Prefer HTTP constants

Author: gaul

src/main/java/org/gaul/httpbin/HttpBinHandler.java

@@ -89,7 +89,8 @@ private void handleHelper(Request baseRequest, HttpServletRequest request,
                     status = Integer.parseInt(uri.substring(
                             "/status/".length()));
                 } catch (NumberFormatException nfe) {
-                    servletResponse.setStatus(400);
+                    servletResponse.setStatus(
+                            HttpServletResponse.SC_BAD_REQUEST);
                     baseRequest.setHandled(true);
                     return;
                 }
@@ -278,7 +279,8 @@ baos, new Deflater(Deflater.DEFAULT_COMPRESSION,
                         request, "duration", 0.0));
                 int numBytes = Utils.getIntParameter(request, "numbytes", 10);
                 if (numBytes <= 0) {
-                    servletResponse.setStatus(400);
+                    servletResponse.setStatus(
+                            HttpServletResponse.SC_BAD_REQUEST);
                     baseRequest.setHandled(true);
                     return;
                 }