权重随机算法独立成类

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/decorator/ZoneAvoidanceRuleDecorator.java

@@ -10,56 +10,33 @@ package com.nepxion.discovery.plugin.framework.decorator;
  */
 
 import java.util.List;
-import java.util.Map;
-import java.util.concurrent.ThreadLocalRandom;
+
+import javax.annotation.PostConstruct;
 
 import org.apache.commons.collections4.CollectionUtils;
-import org.apache.commons.collections4.MapUtils;
-import org.apache.commons.lang3.StringUtils;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 
-import com.nepxion.discovery.common.entity.DiscoveryEntity;
-import com.nepxion.discovery.common.entity.RuleEntity;
 import com.nepxion.discovery.common.entity.WeightEntity;
-import com.nepxion.discovery.common.entity.WeightFilterEntity;
-import com.nepxion.discovery.common.exception.DiscoveryException;
 import com.nepxion.discovery.plugin.framework.adapter.PluginAdapter;
+import com.nepxion.discovery.plugin.framework.loadbalance.WeightRandomLoadBalance;
 import com.netflix.loadbalancer.Server;
 import com.netflix.loadbalancer.ZoneAvoidanceRule;
 
 public class ZoneAvoidanceRuleDecorator extends ZoneAvoidanceRule {
-    private static final Logger LOG = LoggerFactory.getLogger(ZoneAvoidanceRuleDecorator.class);
-
     @Autowired
     private PluginAdapter pluginAdapter;
 
-    @Override
-    public Server choose(Object key) {
-        RuleEntity ruleEntity = pluginAdapter.getRule();
-        if (ruleEntity == null) {
-            return super.choose(key);
-        }
-
-        DiscoveryEntity discoveryEntity = ruleEntity.getDiscoveryEntity();
-        if (discoveryEntity == null) {
-            return super.choose(key);
-        }
+    private WeightRandomLoadBalance weightRandomLoadBalance;
 
-        WeightFilterEntity weightFilterEntity = discoveryEntity.getWeightFilterEntity();
-        if (weightFilterEntity == null) {
-            return super.choose(key);
-        }
-
-        Map<String, List<WeightEntity>> weightEntityMap = weightFilterEntity.getWeightEntityMap();
-        if (MapUtils.isEmpty(weightEntityMap)) {
-            return super.choose(key);
-        }
-
-        String serviceId = pluginAdapter.getServiceId();
+    @PostConstruct
+    private void initialize() {
+        weightRandomLoadBalance = new WeightRandomLoadBalance();
+        weightRandomLoadBalance.setPluginAdapter(pluginAdapter);
+    }
 
-        List<WeightEntity> weightEntityList = weightEntityMap.get(serviceId);
+    @Override
+    public Server choose(Object key) {
+        List<WeightEntity> weightEntityList = weightRandomLoadBalance.getWeightEntityList();
         if (CollectionUtils.isEmpty(weightEntityList)) {
             return super.choose(key);
         }
@@ -67,78 +44,9 @@ public class ZoneAvoidanceRuleDecorator extends ZoneAvoidanceRule {
         List<Server> eligibleServers = getPredicate().getEligibleServers(getLoadBalancer().getAllServers(), key);
 
         try {
-            return choose(eligibleServers, weightEntityList);
+            return weightRandomLoadBalance.choose(eligibleServers, weightEntityList);
         } catch (Exception e) {
             return super.choose(key);
         }
     }
-
-    private Server choose(List<Server> serverList, List<WeightEntity> weightEntityList) {
-        if (CollectionUtils.isEmpty(serverList)) {
-            return null;
-        }
-
-        int[] weights = new int[serverList.size()];
-        for (int i = 0; i < serverList.size(); i++) {
-            Server server = serverList.get(i);
-            int weight = getWeight(server, weightEntityList);
-            if (weight > 0) {
-                weights[i] = weight;
-            }
-        }
-
-        int index = getIndex(weights);
-
-        return serverList.get(index);
-    }
-
-    private int getIndex(int[] weights) {
-        // 次序号/权重区间值
-        int[][] weightHolder = new int[weights.length][2];
-        // 总权重
-        int totalWeight = 0;
-        // 赋值次序号和区间值累加的数组值，从小到大排列
-        // 例如，对于权重分别为20，40， 60的三个服务，将形成[0, 20)，[20, 60)，[60, 120]三个区间
-        for (int i = 0; i < weights.length; i++) {
-            if (weights[i] <= 0) {
-                continue;
-            }
-
-            totalWeight += weights[i];
-            weightHolder[i][0] = i;
-            weightHolder[i][1] = totalWeight;
-        }
-
-        // 获取介于0(含)和n(不含)伪随机，均匀分布的int值
-        int hitWeight = ThreadLocalRandom.current().nextInt(totalWeight) + 1; // [1, totalWeight)
-        for (int i = 0; i < weightHolder.length; i++) {
-            if (hitWeight <= weightHolder[i][1]) {
-                return weightHolder[i][0];
-            }
-        }
-
-        return weightHolder[0][0];
-    }
-
-    private int getWeight(Server server, List<WeightEntity> weightEntityList) {
-        String providerServiceId = server.getMetaInfo().getAppName();
-        String providerVersion = pluginAdapter.getServerVersion(server);
-
-        for (WeightEntity weightEntity : weightEntityList) {
-            String providerServiceName = weightEntity.getProviderServiceName();
-            if (StringUtils.equalsIgnoreCase(providerServiceName, providerServiceId)) {
-                Map<String, Integer> weightMap = weightEntity.getWeightMap();
-                Integer weight = weightMap.get(providerVersion);
-                if (weight != null) {
-                    return weight;
-                } else {
-                    LOG.error("Weight isn't configed for serviceId={}, version={}", providerServiceId, providerVersion);
-
-                    throw new DiscoveryException("Weight isn't configed for serviceId=" + providerServiceId + ", version=" + providerVersion);
-                }
-            }
-        }
-
-        return -1;
-    }
 }
\ No newline at end of file

discovery-plugin-framework/src/main/java/com/nepxion/discovery/plugin/framework/loadbalance/WeightRandomLoadBalance.java

