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58 package org.krysalis.barcode.servlet;
59
60 import java.awt.image.BufferedImage  ;
61 import java.io.ByteArrayOutputStream ;
62 import java.io.IOException ;
63 import javax.servlet.ServletException ;
64 import javax.servlet.http.HttpServlet ;
65 import javax.servlet.http.HttpServletRequest ;
66 import javax.servlet.http.HttpServletResponse ;
67 import javax.xml.transform.Result ;
68 import javax.xml.transform.Source ;
69 import javax.xml.transform.Transformer ;
70 import javax.xml.transform.TransformerFactory ;
71
72 import org.apache.avalon.framework.configuration.Configuration;
73 import org.apache.avalon.framework.configuration.DefaultConfiguration;
74 import org.apache.avalon.framework.logger.ConsoleLogger;
75 import org.apache.avalon.framework.logger.Logger;
76 import org.krysalis.barcode.BarcodeException;
77 import org.krysalis.barcode.BarcodeGenerator;
78 import org.krysalis.barcode.BarcodeUtil;
79 import org.krysalis.barcode.output.bitmap.BitmapCanvasProvider;
80 import org.krysalis.barcode.output.eps.EPSCanvasProvider;
81 import org.krysalis.barcode.output.svg.SVGCanvasProvider;
82 import org.krysalis.barcode.tools.MimeTypes;
83
84
89 public class BarcodeServlet extends HttpServlet {
90
91
92 public static final String BARCODE_MSG = "msg";
93
94 public static final String BARCODE_TYPE = "type";
95
96 public static final String BARCODE_HEIGHT = "height";
97
98 public static final String BARCODE_MODULE_WIDTH = "mw";
99
100 public static final String BARCODE_WIDE_FACTOR = "wf";
101
102 public static final String BARCODE_QUIET_ZONE = "qz";
103
104 public static final String BARCODE_HUMAN_READABLE_POS = "hrp";
105
106 public static final String BARCODE_FORMAT = "fmt";
107
108 public static final String BARCODE_IMAGE_RESOLUTION = "res";
109
110 public static final String BARCODE_IMAGE_GRAYSCALE = "gray";
111
112 private Logger log = new ConsoleLogger(ConsoleLogger.LEVEL_INFO);
113
114
117 protected void doGet(HttpServletRequest request, HttpServletResponse response)
118 throws ServletException , IOException {
119
120 try {
121 String format = determineFormat(request);
122
123 Configuration cfg = buildCfg(request);
124
125 String msg = request.getParameter(BARCODE_MSG);
126 if (msg == null) msg = "0123456789";
127
128 BarcodeUtil util = BarcodeUtil.getInstance();
129 BarcodeGenerator gen = util.createBarcodeGenerator(cfg, log);
130
131 ByteArrayOutputStream bout = new ByteArrayOutputStream (4096);
132 try {
133 if (format.equals(MimeTypes.MIME_SVG)) {
134 SVGCanvasProvider svg = new SVGCanvasProvider(false);
136 try {
137 gen.generateBarcode(svg, msg);
138 } catch (Exception e) {
139 throw new BarcodeException("Error while generating barcode", e);
140 }
141 org.w3c.dom.DocumentFragment frag = svg.getDOMFragment();
142
143 TransformerFactory factory = TransformerFactory.newInstance();
145 Transformer trans = factory.newTransformer();
146 Source src = new javax.xml.transform.dom.DOMSource (frag);
147 Result res = new javax.xml.transform.stream.StreamResult (bout);
148 trans.transform(src, res);
149 } else if (format.equals(MimeTypes.MIME_EPS)) {
150 EPSCanvasProvider eps = new EPSCanvasProvider(bout);
151 gen.generateBarcode(eps, msg);
152 eps.finish();
153 } else {
154 String resText = request.getParameter(BARCODE_IMAGE_RESOLUTION);
155 int resolution = 300; if (resText != null) {
157 resolution = Integer.parseInt(resText);
158 }
159 if (resolution > 2400) {
160 throw new IllegalArgumentException (
161 "Resolutions above 2400dpi are not allowed");
162 }
163 if (resolution < 10) {
164 throw new IllegalArgumentException (
165 "Minimum resolution must be 10dpi");
166 }
167 String gray = request.getParameter(BARCODE_IMAGE_GRAYSCALE);
168 BitmapCanvasProvider bitmap = ("true".equalsIgnoreCase(gray)
169 ? new BitmapCanvasProvider(
170 bout, format, resolution,
171 BufferedImage.TYPE_BYTE_GRAY, true)
172 : new BitmapCanvasProvider(
173 bout, format, resolution,
174 BufferedImage.TYPE_BYTE_BINARY, false));
175 gen.generateBarcode(bitmap, msg);
176 bitmap.finish();
177 }
178 } finally {
179 bout.close();
180 }
181 response.setContentType(format);
182 response.setContentLength(bout.size());
183 response.getOutputStream().write(bout.toByteArray());
184 response.getOutputStream().flush();
185 } catch (Exception e) {
186 log.error("Error while generating barcode", e);
187 throw new ServletException (e);
188 } catch (Throwable t) {
189 log.error("Error while generating barcode", t);
190 throw new ServletException (t);
191 }
192 }
193
194
199 protected String determineFormat(HttpServletRequest request) {
200 String format = request.getParameter(BARCODE_FORMAT);
201 format = MimeTypes.expandFormat(format);
202 if (format == null) format = MimeTypes.MIME_SVG;
203 return format;
204 }
205
206
211 protected Configuration buildCfg(HttpServletRequest request) {
212 DefaultConfiguration cfg = new DefaultConfiguration("barcode");
213 String type = request.getParameter(BARCODE_TYPE);
215 if (type == null) type = "code128";
216 DefaultConfiguration child = new DefaultConfiguration(type);
217 cfg.addChild(child);
218 DefaultConfiguration attr;
220 String height = request.getParameter(BARCODE_HEIGHT);
221 if (height != null) {
222 attr = new DefaultConfiguration("height");
223 attr.setValue(height);
224 child.addChild(attr);
225 }
226 String moduleWidth = request.getParameter(BARCODE_MODULE_WIDTH);
227 if (moduleWidth != null) {
228 attr = new DefaultConfiguration("module-width");
229 attr.setValue(moduleWidth);
230 child.addChild(attr);
231 }
232 String wideFactor = request.getParameter(BARCODE_WIDE_FACTOR);
233 if (wideFactor != null) {
234 attr = new DefaultConfiguration("wide-factor");
235 attr.setValue(wideFactor);
236 child.addChild(attr);
237 }
238 String quietZone = request.getParameter(BARCODE_QUIET_ZONE);
239 if (quietZone != null) {
240 attr = new DefaultConfiguration("quiet-zone");
241 if (quietZone.startsWith("disable")) {
242 attr.setAttribute("enabled", "false");
243 } else {
244 attr.setValue(quietZone);
245 }
246 child.addChild(attr);
247 }
248 String humanReadable = request.getParameter(BARCODE_HUMAN_READABLE_POS);
249 if (humanReadable != null) {
250 attr = new DefaultConfiguration("human-readable");
251 attr.setValue(humanReadable);
252 child.addChild(attr);
253 }
254 return cfg;
255 }
256
257 }
258 |
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