[FEATURE] Map usage integrated in the interactive servlet

JSTL (without EL) added

pom.xml

@@ -75,6 +75,11 @@
       <artifactId>plantuml</artifactId>
       <version>LATEST</version>
     </dependency>
+    <dependency>
+      <groupId>javax.servlet</groupId>
+      <artifactId>jstl</artifactId>
+      <version>1.2</version>
+    </dependency>
     <dependency>
       <groupId>HTTPClient</groupId>
       <artifactId>HTTPClient</artifactId>

src/main/java/net/sourceforge/plantuml/servlet/PlantUmlServlet.java

@@ -42,6 +42,7 @@ import net.sourceforge.plantuml.SourceStringReader;
 import net.sourceforge.plantuml.StringUtils;
 import net.sourceforge.plantuml.code.Transcoder;
 import net.sourceforge.plantuml.code.TranscoderUtil;
+import net.sourceforge.plantuml.servlet.utility.SourceInformation;
 import HTTPClient.CookieModule;
 import HTTPClient.HTTPConnection;
 import HTTPClient.HTTPResponse;
@@ -142,6 +143,11 @@ public class PlantUmlServlet extends HttpServlet {
         request.setAttribute("net.sourceforge.plantuml.servlet.decoded", text);
         request.setAttribute("net.sourceforge.plantuml.servlet.encoded", encoded);
         
+        // check if an image map is necessary
+        if (text != null && SourceInformation.containsLink(text)) {
+            request.setAttribute("net.sourceforge.plantuml.servlet.mapneeded", Boolean.TRUE);
+        }    
+
         // forward to index.jsp
         RequestDispatcher dispatcher = request.getRequestDispatcher("/index.jsp");
         dispatcher.forward(request, response);

src/main/java/net/sourceforge/plantuml/servlet/utility/SourceInformation.java

@@ -0,0 +1,40 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * Project Info:  http://plantuml.sourceforge.net
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ */
+package net.sourceforge.plantuml.servlet.utility;
+
+/**
+ * Utility class giving information about a diagram based on its source description.
+ */
+public class SourceInformation {
+    /*
+     * Check if there is a link ([[url]]) in the source of the diagram.
+     * @param source the full textual representation of a diagram
+     * @return true if there is at least one link
+     */
+    public static boolean containsLink(String source) {
+        // TODO build a better implementation
+        return source.contains("[[");
+    }
+
+}

src/main/java/net/sourceforge/plantuml/servlet/utility/package.html

@@ -4,6 +4,7 @@
 <ul>
 <li>NullOutputStream is used by the Map feature.</li>
 <li>UmlExtractor encapsulates the PlantUML library to decode the UML compressed source.</li>
+<li>SourceInformation extracts useful information from the full textual source.</li>
 </ul>
 </body>
 </html>

src/main/webapp/index.jsp

@@ -1,5 +1,5 @@
 <%@ page info="index" contentType="text/html; charset=utf-8" pageEncoding="utf-8" session="false" %>
-
+<%@ taglib uri="http://java.sun.com/jstl/core_rt" prefix="c" %>
 <%
 String contextRoot = request.getContextPath();
 String host = "http://" + request.getServerName() + ":" + request.getServerPort();
@@ -8,6 +8,8 @@ String umltext = "";
 String imgurl = "";
 String svgurl = "";
 String txturl = "";
+String mapurl = "";
+Object mapNeeded = request.getAttribute("net.sourceforge.plantuml.servlet.mapneeded");
 Object encodedAttribute = request.getAttribute("net.sourceforge.plantuml.servlet.encoded");
 if (encodedAttribute != null) {
     encoded = encodedAttribute.toString();
@@ -15,6 +17,9 @@ if (encodedAttribute != null) {
 	    imgurl = host + contextRoot + "/img/" + encoded;
 	    svgurl = host + contextRoot + "/svg/" + encoded;
 	    txturl = host + contextRoot + "/txt/" + encoded;
+        if (mapNeeded != null) {
+            mapurl = host + contextRoot + "/map/" + encoded;
+        }
 	}
 }
 Object decodedAttribute = request.getAttribute("net.sourceforge.plantuml.servlet.decoded");
@@ -59,12 +64,19 @@ if (decodedAttribute != null) {
             <input type="submit"/>
         </p>
     </form>
-    <% if ( !imgurl.isEmpty()) { %>
+    <% if (!imgurl.isEmpty()) { %>
     <hr/>
     <a href="<%=svgurl%>">View as SVG</a>&nbsp;
     <a href="<%=txturl%>">View as ASCII Art</a>
     <p id="diagram">
-        <img src="<%=imgurl %>" alt="PlantUML diagram"/>
+        <% if (mapNeeded != null) { %>
+        <img src="<%=imgurl %>" alt="PlantUML diagram" usemap="#umlmap" />
+        <map name="umlmap">
+            <c:import url="<%=mapurl %>" />
+        </map>
+        <% } else { %>
+        <img src="<%=imgurl %>" alt="PlantUML diagram" />
+        <% } %>
     </p>
     <% } //endif %>
 </div>

src/test/java/net/sourceforge/plantuml/servlet/TestForm.java

@@ -1,6 +1,7 @@
 package net.sourceforge.plantuml.servlet;
 
 import com.meterware.httpunit.GetMethodWebRequest;
+import com.meterware.httpunit.HTMLElement;
 import com.meterware.httpunit.WebConversation;
 import com.meterware.httpunit.WebForm;
 import com.meterware.httpunit.WebRequest;
@@ -113,4 +114,23 @@ public class TestForm extends WebappTestCase {
         assertEquals(1, response.getImages().length);
     }
 
+    /**
+     * Verifies that an image map is produced if the diagram contains a link
+     */
+    public void testImageMap() throws Exception {
+        WebConversation conversation = new WebConversation();
+        // Fill the form and submit it
+        WebRequest request = new GetMethodWebRequest(getServerUrl());
+        WebResponse response = conversation.getResponse(request);
+        WebForm formText = response.getForms()[0];
+        formText.setParameter("text", "@startuml \nBob -> Alice : [[http://yahoo.com]] Hello \n@enduml");
+        response = formText.submit();
+        // Analyze response
+        // Ensure the generated image is present
+        assertEquals(1, response.getImages().length);
+        // Ensure the image map is present
+        HTMLElement maps[] = response.getElementsByTagName("map");
+        assertEquals(1, maps.length);
+    }
+
 }