diff --git a/lucene/join/src/java/org/apache/lucene/search/join/FakeScorer.java b/lucene/join/src/java/org/apache/lucene/search/join/FakeScorer.java
new file mode 100644
index 00000000000..d4b02dc7d00
--- /dev/null
+++ b/lucene/join/src/java/org/apache/lucene/search/join/FakeScorer.java
@@ -0,0 +1,75 @@
+package org.apache.lucene.search.join;
+
+/*
+ * 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.
+ */
+
+import java.util.Collection;
+
+import org.apache.lucene.search.Collector;
+import org.apache.lucene.search.Scorer;
+import org.apache.lucene.search.Weight;
+
+/** Passed to {@link Collector#setScorer} during join collection. */
+final class FakeScorer extends Scorer {
+  float score;
+  int doc = -1;
+  int freq = 1;
+
+  public FakeScorer() {
+    super(null);
+  }
+    
+  @Override
+  public int advance(int target) {
+    throw new UnsupportedOperationException("FakeScorer doesn't support advance(int)");
+  }
+
+  @Override
+  public int docID() {
+    return doc;
+  }
+
+  @Override
+  public int freq() {
+    throw new UnsupportedOperationException("FakeScorer doesn't support freq()");
+  }
+
+  @Override
+  public int nextDoc() {
+    throw new UnsupportedOperationException("FakeScorer doesn't support nextDoc()");
+  }
+    
+  @Override
+  public float score() {
+    return score;
+  }
+
+  @Override
+  public long cost() {
+    return 1;
+  }
+
+  @Override
+  public Weight getWeight() {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public Collection<ChildScorer> getChildren() {
+    throw new UnsupportedOperationException();
+  }
+}