Hallo 
Zunächst: ich bin absoluter Anfänger, aber muss für ein Webprojekt eine Dynamische Webanwendung mit best. Vorraussetzungen programmieren.
Seit gestern Abend sitze ich allerdings vor folgendem Problem und andere Foren helfen mir leider nicht weiter. Ich hoffe wirklich ihr könnt mir helfen und meinen Fehler finden!!
Ich habe versucht Daten über ein Servlet in eine Datenbank zu laden. Ich bekomme allerdings immer eine Fehlermedung, sobald ich das Projekt auf dem Tomcat 8.0 laufen lasse.
Fehlermeldung:
HTTP Status 404 - /ServletExamples/uploadToDB
type Status report
message /ServletExamples/uploadToDB
description The requested resource is not available.
Apache Tomcat/8.0.44
Da ich mich nicht auskenne, habe ich mehrere Examples zu dem Thema ausprobiert, unter anderem dieses Beispiel. Kein einziges Funktioniert bei mir. Sobald ich mir Response bzw. get und post Methoden arbeite funktioniert nichts mehr.
ich habe folgende Ordnerstruktur:
Java Resources
'-src
'-org.o7planning.servletexamples
'-uploadToDBResultsServlet.java
'-uploadToDBServlet.java
WebContent
'-META-INF
'-WEB-INF
'-jsps
'-uploadToDB.jsp
'-uploadToDBResults.jsp
'-lib
Ich habe folgenden Code verwendet:
upload.ToDBResultsServlet.java
package org.o7planning.servletexamples;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/uploadToDBResults")
public class uploadToDBResultsServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public uploadToDBResultsServlet() {
super();
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
RequestDispatcher dispatcher
= request.getServletContext().getRequestDispatcher("/WEB-INF/jsps/uploadToDBResults.jsp");
dispatcher.forward(request, response);
}
}
uploadToDBServlet.java
package org.o7planning.servletexamples;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
import org.o7planning.tutorial.jdbc.ConnectionUtils;
@WebServlet("/uploadToDB")
@MultipartConfig(fileSizeThreshold = 1024 * 1024 * 2, // 2MB
maxFileSize = 1024 * 1024 * 10, // 10MB
maxRequestSize = 1024 * 1024 * 50) // 50MB
public class uploadToDBServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
RequestDispatcher dispatcher = request.getServletContext().getRequestDispatcher("/WEB-INF/jsps/uploadToDB.jsp");
dispatcher.forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Connection conn = null;
try {
// Connection to Database
// (See more in JDBC Tutorial).
conn = ConnectionUtils.getMyConnection();
conn.setAutoCommit(false);
String description = request.getParameter("description");
// Part list (multi files).
for (Part part : request.getParts()) {
String fileName = extractFileName(part);
if (fileName != null && fileName.length() > 0) {
// File data
InputStream is = part.getInputStream();
// Write to file
this.writeToDB(conn, fileName, is, description);
}
}
conn.commit();
// Upload successfully!.
