TpsLimitFilter

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/support/wrapper/MockClusterInvoker.java

@@ -94,7 +94,7 @@ public class MockClusterInvoker<T> implements Invoker<T> {
 
     @SuppressWarnings({"unchecked", "rawtypes"})
     private Result doMockInvoke(Invocation invocation, RpcException e) {
-        Result result = null;
+        Result result;
         Invoker<T> minvoker;
 
         List<Invoker<T>> mockInvokers = selectMockInvoker(invocation);

dubbo-common/src/main/java/com/alibaba/dubbo/common/Constants.java

@@ -608,10 +608,19 @@ public class Constants {
 
     public static final String RELIABLE_PROTOCOL = "napoli";
 
+    /**
+     * TPS 限制 - 大小配置项
+     *
+     * TpsLimitFilter
+     */
     public static final String TPS_LIMIT_RATE_KEY = "tps";
-
+    /**
+     * TPS 限制 - 周期配置项
+     */
     public static final String TPS_LIMIT_INTERVAL_KEY = "tps.interval";
-
+    /**
+     * TPS 限制 - 周期默认值
+     */
     public static final long DEFAULT_TPS_LIMIT_INTERVAL = 60 * 1000;
 
     public static final String DECODE_IN_IO_THREAD_KEY = "decode.in.io";

dubbo-common/src/main/java/com/alibaba/dubbo/common/utils/ReflectUtils.java

@@ -209,17 +209,21 @@ public final class ReflectUtils {
     }
 
     public static String getCodeBase(Class<?> cls) {
-        if (cls == null)
+        if (cls == null) {
             return null;
+        }
         ProtectionDomain domain = cls.getProtectionDomain();
-        if (domain == null)
+        if (domain == null) {
             return null;
+        }
         CodeSource source = domain.getCodeSource();
-        if (source == null)
+        if (source == null) {
             return null;
+        }
         URL location = source.getLocation();
-        if (location == null)
+        if (location == null) {
             return null;
+        }
         return location.getFile();
     }
 

dubbo-config/dubbo-config-api/src/main/java/com/alibaba/dubbo/config/AbstractInterfaceConfig.java

@@ -354,6 +354,7 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
      * @param interfaceClass 接口类
      */
     protected void checkStubAndMock(Class<?> interfaceClass) {
+        // `local` 配置项的校验，和 `stub` 一样。
         if (ConfigUtils.isNotEmpty(local)) {
             Class<?> localClass = ConfigUtils.isDefault(local) ? ReflectUtils.forName(interfaceClass.getName() + "Local") : ReflectUtils.forName(local);
             if (!interfaceClass.isAssignableFrom(localClass)) {
@@ -365,11 +366,15 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
                 throw new IllegalStateException("No such constructor \"public " + localClass.getSimpleName() + "(" + interfaceClass.getName() + ")\" in local implementation class " + localClass.getName());
             }
         }
+        // `stub` 配置项的校验
         if (ConfigUtils.isNotEmpty(stub)) {
+            // `stub = true` 的情况，使用接口 + `Stub` 字符串。
             Class<?> localClass = ConfigUtils.isDefault(stub) ? ReflectUtils.forName(interfaceClass.getName() + "Stub") : ReflectUtils.forName(stub);
+            // Stub 类，必须实现服务接口
             if (!interfaceClass.isAssignableFrom(localClass)) {
                 throw new IllegalStateException("The local implementation class " + localClass.getName() + " not implement interface " + interfaceClass.getName());
             }
+            // Stub 类，必须带有服务接口的构造方法
             try {
                 ReflectUtils.findConstructor(localClass, interfaceClass);
             } catch (NoSuchMethodException e) {

dubbo-config/dubbo-config-api/src/main/java/com/alibaba/dubbo/config/ReferenceConfig.java

@@ -362,7 +362,7 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
                 map.put("revision", revision);
             }
 
-            String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames(); // 【TODO 8003】Wrapper
+            String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames(); // 获得方法数组
             if (methods.length == 0) {
                 logger.warn("NO method found in service interface " + interfaceClass.getName());
                 map.put("methods", Constants.ANY_VALUE);

dubbo-config/dubbo-config-api/src/main/java/com/alibaba/dubbo/config/ServiceConfig.java

@@ -411,7 +411,7 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
         if (path == null || path.length() == 0) {
             path = interfaceName;
         }
-        // 暴露
+        // 暴露服务
         doExportUrls();
         // TODO 芋艿，等待 qos
         ProviderModel providerModel = new ProviderModel(getUniqueServiceName(), this, ref);
@@ -568,7 +568,7 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
                 map.put("revision", revision); // 修订本
             }
 
-            String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames(); // 【TODO 8003】Wrapper
+            String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames(); // 获得方法数组
             if (methods.length == 0) {
                 logger.warn("NO method found in service interface " + interfaceClass.getName());
                 map.put("methods", Constants.ANY_VALUE);
@@ -578,7 +578,7 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
         }
         // token ，参见《令牌校验》https://dubbo.gitbooks.io/dubbo-user-book/demos/token-authorization.html
         if (!ConfigUtils.isEmpty(token)) {
-            if (ConfigUtils.isDefault(token)) {
+            if (ConfigUtils.isDefault(token)) { // true || default 时，UUID 随机生成
                 map.put("token", UUID.randomUUID().toString());
             } else {
                 map.put("token", token);

dubbo-demo/dubbo-demo-api/src/main/java/com/alibaba/dubbo/demo/TestException.java

+package com.alibaba.dubbo.demo;
+
+public class TestException extends RuntimeException {
+}

dubbo-demo/dubbo-demo-consumer/src/main/java/com/alibaba/dubbo/demo/consumer/Consumer.java

@@ -41,11 +41,11 @@ public class Consumer {
 //                System.out.println(hello); // get result
 
 
-                demoService.say01(null);
-                demoService.say01("hahha");
-                demoService.say02();
-                demoService.say03();
-                demoService.say04();
+//                demoService.say01(null);
+                demoService.say01("TestException");
+//                demoService.say02();
+//                demoService.say03();
+//                demoService.say04();
 
                 // 参数回调
                 // https://dubbo.gitbooks.io/dubbo-user-book/demos/callback-parameter.html

dubbo-demo/dubbo-demo-consumer/src/main/java/com/alibaba/dubbo/demo/consumer/DemoServiceStub.java

+package com.alibaba.dubbo.demo.consumer;
+
+import com.alibaba.dubbo.demo.DemoService;
+import com.alibaba.dubbo.demo.ParamCallback;
+
+public class DemoServiceStub implements DemoService {
+
+    private DemoService demoService;
+
+    public DemoServiceStub(DemoService demoService) {
+        this.demoService = demoService;
+    }
+
+    @Override
+    public String sayHello(String name) {
+        return null;
+    }
+
+    @Override
+    public void bye(Object o) {
+        System.out.println("o");
+    }
+
+    @Override
+    public void callbackParam(String msg, ParamCallback callback) {
+        System.out.println("o");
+    }
+
+    @Override
+    public String say01(String msg) {
+        return null;
+    }
+
+    @Override
+    public String[] say02() {
+        return new String[0];
+    }
+
+    @Override
+    public void say03() {
+        System.out.println("o");
+    }
+
+    @Override
+    public Void say04() {
+        return null;
+    }
+
+}

dubbo-demo/dubbo-demo-consumer/src/main/resources/META-INF/spring/dubbo-demo-consumer.xml

@@ -29,12 +29,12 @@ limitations under the License.
 
     <!-- use multicast registry center to discover service -->
     <!--<dubbo:registry address="multicast://224.5.6.7:1234"/>-->
-    <!--<dubbo:registry address="zookeeper://127.0.0.1:2181"/>-->
-    <dubbo:registry address="redis://127.0.0.1:6379"/>
+    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>
+    <!--<dubbo:registry address="redis://127.0.0.1:6379"/>-->
 
     <!-- generate proxy for the remote service, then demoService can be used in the same way as the
     local regular interface -->
-    <dubbo:reference id="demoService" check="false" interface="com.alibaba.dubbo.demo.DemoService" client="netty4" timeout="100000" callbacks="1000">
+    <dubbo:reference id="demoService" check="false" interface="com.alibaba.dubbo.demo.DemoService" client="netty4" timeout="100000" callbacks="1000" >
         <!--<dubbo:method name="sayHello" />-->
 
         <!--url="registry://127.0.0.1:2181?registry=zookeeper;127.0.0.1:2181;127.0.0.1:27018"-->
@@ -45,5 +45,6 @@ limitations under the License.
         
     </dubbo:reference>
 
+    <!--stub="com.alibaba.dubbo.demo.consumer.DemoServiceStub"-->
 
 </beans>
\ No newline at end of file

dubbo-demo/dubbo-demo-injvm/src/main/java/com/alibaba/dubbo/demo/consumer/DemoServiceImpl.java

@@ -17,6 +17,8 @@
 package com.alibaba.dubbo.demo.consumer;
 
 import com.alibaba.dubbo.demo.DemoService;
+import com.alibaba.dubbo.demo.ParamCallback;
+import com.alibaba.dubbo.demo.TestException;
 import com.alibaba.dubbo.rpc.RpcContext;
 import com.alibaba.fastjson.JSON;
 
@@ -36,6 +38,37 @@ public class DemoServiceImpl implements DemoService {
         System.out.println(o.getClass());
     }
 
+    @Override
+    public void callbackParam(String msg, ParamCallback callback) {
+
+    }
+
+    @Override
+    public String say01(String msg) {
+        if ("RuntimeException".equalsIgnoreCase(msg)) {
+            throw new RuntimeException("123");
+        }
+        if ("TestException".equalsIgnoreCase(msg)) {
+            throw new TestException();
+        }
+        return null;
+    }
+
+    @Override
+    public String[] say02() {
+        return new String[0];
+    }
+
+    @Override
+    public void say03() {
+
+    }
+
+    @Override
+    public Void say04() {
+        return null;
+    }
+
 //    public String getTest01() {
 //        return test01;
 //    }

dubbo-demo/dubbo-demo-injvm/src/main/java/com/alibaba/dubbo/demo/consumer/InjvmConsumer.java

@@ -32,7 +32,7 @@ public class InjvmConsumer {
         while (true) {
             try {
                 Thread.sleep(1000);
-                String hello = demoService.sayHello("world"); // call remote method
+                String hello = demoService.say01("RuntimeException"); // call remote method
                 System.out.println(hello); // get result
 
 //                demoService.bye(new Cat().setName("小猫"));

dubbo-demo/dubbo-demo-injvm/src/main/resources/META-INF/dubbo/com.alibaba.dubbo.rpc.Filter

+tps=com.alibaba.dubbo.rpc.filter.TpsLimitFilter
\ No newline at end of file

dubbo-demo/dubbo-demo-injvm/src/main/resources/META-INF/spring/dubbo-demo-injvm.xml

@@ -30,6 +30,13 @@ limitations under the License.
     </dubbo:reference>
 
     <bean id="demoServiceImpl" class="com.alibaba.dubbo.demo.consumer.DemoServiceImpl"/>
-    <dubbo:service interface="com.alibaba.dubbo.demo.DemoService" ref="demoServiceImpl" protocol="injvm"  />
+
+    <dubbo:service interface="com.alibaba.dubbo.demo.DemoService" ref="demoServiceImpl" protocol="injvm" >
+        <dubbo:parameter key="tps" value="100" />
+    </dubbo:service>
+
+    <dubbo:provider>
+
+    </dubbo:provider>
 
 </beans>
\ No newline at end of file

dubbo-demo/dubbo-demo-provider/src/main/java/com/alibaba/dubbo/demo/provider/DemoServiceStub.java

+package com.alibaba.dubbo.demo.provider;
+
+import com.alibaba.dubbo.demo.DemoService;
+import com.alibaba.dubbo.demo.ParamCallback;
+
+public class DemoServiceStub implements DemoService {
+
+    private DemoService demoService;
+
+    public DemoServiceStub(DemoService demoService) {
+        this.demoService = demoService;
+    }
+
+    @Override
+    public String sayHello(String name) {
+        return null;
+    }
+
+    @Override
+    public void bye(Object o) {
+        System.out.println("o");
+    }
+
+    @Override
+    public void callbackParam(String msg, ParamCallback callback) {
+        System.out.println("o");
+    }
+
+    @Override
+    public String say01(String msg) {
+        return null;
+    }
+
+    @Override
+    public String[] say02() {
+        return new String[0];
+    }
+
+    @Override
+    public void say03() {
+        System.out.println("o");
+    }
+
+    @Override
+    public Void say04() {
+        return null;
+    }
+
+}

dubbo-demo/dubbo-demo-provider/src/main/resources/META-INF/spring/dubbo-demo-provider.xml

@@ -32,8 +32,8 @@ limitations under the License.
     <!--<dubbo:registry address="multicast://224.5.6.7:1234"/>-->
     <!--<dubbo:registry address="zookeeper://127.0.0.1:2181"/>-->
     <!--<dubbo:registry address="zookeeper://127.0.0.1:2181||10.20.153.11:2181,10.20.153.12:2181"/>-->
-    <!--<dubbo:registry address="zookeeper://127.0.0.1:2181" />-->
-    <dubbo:registry address="redis://127.0.0.1:6379" />
+    <dubbo:registry address="zookeeper://127.0.0.1:2181" />
+    <!--<dubbo:registry address="redis://127.0.0.1:6379" />-->
 
 
     <bean id="demoDAO" class="com.alibaba.dubbo.demo.provider.DemoDAO" />
@@ -41,10 +41,10 @@ limitations under the License.
     <!-- service implementation, as same as regular local bean -->
     <bean id="demoService" class="com.alibaba.dubbo.demo.provider.DemoServiceImpl"/>
 
-    <bean id="genericService" class="com.alibaba.dubbo.demo.provider.MyGenericService" />
+    <!--<bean id="genericService" class="com.alibaba.dubbo.demo.provider.MyGenericService" />-->
 
     <!-- declare the service interface to be exported -->
-    <dubbo:service interface="com.alibaba.dubbo.demo.DemoService" ref="demoService" filter="demo" deprecated="true" callbacks="1000" timeout="200000">
+    <dubbo:service interface="com.alibaba.dubbo.demo.DemoService" ref="demoService" filter="demo" deprecated="false" callbacks="1000" timeout="200000" accesslog="true">
     <!--<dubbo:service interface="com.alibaba.dubbo.demo.DemoService" protocol="dubbo" ref="demoService"/>-->
     <!--<dubbo:service id="sa" interface="com.alibaba.dubbo.demo.DemoService" protocol="dubbo" class="com.alibaba.dubbo.demo.provider.DemoServiceImpl">-->
         <!--&lt;!&ndash;<dubbo:method name="sayHello" retries="100">&ndash;&gt;-->
@@ -60,20 +60,22 @@ limitations under the License.
         <!--&lt;!&ndash;<dubbo:argument type="com.demo.CallbackListener" callback="true" />&ndash;&gt;-->
         <!--&lt;!&ndash;</dubbo:method>&ndash;&gt;-->
 
-        <dubbo:parameter key="threadname" value="shuaiqi" />
-        <dubbo:parameter key="threads" value="123" />
-        <dubbo:parameter key="queues" value="10" />
+        <!--<dubbo:parameter key="threadname" value="shuaiqi" />-->
+        <!--<dubbo:parameter key="threads" value="123" />-->
+        <!--<dubbo:parameter key="queues" value="10" />-->
+
+        <!--<dubbo:method name="callbackParam">-->
+            <!--<dubbo:argument callback="true" type="com.alibaba.dubbo.demo.ParamCallback" />-->
+        <!--</dubbo:method>-->
+        <dubbo:method name="say01" deprecated="true" />
 
-        <dubbo:method name="callbackParam">
-            <dubbo:argument callback="true" type="com.alibaba.dubbo.demo.ParamCallback" />
-        </dubbo:method>
 
     </dubbo:service>
 
-    <dubbo:service interface="com.alibaba.dubbo.demo.BarService" ref="genericService" timeout="200000" />
+    <!--<dubbo:service interface="com.alibaba.dubbo.demo.BarService" ref="genericService" timeout="200000" />-->
 
     <!-- use dubbo protocol to export service on port 20880 -->
-    <dubbo:protocol name="dubbo" port="20880" server="netty4" />
+    <dubbo:protocol accesslog="true" name="dubbo" port="20880" server="netty4" />
     <!--<dubbo:protocol id="pb" name="dubbo" port="20881"/>-->
 
 </beans>
\ No newline at end of file

dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/status/RegistryStatusChecker.java

@@ -33,7 +33,7 @@ public class RegistryStatusChecker implements StatusChecker {
 
     public Status check() {
         Collection<Registry> regsitries = AbstractRegistryFactory.getRegistries();
-        if (regsitries == null || regsitries.isEmpty()) {
+        if (regsitries.isEmpty()) {
             return new Status(Status.Level.UNKNOWN);
         }
         Status.Level level = Status.Level.OK;

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/RpcException.java

@@ -26,13 +26,14 @@ package com.alibaba.dubbo.rpc;
  */
 public final class RpcException extends RuntimeException {
 
+    private static final long serialVersionUID = 7815426752583648734L;
+
     public static final int UNKNOWN_EXCEPTION = 0;
     public static final int NETWORK_EXCEPTION = 1;
     public static final int TIMEOUT_EXCEPTION = 2;
     public static final int BIZ_EXCEPTION = 3;
     public static final int FORBIDDEN_EXCEPTION = 4;
     public static final int SERIALIZATION_EXCEPTION = 5;
-    private static final long serialVersionUID = 7815426752583648734L;
     private int code; // RpcException cannot be extended, use error code for exception type to keep compatibility
 
     public RpcException() {

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/RpcStatus.java

@@ -28,41 +28,91 @@ import java.util.concurrent.atomic.AtomicLong;
 /**
  * URL statistics. (API, Cached, ThreadSafe)
  *
+ * RPC 状态。可以计入如下维度统计：
+ *
+ * 1. 基于服务 URL ，{@link #SERVICE_STATISTICS}
+ * 2. 基于服务 URL + 方法，{@link #METHOD_STATISTICS}
+ *
  * @see com.alibaba.dubbo.rpc.filter.ActiveLimitFilter
  * @see com.alibaba.dubbo.rpc.filter.ExecuteLimitFilter
- * @see com.alibaba.dubbo.rpc.cluster.loadbalance.LeastActiveLoadBalance
+ * @see .com.alibaba.dubbo.rpc.cluster.loadbalance.LeastActiveLoadBalance
  */
 public class RpcStatus {
 
+    /**
+     * 基于服务 URL 为维度的 RpcStatus 集合
+     *
+     * key：URL
+     */
     private static final ConcurrentMap<String, RpcStatus> SERVICE_STATISTICS = new ConcurrentHashMap<String, RpcStatus>();
-
+    /**
+     * 基于服务 URL + 方法维度的 RpcStatus 集合
+     *
+     * key1：URL
+     * key2：方法名
+     */
     private static final ConcurrentMap<String, ConcurrentMap<String, RpcStatus>> METHOD_STATISTICS = new ConcurrentHashMap<String, ConcurrentMap<String, RpcStatus>>();
+
+    // 目前没有用到
     private final ConcurrentMap<String, Object> values = new ConcurrentHashMap<String, Object>();
+    /**
+     * 调用中的次数
+     */
     private final AtomicInteger active = new AtomicInteger();
+    /**
+     * 总调用次数
+     */
     private final AtomicLong total = new AtomicLong();
+    /**
+     * 总调用失败次数
+     */
     private final AtomicInteger failed = new AtomicInteger();
+    /**
+     * 总调用时长，单位：毫秒
+     */
     private final AtomicLong totalElapsed = new AtomicLong();
+    /**
+     * 总调用失败时长，单位：毫秒
+     */
     private final AtomicLong failedElapsed = new AtomicLong();
+    /**
+     * 最大调用时长，单位：毫秒
+     */
     private final AtomicLong maxElapsed = new AtomicLong();
+    /**
+     * 最大调用失败时长，单位：毫秒
+     */
     private final AtomicLong failedMaxElapsed = new AtomicLong();
+    /**
+     * 最大调用成功时长，单位：毫秒
+     */
     private final AtomicLong succeededMaxElapsed = new AtomicLong();
 
     /**
      * Semaphore used to control concurrency limit set by `executes`
+     *
+     * 服务执行信号量，在 {@link com.alibaba.dubbo.rpc.filter.ExecuteLimitFilter} 中使用
      */
     private volatile Semaphore executesLimit;
+    /**
+     * 服务执行信号量大小
+     */
     private volatile int executesPermits;
 
     private RpcStatus() {
     }
 
     /**
-     * @param url
+     * 获得 RpcStatus 对象
+     *
+     * @param url URL
      * @return status
      */
     public static RpcStatus getStatus(URL url) {
         String uri = url.toIdentityString();
+        // 获得
         RpcStatus status = SERVICE_STATISTICS.get(uri);
+        // 不存在，则进行创建
         if (status == null) {
             SERVICE_STATISTICS.putIfAbsent(uri, new RpcStatus());
             status = SERVICE_STATISTICS.get(uri);
@@ -79,18 +129,25 @@ public class RpcStatus {
     }
 
