Enhanced HTML extension (moved StatusInfoConverter). Issue #1005.

build/tmpl/text/changes.txt

@@ -7,6 +7,7 @@ Changes log
     - API changes
        - Removed lesser used/maintained extensions (JDBC, JiBX, jSSLUtils, 
          ROME, SIP, WebDAV, XDB, XStream).
+       - Enhanced HTML extension (moved StatusInfoConverter). Issue #1005.
     - Bugs
        - Reintroduced registration by default of the internal HTTP server 
          connectors in JEE edition.

modules/org.restlet.ext.html/src/org/restlet/ext/html/HtmlConverter.java

@@ -27,27 +27,45 @@
 import java.io.IOException;
 import java.util.List;
 
+import org.restlet.Request;
+import org.restlet.Response;
 import org.restlet.data.MediaType;
 import org.restlet.data.Preference;
+import org.restlet.data.Status;
+import org.restlet.engine.application.StatusInfo;
 import org.restlet.engine.converter.ConverterHelper;
 import org.restlet.engine.resource.VariantInfo;
+import org.restlet.engine.util.StringUtils;
 import org.restlet.representation.Representation;
+import org.restlet.representation.StringRepresentation;
 import org.restlet.representation.Variant;
 import org.restlet.resource.Resource;
+import org.restlet.service.StatusService;
 
 /**
- * Converter between the HTML API and Representation classes.
+ * Converter between the HTML API and Representation classes. It handles the
+ * case of the web formular, and the HTTP status.
  * 
  * @author Jerome Louvel
+ * @author Manuel Boillod
  */
 public class HtmlConverter extends ConverterHelper {
-
+    /** Variant with media type multipart/form-data. */
     private static final VariantInfo VARIANT_MULTIPART = new VariantInfo(
             MediaType.MULTIPART_FORM_DATA);
 
+    /** Variant with media type application/x-www-form-urlencoded. */
     private static final VariantInfo VARIANT_WWW_FORM = new VariantInfo(
             MediaType.APPLICATION_WWW_FORM);
 
+    /** Variant with media type application/xhtml+xml. */
+    private static final VariantInfo VARIANT_APPLICATION_XHTML = new VariantInfo(
+            MediaType.APPLICATION_XHTML);
+
+    /** Variant with media type text/html. */
+    private static final VariantInfo VARIANT_TEXT_HTML = new VariantInfo(
+            MediaType.TEXT_HTML);
+
     @Override
     public List<Class<?>> getObjectClasses(Variant source) {
         List<Class<?>> result = null;
@@ -56,23 +74,59 @@ public List<Class<?>> getObjectClasses(Variant source) {
             result = addObjectClass(result, FormDataSet.class);
         } else if (VARIANT_MULTIPART.isCompatible(source)) {
             result = addObjectClass(result, FormDataSet.class);
+        } else if (isHtmlCompatible(source)) {
+            result = addObjectClass(result, StatusInfo.class);
         }
 
         return result;
     }
 
+    /**
+     * Returns the status information to display in the default representation.
+     * By default it returns the status's reason phrase.
+     * 
+     * @param status
+     *            The status.
+     * @return The status information.
+     * @see StatusService#toRepresentation(Status, Request, Response)
+     */
+    protected String getStatusLabel(StatusInfo status) {
+        return (status.getReasonPhrase() != null) ? status.getReasonPhrase()
+                : "No information available for this result status";
+    }
+
     @Override
     public List<VariantInfo> getVariants(Class<?> source) {
         List<VariantInfo> result = null;
 