response.sendRedirect(request.getContextPath() + "/uploadToDBResults");
} catch (Exception e) {
e.printStackTrace();
request.setAttribute("errorMessage", "Error: " + e.getMessage());
RequestDispatcher dispatcher = getServletContext().getRequestDispatcher("/WEB-INF/jsps/uploadToDB.jsp");
dispatcher.forward(request, response);
} finally {
this.closeQuietly(conn);
}
}
private String extractFileName(Part part) {
// form-data; name="file"; filename="C:\file1.zip"
// form-data; name="file"; filename="C:\Note\file2.zip"
String contentDisp = part.getHeader("content-disposition");
String[] items = contentDisp.split(";");
for (String s : items) {
if (s.trim().startsWith("filename")) {
// C:\file1.zip
// C:\Note\file2.zip
String clientFileName = s.substring(s.indexOf("=") + 2, s.length() - 1);
clientFileName = clientFileName.replace("\\", "/");
int i = clientFileName.lastIndexOf('/');
// file1.zip
// file2.zip
return clientFileName.substring(i + 1);
}
}
return null;
}
private Long getMaxAttachmentId(Connection conn) throws SQLException {
String sql = "Select max(a.id) from Attachment a";
PreparedStatement pstm = conn.prepareStatement(sql);
ResultSet rs = pstm.executeQuery();
if (rs.next()) {
long max = rs.getLong(1);
return max;
}
return 0L;
}
private void writeToDB(Connection conn, String fileName, InputStream is, String description) throws SQLException {
String sql = "Insert into Attachment(Id,File_Name,File_Data,Description) " //
+ " values (?,?,?,?) ";
PreparedStatement pstm = conn.prepareStatement(sql);
Long id = this.getMaxAttachmentId(conn) + 1;
pstm.setLong(1, id);
pstm.setString(2, fileName);
pstm.setBlob(3, is);
pstm.setString(4, description);
pstm.executeUpdate();
}
private void closeQuietly(Connection conn) {
try {
if (conn != null) {
conn.close();
}
} catch (Exception e) {
}
}
}
uploadToDB.jsp
<!DOCTYPE >
<html>
<head>
<title>Upload files</title>
</head>
<body>
<div style="padding:5px; color:red;font-style:italic;">
${errorMessage}
</div>
<h2>Upload Files</h2>
<form method="post" action="${pageContext.request.contextPath}/uploadToDB"
enctype="multipart/form-data">
Select file to upload:
<br />
<input type="file" name="file" />
<br />
<input type="file" name="file" />
<br />
Description:
<br />
<input type="text" name="description" size="100" />
<br />
<br />
<input type="submit" value="Upload" />
</form>
</body>
</html>
uploadToDBR.jsp
<!DOCTYPE >
<html>
<head>
<title>Upload files</title>
</head>
<body>
<h3>Upload has been done successfully!</h3>
<a href="${pageContext.request.contextPath}/uploadToDB">Continue Upload</a>
</body>
</html>
Ich hoffe wirklich ich wisst weiter. Danke schonmal im Voraus!
Zunächst: ich bin absoluter Anfänger, aber muss für ein Webprojekt eine Dynamische Webanwendung mit best. Vorraussetzungen programmieren.
Seit gestern Abend sitze ich allerdings vor folgendem Problem und andere Foren helfen mir leider nicht weiter. Ich hoffe wirklich ihr könnt mir helfen und meinen Fehler finden!!
Ich habe versucht Daten über ein Servlet in eine Datenbank zu laden. Ich bekomme allerdings immer eine Fehlermedung, sobald ich das Projekt auf dem Tomcat 8.0 laufen lasse.
Fehlermeldung:
HTTP Status 404 - /ServletExamples/uploadToDB
type Status report
message /ServletExamples/uploadToDB
description The requested resource is not available.
Apache Tomcat/8.0.44
Da ich mich nicht auskenne, habe ich mehrere Examples zu dem Thema ausprobiert, unter anderem dieses Beispiel. Kein einziges Funktioniert bei mir. Sobald ich mir Response bzw. get und post Methoden arbeite funktioniert nichts mehr.
ich habe folgende Ordnerstruktur:
Java Resources
'-src
'-org.o7planning.servletexamples
'-uploadToDBResultsServlet.java
'-uploadToDBServlet.java
WebContent
'-META-INF
'-WEB-INF
'-jsps
'-uploadToDB.jsp
'-uploadToDBResults.jsp
'-lib
Ich habe folgenden Code verwendet:
upload.ToDBResultsServlet.java
package org.o7planning.servletexamples;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/uploadToDBResults")
public class uploadToDBResultsServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public uploadToDBResultsServlet() {
super();
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
RequestDispatcher dispatcher
= request.getServletContext().getRequestDispatcher("/WEB-INF/jsps/uploadToDBResults.jsp");
dispatcher.forward(request, response);
}
}
uploadToDBServlet.java
package org.o7planning.servletexamples;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
import org.o7planning.tutorial.jdbc.ConnectionUtils;
@WebServlet("/uploadToDB")
@MultipartConfig(fileSizeThreshold = 1024 * 1024 * 2, // 2MB
maxFileSize = 1024 * 1024 * 10, // 10MB
maxRequestSize = 1024 * 1024 * 50) // 50MB
public class uploadToDBServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
RequestDispatcher dispatcher = request.getServletContext().getRequestDispatcher("/WEB-INF/jsps/uploadToDB.jsp");
dispatcher.forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Connection conn = null;
try {
// Connection to Database
// (See more in JDBC Tutorial).
