[TASK] Refactoring, decoding feature is now in a utility class

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

@@ -25,16 +25,13 @@ package net.sourceforge.plantuml.servlet;
 
 import java.io.IOException;
 import javax.imageio.IIOException;
-import java.net.URLDecoder;
-
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import net.sourceforge.plantuml.FileFormat;
-import net.sourceforge.plantuml.code.Transcoder;
-import net.sourceforge.plantuml.code.TranscoderUtil;
+import net.sourceforge.plantuml.servlet.utility.UmlExtractor;
 
 /**
  * Common service servlet to produce diagram from compressed UML source contained in the end part of the requested URI.
@@ -46,24 +43,7 @@ public abstract class UmlDiagramService extends HttpServlet {
     public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
 
         // build the UML source from the compressed request parameter
-        String text = URLDecoder.decode(getSource(request.getRequestURI()), "UTF-8");
-        Transcoder transcoder = getTranscoder();
-        text = transcoder.decode(text);
-
-        // encapsulate the UML syntax if necessary
-        String uml;
-        if (text.startsWith("@start")) {
-            uml = text;
-        } else {
-            StringBuilder plantUmlSource = new StringBuilder();
-            plantUmlSource.append("@startuml\n");
-            plantUmlSource.append(text);
-            if (text.endsWith("\n") == false) {
-                plantUmlSource.append("\n");
-            }
-            plantUmlSource.append("@enduml");
-            uml = plantUmlSource.toString();
-        }
+        String uml = UmlExtractor.getUmlSource(getSource(request.getRequestURI()));
 
         // generate the response
         DiagramResponse dr = new DiagramResponse(response, getOutputFormat());
@@ -91,7 +71,4 @@ public abstract class UmlDiagramService extends HttpServlet {
      */
     abstract public FileFormat getOutputFormat();
 
-    private Transcoder getTranscoder() {
-        return TranscoderUtil.getDefaultTranscoder();
-    }
 }

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

@@ -0,0 +1,78 @@
+/* ========================================================================
+ * 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;
+
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.net.URLDecoder;
+
+import net.sourceforge.plantuml.code.Transcoder;
+import net.sourceforge.plantuml.code.TranscoderUtil;
+
+/**
+ * Utility class to extract the UML source from the compressed UML source contained in the end part of the requested URI.
+ */
+public class UmlExtractor {
+    
+    /**
+     * Build the complete UML source from the compressed source extracted from the HTTP URI.
+     * 
+     * @param source
+     *            the last part of the URI containing the compressed UML
+     * @return the textual UML source
+     */
+    static public String getUmlSource(String source) {
+
+        // build the UML source from the compressed part of the URL
+        String text;
+        try {
+            text = URLDecoder.decode(source, "UTF-8");
+        } catch (UnsupportedEncodingException uee) {
+            text = "' invalid encoded string";
+        }
+        Transcoder transcoder = TranscoderUtil.getDefaultTranscoder();
+        try {
+            text = transcoder.decode(text);
+        } catch (IOException ioe) {
+            text = "' unable to decode string";
+        }
+
+        // encapsulate the UML syntax if necessary
+        String uml;
+        if (text.startsWith("@start")) {
+            uml = text;
+        } else {
+            StringBuilder plantUmlSource = new StringBuilder();
+            plantUmlSource.append("@startuml\n");
+            plantUmlSource.append(text);
+            if (text.endsWith("\n") == false) {
+                plantUmlSource.append("\n");
+            }
+            plantUmlSource.append("@enduml");
+            uml = plantUmlSource.toString();
+        }
+        return uml;
+    }
+
+}