Added Junit test for DynamicServerListLoadBalancer

ribbon-core/src/test/java/com/netflix/loadbalancer/DynamicServerListLoadBalancerTest.java

+/*
+ *
+ * Copyright 2014 Netflix, Inc.
+ *
+ * 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.netflix.loadbalancer;
+
+import static org.junit.Assert.*;
+
+import java.util.List;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.Test;
+
+import com.google.common.collect.Lists;
+import com.netflix.client.config.CommonClientConfigKey;
+import com.netflix.client.config.DefaultClientConfigImpl;
+import com.netflix.client.config.IClientConfig;
+
+public class DynamicServerListLoadBalancerTest {
+    public static class MyServerList extends AbstractServerList<Server> {
+
+        public final static CountDownLatch latch = new CountDownLatch(5);
+        
+        public static final List<Server> list = Lists.newArrayList(new Server("www.google.com:80"));
+        
+        public MyServerList() {
+        }
+        
+        public MyServerList(IClientConfig clientConfig) {
+        }
+        
+        @Override
+        public List<Server> getInitialListOfServers() {
+            return list;
+        }
+
+        @Override
+        public List<Server> getUpdatedListOfServers() {
+            latch.countDown();
+            return list;
+        }
+
+        @Override
+        public void initWithNiwsConfig(IClientConfig clientConfig) {
+        }
+        
+    }
+
+    @Test
+    public void testDynamicServerListLoadBalancer() {
+        DefaultClientConfigImpl config = DefaultClientConfigImpl.getClientConfigWithDefaultValues();
+        config.setProperty(CommonClientConfigKey.NIWSServerListClassName, MyServerList.class.getName());
+        config.setProperty(CommonClientConfigKey.NFLoadBalancerClassName, DynamicServerListLoadBalancer.class.getName());
+        config.setProperty(CommonClientConfigKey.ServerListRefreshInterval, "50");
+        DynamicServerListLoadBalancer<Server> lb = new DynamicServerListLoadBalancer<Server>(config);
+        try {
+            assertTrue(MyServerList.latch.await(2, TimeUnit.SECONDS));
+        } catch (InterruptedException e) { // NOPMD
+        }
+        assertEquals(lb.getServerList(false), MyServerList.list);
+    }
+}
+