SOLR-7757: Don't use pair from jfxrt.jar - this library is optional in some OS's.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1695075 13f79535-47bb-0310-9956-ffa450edef68

solr/solrj/src/java/org/apache/solr/common/cloud/ZkStateReader.java

@@ -33,10 +33,10 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.TimeUnit;
 
-import javafx.util.Pair;
 import org.apache.solr.common.Callable;
 import org.apache.solr.common.SolrException;
 import org.apache.solr.common.SolrException.ErrorCode;
+import org.apache.solr.common.util.Pair;
 import org.apache.solr.common.util.Utils;
 import org.apache.zookeeper.CreateMode;
 import org.apache.zookeeper.KeeperException;

solr/solrj/src/java/org/apache/solr/common/util/Pair.java

@@ -0,0 +1,39 @@
+package org.apache.solr.common.util;
+
+/*
+ * 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.io.Serializable;
+
+public class Pair<K, V> implements Serializable {
+  private K key;
+
+  public K getKey() {
+    return key;
+  }
+
+  private V value;
+
+  public V getValue() {
+    return value;
+  }
+
+  public Pair(K key, V value) {
+    this.key = key;
+    this.value = value;
+  }
+}