Miscellaneous update

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

sentinel-core/src/main/java/com/alibaba/csp/sentinel/CtSph.java

@@ -88,8 +88,8 @@ public class CtSph implements Sph {
         ProcessorSlot<Object> chain = lookProcessChain(resourceWrapper);
 
         /*
-         * Means processor size exceeds {@link Constants.MAX_ENTRY_SIZE}, no
-         * rule checking will do.
+         * Means processor cache size exceeds {@link Constants.MAX_SLOT_CHAIN_SIZE}, so no
+         * rule checking will be done.
          */
         if (chain == null) {
             return new CtEntry(resourceWrapper, null, context);
@@ -102,7 +102,7 @@ public class CtSph implements Sph {
             e.exit(count, args);
             throw e1;
         } catch (Throwable e1) {
-            RecordLog.info("sentinel unexpected exception", e1);
+            RecordLog.info("Sentinel unexpected exception", e1);
         }
         return e;
     }
@@ -134,8 +134,7 @@ public class CtSph implements Sph {
                     }
 
                     chain = Env.slotsChainbuilder.build();
-                    HashMap<ResourceWrapper, ProcessorSlotChain> newMap
-                        = new HashMap<ResourceWrapper, ProcessorSlotChain>(
+                    Map<ResourceWrapper, ProcessorSlotChain> newMap = new HashMap<ResourceWrapper, ProcessorSlotChain>(
                         chainMap.size() + 1);
                     newMap.putAll(chainMap);
                     newMap.put(resourceWrapper, chain);

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/FlowRule.java

@@ -53,13 +53,23 @@ public class FlowRule extends AbstractRule {
      */
     private int grade = RuleConstant.FLOW_GRADE_QPS;
 
+    /**
+     * Flow control threshold count.
+     */
     private double count;
 
     /**
-     * 0为直接限流;1为关联限流;2为链路限流
+     * Flow control strategy based on invocation chain.
+     *
+     * {@link RuleConstant#STRATEGY_DIRECT} for direct flow control (by origin);
+     * {@link RuleConstant#STRATEGY_RELATE} for relevant flow control (with relevant resource);
+     * {@link RuleConstant#STRATEGY_CHAIN} for chain flow control (by entrance resource).
      */
     private int strategy = RuleConstant.STRATEGY_DIRECT;
 
+    /**
+     * Reference resource in flow control with relevant resource.
+     */
     private String refResource;
 
     /**

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/block/flow/FlowRuleManager.java

@@ -86,9 +86,6 @@ public class FlowRuleManager {
      */
     public static List<FlowRule> getRules() {
         List<FlowRule> rules = new ArrayList<FlowRule>();
-        if (flowRules == null) {
-            return rules;
-        }
         for (Map.Entry<String, List<FlowRule>> entry : flowRules.entrySet()) {
             rules.addAll(entry.getValue());
         }
@@ -145,13 +142,11 @@ public class FlowRuleManager {
 
     public static void checkFlow(ResourceWrapper resource, Context context, DefaultNode node, int count)
         throws BlockException {
-        if (flowRules != null) {
-            List<FlowRule> rules = flowRules.get(resource.getName());
-            if (rules != null) {
-                for (FlowRule rule : rules) {
-                    if (!rule.passCheck(context, node, count)) {
-                        throw new FlowException(rule.getLimitApp());
-                    }
+        List<FlowRule> rules = flowRules.get(resource.getName());
+        if (rules != null) {
+            for (FlowRule rule : rules) {
+                if (!rule.passCheck(context, node, count)) {
+                    throw new FlowException(rule.getLimitApp());
                 }
             }
         }
@@ -166,14 +161,12 @@ public class FlowRuleManager {
             return false;
         }
 
-        if (flowRules != null) {
-            List<FlowRule> rules = flowRules.get(resourceName);
+        List<FlowRule> rules = flowRules.get(resourceName);
 
-            if (rules != null) {
-                for (FlowRule rule : rules) {
-                    if (origin.equals(rule.getLimitApp())) {
-                        return false;
-                    }
+        if (rules != null) {
+            for (FlowRule rule : rules) {
+                if (origin.equals(rule.getLimitApp())) {
+                    return false;
                 }
             }
         }
@@ -190,7 +183,7 @@ public class FlowRuleManager {
                 flowRules.clear();
                 flowRules.putAll(rules);
             }
-            RecordLog.info("receive flow config: " + flowRules);
+            RecordLog.info("[FlowRuleManager] Flow rules received: " + flowRules);
         }
 
         @Override
@@ -200,7 +193,7 @@ public class FlowRuleManager {
                 flowRules.clear();
                 flowRules.putAll(rules);
             }
-            RecordLog.info("load flow config: " + flowRules);
+            RecordLog.info("[FlowRuleManager] Flow rules loaded: " + flowRules);
         }
 
     }

sentinel-core/src/main/java/com/alibaba/csp/sentinel/slots/nodeselector/NodeSelectorSlot.java

@@ -128,7 +128,7 @@ public class NodeSelectorSlot extends AbstractLinkedProcessorSlot<Object> {
     /**
      * {@link DefaultNode}s of the same resource in different context.
      */
-    private Map<String, DefaultNode> map = new HashMap<String, DefaultNode>(10);
+    private volatile Map<String, DefaultNode> map = new HashMap<String, DefaultNode>(10);
 
     @Override
     public void entry(Context context, ResourceWrapper resourceWrapper, Object obj, int count, Object... args)

sentinel-demo/sentinel-demo-basic/pom.xml

@@ -10,8 +10,4 @@
     </parent>
     <artifactId>sentinel-demo-basic</artifactId>
 
-    <dependencies>
-        
-    </dependencies>
-
 </project>

sentinel-demo/sentinel-demo-basic/src/main/java/com/alibaba/csp/sentinel/demo/flow/FlowQpsDemo.java

@@ -42,18 +42,19 @@ public class FlowQpsDemo {
 
     private static volatile boolean stop = false;
 
-    private static final int threadCount = 1;
+    private static final int threadCount = 32;
 
     private static int seconds = 60 + 40;
 
     public static void main(String[] args) throws Exception {
+        initFlowQpsRule();
+
         tick();
         // first make the system run on a very low condition
         simulateTraffic();
 
         System.out.println("===== begin to do flow control");
         System.out.println("only 20 requests per second can pass");
-        initFlowQpsRule();
 
     }