/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package io.undertow.attribute;

import io.undertow.server.HttpServerExchange;

/**
 * The query string
 *
 * @author Stuart Douglas
 */
public class QueryStringAttribute implements ExchangeAttribute {

    public static final String QUERY_STRING_SHORT = "%q";
    public static final String QUERY_STRING = "%{QUERY_STRING}";

    public static final ExchangeAttribute INSTANCE = new QueryStringAttribute();

    private QueryStringAttribute() {

    }

    @Override
    public String readAttribute(final HttpServerExchange exchange) {
        return exchange.getQueryString();
    }

    @Override
    public void writeAttribute(final HttpServerExchange exchange, final String newValue) throws ReadOnlyAttributeException {
        exchange.setQueryString(newValue);
    }

    public static final class Builder implements ExchangeAttributeBuilder {

        @Override
        public String name() {
            return "Query String";
        }

        @Override
        public ExchangeAttribute build(final String token) {
            if (token.equals(QUERY_STRING) || token.equals(QUERY_STRING_SHORT)) {
                return QueryStringAttribute.INSTANCE;
            }
            return null;
        }
    }
}

@@ -1250,22 +1250,27 @@
         
-return
+String qs =
  exchang
@@ -1289,16 +1289,101 @@
 ring();%0A
+        if(qs.isEmpty()) %7B%0A            return qs;%0A        %7D%0A        return '?' + qs;%0A
     %7D%0A%0A 

UNDERTOW-299 Include the ? in the query string