add custom Jetty errorhandler

to provide custom error page footer line
- remove redundant mime check in UrlProxyServlet

source/net/yacy/http/Jetty8HttpServerImpl.java

@@ -108,6 +108,7 @@ public class Jetty8HttpServerImpl implements YaCyHttpServer {
         WebAppContext htrootContext = new WebAppContext();
         htrootContext.setContextPath("/");
         String htrootpath = sb.getConfig(SwitchboardConstants.HTROOT_PATH, SwitchboardConstants.HTROOT_PATH_DEFAULT);
+        htrootContext.setErrorHandler(new YaCyErrorHandler()); // handler for custom error page
         try {
             htrootContext.setBaseResource(Resource.newResource(htrootpath));
 

source/net/yacy/http/YaCyErrorHandler.java

@@ -0,0 +1,53 @@
+//
+//  YaCyErrorHandler
+//  ----------------
+//  Copyright 2014 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
+//  First released 2014 at http://yacy.net
+//
+//  $LastChangedDate$
+//  $LastChangedRevision$
+//  $LastChangedBy$
+//
+//  This library is free software; you can redistribute it and/or
+//  modify it under the terms of the GNU Lesser General Public
+//  License as published by the Free Software Foundation; either
+//  version 2.1 of the License, or (at your option) any later version.
+//
+//  This library is 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 Lesser General Public License
+//  along with this program in the file lgpl21.txt
+//  If not, see <http://www.gnu.org/licenses/>.
+//
+
+package net.yacy.http;
+
+import java.io.IOException;
+import java.io.Writer;
+import javax.servlet.http.HttpServletRequest;
+import net.yacy.peers.operation.yacyBuildProperties;
+import org.eclipse.jetty.server.handler.ErrorHandler;
+
+/**
+ * Custom Handler to serve error pages called by the HttpResponse.sendError method
+ */
+public class YaCyErrorHandler extends ErrorHandler {
+
+    @Override
+    protected void writeErrorPageBody(HttpServletRequest request, Writer writer, int code, String message, boolean showStacks)
+            throws IOException {
+        String uri = request.getRequestURI();
+
+        writeErrorPageMessage(request, writer, code, message, uri);
+        if (showStacks) {
+            writeErrorPageStacks(request, writer);
+        }
+        writer.write("<br/><hr /><small>YaCy " + yacyBuildProperties.getVersion() + "  - <i> powered by Jetty </i> - </small>");
+        for (int i = 0; i < 20; i++) {
+            writer.write("<br/>                                \n");
+        }
+    }
+}

source/net/yacy/http/servlets/UrlProxyServlet.java

@@ -195,7 +195,7 @@ public class UrlProxyServlet extends ProxyServlet implements Servlet {
             response.setStatus(httpStatus);
             response.setContentType(mimeType);
             
-            if ((httpStatus == HttpServletResponse.SC_OK) &&(mimeType != null) && (mimeType.startsWith("text/html") || mimeType.startsWith("text"))) {
+            if ((httpStatus == HttpServletResponse.SC_OK) && (mimeType != null) && mimeType.startsWith("text")) {
                 if (proxyResponseHeader.containsKey(HeaderFramework.TRANSFER_ENCODING) && proxyResponseHeader.get(HeaderFramework.TRANSFER_ENCODING).contains("chunked")) {
                      proxyout = new ChunkedInputStream(proxyout);
                 }