-        if (FormDataSet.class.isAssignableFrom(source)) {
-            result = addVariant(result, VARIANT_WWW_FORM);
-            result = addVariant(result, VARIANT_MULTIPART);
+        if (source != null) {
+            if (FormDataSet.class.isAssignableFrom(source)) {
+                result = addVariant(result, VARIANT_WWW_FORM);
+                result = addVariant(result, VARIANT_MULTIPART);
+            } else if (StatusInfo.class.isAssignableFrom(source)) {
+                result = addVariant(result, VARIANT_TEXT_HTML);
+                result = addVariant(result, VARIANT_APPLICATION_XHTML);
+            }
         }
 
         return result;
     }
 
+    /**
+     * Indicates if the given variant is compatible with the media types
+     * supported by this converter.
+     * 
+     * @param variant
+     *            The variant.
+     * @return True if the given variant is compatible with the media types
+     *         supported by this converter.
+     */
+    protected boolean isHtmlCompatible(Variant variant) {
+        return (variant != null)
+                && (VARIANT_TEXT_HTML.isCompatible(variant) || VARIANT_APPLICATION_XHTML
+                        .isCompatible(variant));
+    }
+
     @Override
     public float score(Object source, Variant target, Resource resource) {
         float result = -1.0F;
@@ -88,6 +142,8 @@ public float score(Object source, Variant target, Resource resource) {
             } else {
                 result = 0.5F;
             }
+        } else if (source instanceof StatusInfo && isHtmlCompatible(target)) {
+            result = 1.0F;
         }
 
         return result;
@@ -114,6 +170,55 @@ public <T> float score(Representation source, Class<T> target,
         return result;
     }
 
+    /**
+     * Returns a representation for the given status.<br>
+     * In order to customize the default representation, this method can be
+     * overridden.
+     * 
+     * @param status
+     *            The status info to represent.
+     * @return The representation of the given status.
+     */
+    protected Representation toHtml(StatusInfo status) {
+        final StringBuilder sb = new StringBuilder();
+        sb.append("<html>\n");
+        sb.append("<head>\n");
+        sb.append("   <title>Status page</title>\n");
+        sb.append("</head>\n");
+        sb.append("<body style=\"font-family: sans-serif;\">\n");
+
+        sb.append("<p style=\"font-size: 1.2em;font-weight: bold;margin: 1em 0px;\">");
+        sb.append(StringUtils.htmlEscape(getStatusLabel(status)));
+        sb.append("</p>\n");
+        if (status.getDescription() != null) {
+            sb.append("<p>");
+            sb.append(StringUtils.htmlEscape(status.getDescription()));
+            sb.append("</p>\n");
+        }
+
+        sb.append("<p>You can get technical details <a href=\"");
+        sb.append(status.getUri());
+        sb.append("\">here</a>.<br>\n");
+
+        if (status.getContactEmail() != null) {
+            sb.append("For further assistance, you can contact the <a href=\"mailto:");
+            sb.append(status.getContactEmail());
+            sb.append("\">administrator</a>.<br>\n");
+        }
+
+        if (status.getHomeRef() != null) {
+            sb.append("Please continue your visit at our <a href=\"");
+            sb.append(status.getHomeRef());
+            sb.append("\">home page</a>.\n");
+        }
+
+        sb.append("</p>\n");
+        sb.append("</body>\n");
+        sb.append("</html>\n");
+
+        return new StringRepresentation(sb.toString(), MediaType.TEXT_HTML);
+    }
+
     @SuppressWarnings("unchecked")
     @Override
     public <T> T toObject(Representation source, Class<T> target,
@@ -134,8 +239,11 @@ public Representation toRepresentation(Object source, Variant target,
 
         if (source instanceof FormDataSet) {
             result = (FormDataSet) source;
+        } else if (source != null
+                && StatusInfo.class.isAssignableFrom(source.getClass())) {
+            StatusInfo si = (StatusInfo) source;
+            result = toHtml(si);
         }
-
         return result;
     }
 
@@ -144,6 +252,10 @@ public <T> void updatePreferences(List<Preference<MediaType>> preferences,
             Class<T> entity) {
         if (FormDataSet.class.isAssignableFrom(entity)) {
             updatePreferences(preferences, MediaType.APPLICATION_WWW_FORM, 1.0F);
+        } else if (StatusInfo.class.isAssignableFrom(entity)) {
+            updatePreferences(preferences, MediaType.APPLICATION_XHTML, 1.0F);
+            updatePreferences(preferences, MediaType.TEXT_HTML, 1.0F);
+
         }
     }