Expose LimitTokenCountFilter as a TokenFilter

Closes #3013

src/main/java/org/elasticsearch/index/analysis/AnalysisModule.java

@@ -437,6 +437,7 @@ public class AnalysisModule extends AbstractModule {
             tokenFiltersBindings.processTokenFilter("unique", UniqueTokenFilterFactory.class);
             tokenFiltersBindings.processTokenFilter("truncate", TruncateTokenFilterFactory.class);
             tokenFiltersBindings.processTokenFilter("trim", TrimTokenFilterFactory.class);
+            tokenFiltersBindings.processTokenFilter("limit", LimitTokenCountFilterFactory.class);
         }
 
         @Override

src/main/java/org/elasticsearch/index/analysis/LimitTokenCountFilterFactory.java

@@ -0,0 +1,50 @@
+/*
+ * Licensed to ElasticSearch and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. ElasticSearch 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.
+ */
+
+package org.elasticsearch.index.analysis;
+
+import org.apache.lucene.analysis.TokenStream;
+import org.apache.lucene.analysis.miscellaneous.LimitTokenCountFilter;
+import org.elasticsearch.common.inject.Inject;
+import org.elasticsearch.common.inject.assistedinject.Assisted;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
+import org.elasticsearch.index.Index;
+import org.elasticsearch.index.settings.IndexSettings;
+
+/**
+ *
+ */
+public class LimitTokenCountFilterFactory extends AbstractTokenFilterFactory {
+
+  final int maxTokenCount;
+  final boolean consumeAllTokens;
+
+    @Inject
+    public LimitTokenCountFilterFactory(Index index, @IndexSettings Settings indexSettings, Environment env, @Assisted String name, @Assisted Settings settings) {
+        super(index, indexSettings, name, settings);
+        this.maxTokenCount = settings.getAsInt("max_token_count", 1);
+        this.consumeAllTokens = settings.getAsBoolean("consume_all_tokens", false);
+    }
+
+    @Override
+    public TokenStream create(TokenStream tokenStream) {
+        return new LimitTokenCountFilter(tokenStream, maxTokenCount, consumeAllTokens);
+    }
+}