--- /dev/null
+package org.apache.lucene.queryParser.core.config;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+
+/**
+ * An instance of this class represents a key that is used to retrieve a value
+ * from {@link AbstractQueryConfig}. It also holds the value's type, which is
+ * defined in the generic argument.
+ *
+ * @see AbstractQueryConfig
+ */
+final public class ConfigurationKey<T> {
+
+ private ConfigurationKey() {}
+
+ /**
+ * Creates a new instance.
+ *
+ * @param <T> the value's type
+ *
+ * @return a new instance
+ */
+ public static <T> ConfigurationKey<T> newInstance() {
+ return new ConfigurationKey<T>();
+ }
+
+}