--- /dev/null
+package org.apache.lucene.search.payloads;
+
+import org.apache.lucene.search.Explanation;
+/**
+ * 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.
+ */
+
+/**
+ * Calculates the minimum payload seen
+ *
+ **/
+public class MinPayloadFunction extends PayloadFunction {
+
+ @Override
+ public float currentScore(int docId, String field, int start, int end, int numPayloadsSeen, float currentScore, float currentPayloadScore) {
+ if (numPayloadsSeen == 0) {
+ return currentPayloadScore;
+ } else {
+ return Math.min(currentPayloadScore, currentScore);
+ }
+ }
+
+ @Override
+ public float docScore(int docId, String field, int numPayloadsSeen, float payloadScore) {
+ return numPayloadsSeen > 0 ? payloadScore : 1;
+ }
+
+ @Override
+ public Explanation explain(int doc, int numPayloadsSeen, float payloadScore) {
+ Explanation expl = new Explanation();
+ float minPayloadScore = (numPayloadsSeen > 0 ? payloadScore : 1);
+ expl.setValue(minPayloadScore);
+ expl.setDescription("MinPayloadFunction(...)");
+ return expl;
+ }
+ @Override
+ public int hashCode() {
+ final int prime = 31;
+ int result = 1;
+ result = prime * result + this.getClass().hashCode();
+ return result;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj)
+ return true;
+ if (obj == null)
+ return false;
+ if (getClass() != obj.getClass())
+ return false;
+ return true;
+ }
+
+}