fix[cache]: Comparison method violates its general contract

protocol/src/main/java/com/zfoo/protocol/model/Pair.java

@@ -74,7 +74,7 @@ public class Pair<K, V> {
 
     @Override
     public int hashCode() {
-        return Objects.hash(key, value);
+        return Objects.hashCode(key);
     }
 
     @Override

protocol/src/main/java/com/zfoo/protocol/model/PairLong.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2020 The zfoo Authors
+ * Licensed 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 com.zfoo.protocol.model;
+
+
+import java.util.Objects;
+
+/**
+ * 键值对对象，只能在构造时传入键值
+ *
+ * @param <V> 值类型
+ * @author godotg
+ */
+public class PairLong<V> {
+
+    private long key;
+    private V value;
+
+    public PairLong() {
+
+    }
+
+    /**
+     * 构造
+     *
+     * @param key   键
+     * @param value 值
+     */
+    public PairLong(long key, V value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    /**
+     * 获取键
+     *
+     * @return 键
+     */
+    public long getKey() {
+        return this.key;
+    }
+
+    /**
+     * 获取值
+     *
+     * @return 值
+     */
+    public V getValue() {
+        return this.value;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        PairLong<?> pairLong = (PairLong<?>) o;
+        return key == pairLong.key && Objects.equals(value, pairLong.value);
+    }
+
+    @Override
+    public int hashCode() {
+        return Long.hashCode(key);
+    }
+
+    @Override
+    public String toString() {
+        return "Pair [key=" + key + ", value=" + value + "]";
+    }
+}