2 * Copyright 2008 ZXing authors
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 package com.google.zxing.web;
19 import com.google.zxing.DecodeHintType;
20 import com.google.zxing.MultiFormatReader;
21 import com.google.zxing.Reader;
22 import com.google.zxing.ReaderException;
23 import com.google.zxing.Result;
24 import com.google.zxing.client.j2se.BufferedImageMonochromeBitmapSource;
25 import com.google.zxing.client.result.ParsedResult;
26 import com.google.zxing.client.result.ResultParser;
27 import org.apache.commons.fileupload.FileItem;
28 import org.apache.commons.fileupload.FileUploadException;
29 import org.apache.commons.fileupload.disk.DiskFileItemFactory;
30 import org.apache.commons.fileupload.servlet.ServletFileUpload;
31 import org.apache.commons.lang.StringEscapeUtils;
32 import org.apache.http.Header;
33 import org.apache.http.HttpException;
34 import org.apache.http.HttpMessage;
35 import org.apache.http.HttpResponse;
36 import org.apache.http.HttpVersion;
37 import org.apache.http.client.HttpClient;
38 import org.apache.http.client.methods.HttpGet;
39 import org.apache.http.conn.scheme.PlainSocketFactory;
40 import org.apache.http.conn.scheme.Scheme;
41 import org.apache.http.conn.scheme.SchemeRegistry;
42 import org.apache.http.conn.ssl.SSLSocketFactory;
43 import org.apache.http.impl.client.DefaultHttpClient;
44 import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
45 import org.apache.http.params.BasicHttpParams;
46 import org.apache.http.params.HttpParams;
47 import org.apache.http.params.HttpProtocolParams;
49 import javax.imageio.ImageIO;
50 import javax.servlet.ServletConfig;
51 import javax.servlet.ServletException;
52 import javax.servlet.http.HttpServlet;
53 import javax.servlet.http.HttpServletRequest;
54 import javax.servlet.http.HttpServletResponse;
55 import java.awt.image.BufferedImage;
56 import java.io.IOException;
57 import java.io.InputStream;
58 import java.io.OutputStreamWriter;
59 import java.io.Writer;
60 import java.net.SocketException;
62 import java.net.URISyntaxException;
63 import java.net.UnknownHostException;
64 import java.util.Hashtable;
65 import java.util.List;
66 import java.util.logging.Logger;
69 * {@link HttpServlet} which decodes images containing barcodes. Given a URL, it will
70 * retrieve the image and decode it. It can also process image files uploaded via POST.
74 public final class DecodeServlet extends HttpServlet {
76 private static final long MAX_IMAGE_SIZE = 500000L;
78 private static final Logger log = Logger.getLogger(DecodeServlet.class.getName());
80 static final Hashtable<DecodeHintType, Object> HINTS;
83 HINTS = new Hashtable<DecodeHintType, Object>(3);
84 HINTS.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
87 private HttpClient client;
88 private DiskFileItemFactory diskFileItemFactory;
91 public void init(ServletConfig servletConfig) {
93 Logger logger = Logger.getLogger("com.google.zxing");
94 logger.addHandler(new ServletContextLogHandler(servletConfig.getServletContext()));
96 HttpParams params = new BasicHttpParams();
97 HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
99 SchemeRegistry registry = new SchemeRegistry();
100 registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
101 registry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
103 client = new DefaultHttpClient(new ThreadSafeClientConnManager(params, registry), params);
105 diskFileItemFactory = new DiskFileItemFactory();
107 log.info("DecodeServlet configured");
111 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
113 String imageURIString = request.getParameter("u");
114 if (imageURIString == null || imageURIString.length() == 0) {
115 response.sendRedirect("badurl.jspx");
119 if (!(imageURIString.startsWith("http://") || imageURIString.startsWith("https://"))) {
120 imageURIString = "http://" + imageURIString;
125 imageURI = new URI(imageURIString);
126 } catch (URISyntaxException urise) {
127 response.sendRedirect("badurl.jspx");