conn = ConnectionUtils.getMyConnection();
conn.setAutoCommit(false);
String description = request.getParameter("description");
// Part list (multi files).
for (Part part : request.getParts()) {
String fileName = extractFileName(part);
if (fileName != null && fileName.length() > 0) {
// File data
InputStream is = part.getInputStream();
// Write to file
this.writeToDB(conn, fileName, is, description);
}
}
conn.commit();
// Upload successfully!.
response.sendRedirect(request.getContextPath() + "/uploadToDBResults");
} catch (Exception e) {
e.printStackTrace();
request.setAttribute("errorMessage", "Error: " + e.getMessage());
RequestDispatcher dispatcher = getServletContext().getRequestDispatcher("/WEB-INF/jsps/uploadToDB.jsp");
dispatcher.forward(request, response);
} finally {
this.closeQuietly(conn);
}
}
private String extractFileName(Part part) {
// form-data; name="file"; filename="C:\file1.zip"
// form-data; name="file"; filename="C:\Note\file2.zip"
String contentDisp = part.getHeader("content-disposition");
String[] items = contentDisp.split(";");
for (String s : items) {
if (s.trim().startsWith("filename")) {
// C:\file1.zip
// C:\Note\file2.zip
String clientFileName = s.substring(s.indexOf("=") + 2, s.length() - 1);
clientFileName = clientFileName.replace("\\", "/");
int i = clientFileName.lastIndexOf('/');
// file1.zip
// file2.zip
return clientFileName.substring(i + 1);
}
}
return null;
}
private Long getMaxAttachmentId(Connection conn) throws SQLException {
String sql = "Select max(a.id) from Attachment a";
PreparedStatement pstm = conn.prepareStatement(sql);
ResultSet rs = pstm.executeQuery();
if (rs.next()) {
long max = rs.getLong(1);
return max;
}
return 0L;
}
private void writeToDB(Connection conn, String fileName, InputStream is, String description) throws SQLException {
String sql = "Insert into Attachment(Id,File_Name,File_Data,Description) " //
+ " values (?,?,?,?) ";
PreparedStatement pstm = conn.prepareStatement(sql);
Long id = this.getMaxAttachmentId(conn) + 1;
pstm.setLong(1, id);
pstm.setString(2, fileName);
pstm.setBlob(3, is);
pstm.setString(4, description);
pstm.executeUpdate();
}
private void closeQuietly(Connection conn) {
try {
if (conn != null) {
conn.close();
}
} catch (Exception e) {
}
}
}
uploadToDB.jsp
<!DOCTYPE >
<html>
<head>
<title>Upload files</title>
</head>
<body>
<div style="padding:5px; color:red;font-style:italic;">
${errorMessage}
</div>
<h2>Upload Files</h2>
<form method="post" action="${pageContext.request.contextPath}/uploadToDB"
enctype="multipart/form-data">
Select file to upload:
<br />
<input type="file" name="file" />
<br />
<input type="file" name="file" />
<br />
Description:
<br />
<input type="text" name="description" size="100" />
<br />
<br />
<input type="submit" value="Upload" />
</form>
</body>
</html>
uploadToDBR.jsp
<!DOCTYPE >
<html>
<head>
<title>Upload files</title>
</head>
<body>
<h3>Upload has been done successfully!</h3>
<a href="${pageContext.request.contextPath}/uploadToDB">Continue Upload</a>
</body>
</html>
Ich hoffe wirklich ich wisst weiter. Danke schonmal im Voraus!
Zuletzt bearbeitet: