Add eviction configuration for the Map.

Author: akuksin

spring-boot/hazelcast/hazelcast-embeded-cache/src/main/java/io/refectoring/cache/embedded/HazelcastNode.java

@@ -1,7 +1,6 @@
 package io.refectoring.cache.embedded;
 
-import com.hazelcast.config.Config;
-import com.hazelcast.config.MapConfig;
+import com.hazelcast.config.*;
 import com.hazelcast.core.Hazelcast;
 import com.hazelcast.core.HazelcastInstance;
 import com.hazelcast.map.IMap;
@@ -16,7 +15,7 @@ public class HazelcastNode {
 
     public String put(String number, Car car){
         IMap<Object, Object> map = hzInstance.getMap(CARS);
-        return (String) map.put(number, car);
+        return (String) map.putIfAbsent(number, car);
     }
 
     public Car get(String key){
@@ -26,10 +25,22 @@ public Car get(String key){
 
     public Config createConfig() {
         Config config = new Config();
+        config.addMapConfig(mapConfig());
+        return config;
+    }
+
+    private MapConfig mapConfig() {
         MapConfig mapConfig = new MapConfig(CARS);
+        mapConfig.setEvictionConfig(evictionConfig());
         mapConfig.setTimeToLiveSeconds(20);
         mapConfig.setMaxIdleSeconds(360);
-        config.addMapConfig(mapConfig);
-        return config;
+        return mapConfig;
+    }
+
+    private EvictionConfig evictionConfig() {
+        EvictionConfig evictionConfig = new EvictionConfig();
+        evictionConfig.setEvictionPolicy(EvictionPolicy.LFU);
+        evictionConfig.setSize(2000);
+        return evictionConfig;
     }
 }