131 HttpGet getRequest = new HttpGet(imageURI);
134 HttpResponse getResponse = client.execute(getRequest);
135 if (getResponse.getStatusLine().getStatusCode() != HttpServletResponse.SC_OK) {
136 response.sendRedirect("badurl.jspx");
139 if (!isSizeOK(getResponse)) {
140 response.sendRedirect("badimage.jspx");
143 log.info("Decoding " + imageURI);
144 InputStream is = getResponse.getEntity().getContent();
146 processStream(is, request, response);
150 } catch (IllegalArgumentException iae) {
151 // Thrown if hostname is bad or null
153 response.sendRedirect("badurl.jspx");
154 } catch (SocketException se) {
155 // Thrown if hostname is bad or null
157 response.sendRedirect("badurl.jspx");
158 } catch (HttpException he) {
160 response.sendRedirect("badurl.jspx");
161 } catch (UnknownHostException uhe) {
163 response.sendRedirect("badurl.jspx");
169 protected void doPost(HttpServletRequest request, HttpServletResponse response)
170 throws ServletException, IOException {
172 if (!ServletFileUpload.isMultipartContent(request)) {
173 response.sendRedirect("badimage.jspx");
177 ServletFileUpload upload = new ServletFileUpload(diskFileItemFactory);
178 upload.setFileSizeMax(MAX_IMAGE_SIZE);
182 for (FileItem item : (List<FileItem>) upload.parseRequest(request)) {
183 if (!item.isFormField()) {
184 if (item.getSize() <= MAX_IMAGE_SIZE) {
185 log.info("Decoding uploaded file");
186 InputStream is = item.getInputStream();
188 processStream(is, request, response);
193 response.sendRedirect("badimage.jspx");
198 } catch (FileUploadException fue) {
199 response.sendRedirect("badimage.jspx");
204 private static void processStream(InputStream is, HttpServletRequest request, HttpServletResponse response)
205 throws ServletException, IOException {
206 BufferedImage image = ImageIO.read(is);
208 response.sendRedirect("badimage.jspx");
212 Reader reader = new MultiFormatReader();
215 result = reader.decode(new BufferedImageMonochromeBitmapSource(image), HINTS);
216 } catch (ReaderException re) {
217 log.info("DECODE FAILED: " + re.toString());
218 response.sendRedirect("notfound.jspx");
222 if (request.getParameter("full") == null) {
223 response.setContentType("text/plain");
224 response.setCharacterEncoding("UTF8");
225 Writer out = new OutputStreamWriter(response.getOutputStream(), "UTF8");
227 out.write(result.getText());
232 request.setAttribute("result", result);
233 byte[] rawBytes = result.getRawBytes();
234 if (rawBytes != null) {
235 request.setAttribute("rawBytesString", arrayToString(rawBytes));
237 request.setAttribute("rawBytesString", "(Not applicable)");
239 String text = result.getText();
241 request.setAttribute("text", StringEscapeUtils.escapeXml(text));
243 request.setAttribute("text", "(Not applicable)");
245 ParsedResult parsedResult = ResultParser.parseResult(result);
246 request.setAttribute("parsedResult", parsedResult);
247 String displayResult = parsedResult.getDisplayResult();
248 if (displayResult != null) {
249 request.setAttribute("displayResult", StringEscapeUtils.escapeXml(displayResult));
251 request.setAttribute("displayResult", "(Not applicable)");
253 request.getRequestDispatcher("decoderesult.jspx").forward(request, response);
257 private static boolean isSizeOK(HttpMessage getResponse) {
258 Header lengthHeader = getResponse.getLastHeader("Content-Length");
259 if (lengthHeader != null) {
260 long length = Long.parseLong(lengthHeader.getValue());
261 if (length > MAX_IMAGE_SIZE) {
268 private static String arrayToString(byte[] bytes) {
269 int length = bytes.length;
270 StringBuilder result = new StringBuilder(length << 2);
273 int max = Math.min(i + 8, length);
274 for (int j = i; j < max; j++) {
275 int value = bytes[j] & 0xFF;
276 result.append(Integer.toHexString(value / 16));
277 result.append(Integer.toHexString(value % 16));
283 for (int j = i - 8; j < length; j++) {
284 result.append(Integer.toHexString(bytes[j] & 0xFF));
287 return result.toString();
291 public void destroy() {
292 log.config("DecodeServlet shutting down...");