {
slog("REQUEST IS MULTIPART");
response.setStatus(HttpServletResponse.SC_OK);
response.setContentType("text/html");
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
upload.setFileSizeMax(MAX_FILE_SIZE);
try {
List<FileItem> items = upload.parseRequest(request);
Iterator<FileItem> iterator = items.iterator();
while (iterator.hasNext()) {
FileItem item = iterator.next();
if (!item.isFormField()) {
String fileName = item.getName();
slog("TROVATO FILE " + item.getName());
String root = getServletContext().getRealPath("/");
File path = new File(root + "/fileuploads");
slog("SALVO FILE IN " + path.getAbsolutePath());
if (!path.exists()) {
path.mkdirs();
}
File uploadedFile = creaFileNonAmbiguo(path, fileName);
slog("NOME ASSEGNATO AL FILE " + uploadedFile.getName());
item.write(uploadedFile);
response.getWriter()
.write(uploadedFile.getName() + ";");
files.add(uploadedFile.getName());
}
}
response.getWriter().flush();
slog("RISPOSTA INVIATA");
} catch (Exception e) {
e.printStackTrace();
}
} else {
slog("LA RICHIESTA NON E' MULTIPART");
response.setStatus(HttpServletResponse.SC_NO_CONTENT);
}
slog("SERVLET TERMINATA");
}
@Override
protected void doGet(final HttpServletRequest request,
final HttpServletResponse response) {
response.setContentType("image/jpeg");
String root = getServletContext().getRealPath("/").concat(
"fileuploads/");
String path = root.concat(request.getParameter("src"));
File file = new File(path);
response.setContentLength((int) file.length());
FileInputStream in;
try {
in = new FileInputStream(file);
OutputStream out = response.getOutputStream();
byte[] buf = new byte[1024];
int len = 0;
while ((len = in.read(buf)) >= 0) {
out.write(buf, 0, len);
}
in.close();
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private File creaFileNonAmbiguo(File path, String fileName) {
File res = new File(path + "/" + fileName);
if (!res.exists())
return res;
else {
return creaFileNonAmbiguo(path, "c".concat(fileName));
}
}
private void slog(String s) {
System.out.println("UPLOAD SERVLET: " + s);
}
}
如您所见，servlet 具有 doPost 和 doGet。在我的这部分代码中正确调用了 doGet()：
[...]
String path = GWT.getModuleBaseURL() + "imageUpload?src=";
for (String foto : result) {
String url = path.concat(foto);
[...]
SERVLET STARTED但是 doPost 方法从未被调用，正如我从 Chrome 调试器和从未记录的事实中看到的那样。
这是我从客户端调用 doPost() 方法的方式：
inserisciSegnalazioneBtn.addClickHandler(new ClickHandler() {
@Override
public void onClick(ClickEvent event) {
if (!catLst.isEnabled()
|| catLst.getItemText(catLst.getSelectedIndex())
.equals("")
|| catLst.getItemText(catLst.getSelectedIndex())
.equals("")
|| descrizioneBox.getText().equals("")
|| gsb.getText().equals("")) {
Window.alert("ATTENZIONE: devi riempire tutti i campi");
return;
}
segnalazione.setCategoria(new Categoria(catLst.getItemText(catLst
.getSelectedIndex())));
segnalazione.setDescrizione(descrizioneBox.getText());
segnalazione.setIndirizzo(gsb.getText());
segnalazione.setUtente(LoginPanel.username);
Segnalazioni_Degrado.dataLayerService.inserisciSegnalazione(
segnalazione, new AsyncCallback<Boolean>() {
@Override
public void onFailure(Throwable caught) {
caught.printStackTrace();
}
@Override
public void onSuccess(Boolean result) {
if (result) {
geocode(segnalazione);
uploadFrm.submit();
Window.alert("Inserimento avvenuto con successo");
MenuPanel.refreshBtn.click();
} else
Window.alert("L'inserimento ha avuto esito negativo");
thisPnl.hide();
}
});
}
});
uploadFrm.setAction(GWT.getModuleBaseURL() + "imageUpload");
uploadFrm.setEncoding(FormPanel.ENCODING_MULTIPART);
uploadFrm.setMethod(FormPanel.METHOD_POST);
uploadFrm
.addSubmitCompleteHandler(new FormPanel.SubmitCompleteHandler() {
@Override
public void onSubmitComplete(SubmitCompleteEvent event) {
Window.alert("SUBMIT COMPLETATO");
String res = event.getResults();
if (res != null && !res.equals("")) {
Window.alert("IL SERVER RISPONDE " + res.toString());
String[] uploadedFiles = res.split(";");
aggiornaFotoDB(uploadedFiles, segnalazione);
}
}
});
奇怪的是它在 DevMode 上正常工作，但是当我将我的 webapp 部署到 Tomcat 时它不起作用。我的代码有什么问题？