+package com.nepxion.discovery.plugin.framework.loadbalance;
+
+/**
+ * <p>Title: Nepxion Discovery</p>
+ * <p>Description: Nepxion Discovery</p>
+ * <p>Copyright: Copyright (c) 2017-2050</p>
+ * <p>Company: Nepxion</p>
+ * @author Haojun Ren
+ * @version 1.0
+ */
+
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ThreadLocalRandom;
+
+import org.apache.commons.collections4.CollectionUtils;
+import org.apache.commons.collections4.MapUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.nepxion.discovery.common.entity.DiscoveryEntity;
+import com.nepxion.discovery.common.entity.RuleEntity;
+import com.nepxion.discovery.common.entity.WeightEntity;
+import com.nepxion.discovery.common.entity.WeightFilterEntity;
+import com.nepxion.discovery.common.exception.DiscoveryException;
+import com.nepxion.discovery.plugin.framework.adapter.PluginAdapter;
+import com.netflix.loadbalancer.Server;
+
+public class WeightRandomLoadBalance {
+    private static final Logger LOG = LoggerFactory.getLogger(WeightRandomLoadBalance.class);
+
+    private PluginAdapter pluginAdapter;
+
+    public List<WeightEntity> getWeightEntityList() {
+        RuleEntity ruleEntity = pluginAdapter.getRule();
+        if (ruleEntity == null) {
+            return null;
+        }
+
+        DiscoveryEntity discoveryEntity = ruleEntity.getDiscoveryEntity();
+        if (discoveryEntity == null) {
+            return null;
+        }
+
+        WeightFilterEntity weightFilterEntity = discoveryEntity.getWeightFilterEntity();
+        if (weightFilterEntity == null) {
+            return null;
+        }
+
+        Map<String, List<WeightEntity>> weightEntityMap = weightFilterEntity.getWeightEntityMap();
+        if (MapUtils.isEmpty(weightEntityMap)) {
+            return null;
+        }
+
+        String serviceId = pluginAdapter.getServiceId();
+
+        List<WeightEntity> weightEntityList = weightEntityMap.get(serviceId);
+
+        return weightEntityList;
+    }
+
+    public Server choose(List<Server> serverList, List<WeightEntity> weightEntityList) {
+        if (CollectionUtils.isEmpty(serverList)) {
+            return null;
+        }
+
+        int[] weights = new int[serverList.size()];
+        for (int i = 0; i < serverList.size(); i++) {
+            Server server = serverList.get(i);
+            int weight = getWeight(server, weightEntityList);
+            if (weight > 0) {
+                weights[i] = weight;
+            }
+        }
+
+        int index = getIndex(weights);
+
+        return serverList.get(index);
+    }
+
+    private int getIndex(int[] weights) {
+        // 次序号/权重区间值
+        int[][] weightHolder = new int[weights.length][2];
+        // 总权重
+        int totalWeight = 0;
+        // 赋值次序号和区间值累加的数组值，从小到大排列
+        // 例如，对于权重分别为20，40， 60的三个服务，将形成[0, 20)，[20, 60)，[60, 120]三个区间
+        for (int i = 0; i < weights.length; i++) {
+            if (weights[i] <= 0) {
+                continue;
+            }
+
+            totalWeight += weights[i];
+            weightHolder[i][0] = i;
+            weightHolder[i][1] = totalWeight;
+        }
+
+        // 获取介于0(含)和n(不含)伪随机，均匀分布的int值
+        int hitWeight = ThreadLocalRandom.current().nextInt(totalWeight) + 1; // [1, totalWeight)
+        for (int i = 0; i < weightHolder.length; i++) {
+            if (hitWeight <= weightHolder[i][1]) {
+                return weightHolder[i][0];
+            }
+        }
+
+        return weightHolder[0][0];
+    }
+
+    private int getWeight(Server server, List<WeightEntity> weightEntityList) {
+        String providerServiceId = server.getMetaInfo().getAppName();
+        String providerVersion = pluginAdapter.getServerVersion(server);
+
+        for (WeightEntity weightEntity : weightEntityList) {
+            String providerServiceName = weightEntity.getProviderServiceName();
+            if (StringUtils.equalsIgnoreCase(providerServiceName, providerServiceId)) {
+                Map<String, Integer> weightMap = weightEntity.getWeightMap();
+                Integer weight = weightMap.get(providerVersion);
+                if (weight != null) {
+                    return weight;
+                } else {
+                    LOG.error("Weight isn't configed for serviceId={}, version={}", providerServiceId, providerVersion);
+
+                    throw new DiscoveryException("Weight isn't configed for serviceId=" + providerServiceId + ", version=" + providerVersion);
+                }
+            }
+        }
+
+        return -1;
+    }
+
+    public void setPluginAdapter(PluginAdapter pluginAdapter) {
+        this.pluginAdapter = pluginAdapter;
+    }
+}
\ No newline at end of file