     /**
-     * @param url
-     * @param methodName
+     * 获得 RpcStatus 对象
+     *
+     * @param url URL
+     * @param methodName 方法
      * @return status
      */
     public static RpcStatus getStatus(URL url, String methodName) {
         String uri = url.toIdentityString();
+        // 获得方法集合
         ConcurrentMap<String, RpcStatus> map = METHOD_STATISTICS.get(uri);
+        // 不存在，创建方法集合
         if (map == null) {
             METHOD_STATISTICS.putIfAbsent(uri, new ConcurrentHashMap<String, RpcStatus>());
             map = METHOD_STATISTICS.get(uri);
         }
+
+        // 获得 RpcStatus 对象
         RpcStatus status = map.get(methodName);
+        // 不存在，创建 RpcStatus 对象
         if (status == null) {
             map.putIfAbsent(methodName, new RpcStatus());
             status = map.get(methodName);
@@ -110,31 +167,43 @@ public class RpcStatus {
     }
 
     /**
-     * @param url
+     * 服务调用开始的计数
+     *
+     * @param url URL 对象
+     * @param methodName 方法名
      */
     public static void beginCount(URL url, String methodName) {
+        // `SERVICE_STATISTICS` 的计数
         beginCount(getStatus(url));
+        // `METHOD_STATISTICS` 的计数
         beginCount(getStatus(url, methodName));
     }
 
     private static void beginCount(RpcStatus status) {
+        // 调用中的次数
         status.active.incrementAndGet();
     }
 
     /**
-     * @param url
-     * @param elapsed
-     * @param succeeded
+     * 服务调用结束的计数
+     *
+     * @param url URL 对象
+     * @param elapsed 时长，毫秒
+     * @param succeeded 是否成功
      */
     public static void endCount(URL url, String methodName, long elapsed, boolean succeeded) {
+        // `SERVICE_STATISTICS` 的计数
         endCount(getStatus(url), elapsed, succeeded);
+        // `METHOD_STATISTICS` 的计数
         endCount(getStatus(url, methodName), elapsed, succeeded);
     }
 
     private static void endCount(RpcStatus status, long elapsed, boolean succeeded) {
+        // 次数计数
         status.active.decrementAndGet();
         status.total.incrementAndGet();
         status.totalElapsed.addAndGet(elapsed);
+        // 时长计数
         if (status.maxElapsed.get() < elapsed) {
             status.maxElapsed.set(elapsed);
         }
@@ -143,7 +212,7 @@ public class RpcStatus {
                 status.succeededMaxElapsed.set(elapsed);
             }
         } else {
-            status.failed.incrementAndGet();
+            status.failed.incrementAndGet(); // 失败次数
             status.failedElapsed.addAndGet(elapsed);
             if (status.failedMaxElapsed.get() < elapsed) {
                 status.failedMaxElapsed.set(elapsed);
@@ -322,7 +391,7 @@ public class RpcStatus {
         if(maxThreadNum <= 0) {
             return null;
         }
-
+        // 若信号量不存在，或者信号量大小改变，创建新的信号量
         if (executesLimit == null || executesPermits != maxThreadNum) {
             synchronized (this) {
                 if (executesLimit == null || executesPermits != maxThreadNum) {
@@ -331,7 +400,8 @@ public class RpcStatus {
                 }
             }
         }
-
+        // 返回信号量
         return executesLimit;
     }
+
 }
\ No newline at end of file

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/filter/TokenFilter.java

@@ -31,21 +31,26 @@ import java.util.Map;
 /**
  * TokenInvokerFilter
  *
+ * 令牌验证 Filter
  */
 @Activate(group = Constants.PROVIDER, value = Constants.TOKEN_KEY)
 public class TokenFilter implements Filter {
 
-    public Result invoke(Invoker<?> invoker, Invocation inv)
-            throws RpcException {
+    @Override
+    public Result invoke(Invoker<?> invoker, Invocation inv) throws RpcException {
+        // 获得服务提供者配置的 Token 值
         String token = invoker.getUrl().getParameter(Constants.TOKEN_KEY);
         if (ConfigUtils.isNotEmpty(token)) {
+            // 从隐式参数中，获得 Token 值。
             Class<?> serviceType = invoker.getInterface();
             Map<String, String> attachments = inv.getAttachments();
             String remoteToken = attachments == null ? null : attachments.get(Constants.TOKEN_KEY);
+            // 对比，若不一致，抛出 RpcException 异常
             if (!token.equals(remoteToken)) {
                 throw new RpcException("Invalid token! Forbid invoke remote service " + serviceType + " method " + inv.getMethodName() + "() from consumer " + RpcContext.getContext().getRemoteHost() + " to provider " + RpcContext.getContext().getLocalHost());
             }
         }
+        // 服务调用
         return invoker.invoke(inv);
     }
 

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/filter/TpsLimitFilter.java

@@ -30,14 +30,15 @@ import com.alibaba.dubbo.rpc.filter.tps.TPSLimiter;
 /**
  * Limit TPS for either service or service's particular method
  *
+ * TPS 限流过滤器实现类
  */
 @Activate(group = Constants.PROVIDER, value = Constants.TPS_LIMIT_RATE_KEY)
 public class TpsLimitFilter implements Filter {
 
     private final TPSLimiter tpsLimiter = new DefaultTPSLimiter();
 
+    @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
-
         if (!tpsLimiter.isAllowable(invoker.getUrl(), invocation)) {
             throw new RpcException(
                     new StringBuilder(64)
@@ -48,8 +49,8 @@ public class TpsLimitFilter implements Filter {
                             .append(" because exceed max service tps.")
                             .toString());
         }
-
+        // 服务调用
         return invoker.invoke(invocation);
     }
 
-}
+}
\ No newline at end of file

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/filter/tps/DefaultTPSLimiter.java

@@ -23,32 +23,46 @@ import com.alibaba.dubbo.rpc.Invocation;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 
+/**
+ * 默认 TPS 限制器实现类
+ */
 public class DefaultTPSLimiter implements TPSLimiter {
 
-    private final ConcurrentMap<String, StatItem> stats
-            = new ConcurrentHashMap<String, StatItem>();
+    /**
+     * StatItem 集合
+     *
+     * key：服务名
+     */
+    private final ConcurrentMap<String, StatItem> stats = new ConcurrentHashMap<String, StatItem>();
 
+    @Override
     public boolean isAllowable(URL url, Invocation invocation) {
+        // 获得 TPS 大小配置项
         int rate = url.getParameter(Constants.TPS_LIMIT_RATE_KEY, -1);
-        long interval = url.getParameter(Constants.TPS_LIMIT_INTERVAL_KEY,
-                Constants.DEFAULT_TPS_LIMIT_INTERVAL);
+        // 获得 TPS 周期配置项，默认 60 秒
+        long interval = url.getParameter(Constants.TPS_LIMIT_INTERVAL_KEY, Constants.DEFAULT_TPS_LIMIT_INTERVAL);
         String serviceKey = url.getServiceKey();
+        // 要限流
         if (rate > 0) {
+            // 获得 StatItem 对象
             StatItem statItem = stats.get(serviceKey);
+            // 不存在，则进行创建
             if (statItem == null) {
-                stats.putIfAbsent(serviceKey,
-                        new StatItem(serviceKey, rate, interval));
+                stats.putIfAbsent(serviceKey, new StatItem(serviceKey, rate, interval));
                 statItem = stats.get(serviceKey);
             }
+            // 根据 TPS 限流规则判断是否限制此次调用.
             return statItem.isAllowable(url, invocation);
+        // 不限流
         } else {
+            // 移除 StatItem
             StatItem statItem = stats.get(serviceKey);
             if (statItem != null) {
                 stats.remove(serviceKey);
             }
+            // 返回通过
+            return true;
         }
-
-        return true;
     }
 
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/filter/tps/StatItem.java

@@ -21,17 +21,31 @@ import com.alibaba.dubbo.rpc.Invocation;
 
 import java.util.concurrent.atomic.AtomicInteger;
 
+/**
+ * 统计项
+ */
 class StatItem {
 
+    /**
+     * 统计名，目前使用服务名
+     */
     private String name;
-
-    private long lastResetTime;
-
+    /**
+     * 周期
+     */
     private long interval;
-
-    private AtomicInteger token;
-
+    /**
+     * 限制大小
+     */
     private int rate;
+    /**
+     * 最后重置时间
+     */
+    private long lastResetTime;
+    /**
+     * 当前周期，剩余种子数
+     */
+    private AtomicInteger token;
 
     StatItem(String name, int rate, long interval) {
         this.name = name;
@@ -42,12 +56,14 @@ class StatItem {
     }
 
     public boolean isAllowable(URL url, Invocation invocation) {
+        // 若到达下一个周期，恢复可用种子数，设置最后重置时间。
         long now = System.currentTimeMillis();
         if (now > lastResetTime + interval) {
-            token.set(rate);
-            lastResetTime = now;
+            token.set(rate); // 回复可用种子数
+            lastResetTime = now; // 最后重置时间
         }
 
+        // CAS ，直到或得到一个种子，或者没有足够种子
         int value = token.get();
         boolean flag = false;
         while (value > 0 && !flag) {
@@ -55,6 +71,7 @@ class StatItem {
             value = token.get();
         }
 
+        // 是否成功
         return flag;
     }
 

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/filter/tps/TPSLimiter.java

@@ -19,11 +19,16 @@ package com.alibaba.dubbo.rpc.filter.tps;
 import com.alibaba.dubbo.common.URL;
 import com.alibaba.dubbo.rpc.Invocation;
 
+/**
+ * TPS 限制器接口
+ */
 public interface TPSLimiter {
 
     /**
      * judge if the current invocation is allowed by TPS rule
      *
+     * 根据 tps 限流规则判断是否限制此次调用.
+     *
      * @param url        url
      * @param invocation invocation
      * @return true allow the current invocation, otherwise, return false

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/protocol/AbstractInvoker.java

@@ -137,6 +137,7 @@ public abstract class AbstractInvoker<T> implements Invoker<T> {
         return getInterface() + " -> " + (getUrl() == null ? "" : getUrl().toString());
     }
 
+    @Override
     public Result invoke(Invocation inv) throws RpcException {
         if (destroyed.get()) {
             throw new RpcException("Rpc invoker for service " + this + " on consumer " + NetUtils.getLocalHost()
@@ -150,7 +151,7 @@ public abstract class AbstractInvoker<T> implements Invoker<T> {
         if (attachment != null && attachment.size() > 0) {
             invocation.addAttachmentsIfAbsent(attachment);
         }
-        // 添加自定义的隐士传参
+        // 添加自定义的隐式参数
         Map<String, String> context = RpcContext.getContext().getAttachments();
         if (context != null) {
             invocation.addAttachmentsIfAbsent(context);

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/protocol/ProtocolFilterWrapper.java

@@ -65,22 +65,27 @@ public class ProtocolFilterWrapper implements Protocol {
                 final Invoker<T> next = last;
                 last = new Invoker<T>() {
 
+                    @Override
                     public Class<T> getInterface() {
                         return invoker.getInterface();
                     }
 
+                    @Override
                     public URL getUrl() {
                         return invoker.getUrl();
                     }
 
+                    @Override
                     public boolean isAvailable() {
                         return invoker.isAvailable();
                     }
 
+                    @Override
                     public Result invoke(Invocation invocation) throws RpcException {
                         return filter.invoke(next, invocation);
                     }
 
+                    @Override
                     public void destroy() {
                         invoker.destroy();
                     }

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/proxy/wrapper/StubProxyFactoryWrapper.java

@@ -37,13 +37,20 @@ import java.lang.reflect.Constructor;
 
 /**
  * StubProxyFactoryWrapper
+ *
+ * 存根代理工厂包装器实现类
  */
 public class StubProxyFactoryWrapper implements ProxyFactory {
 
     private static final Logger LOGGER = LoggerFactory.getLogger(StubProxyFactoryWrapper.class);
 
+    /**
+     * ProxyFactory$Adaptive 对象
+     */
     private final ProxyFactory proxyFactory;
-
+    /**
+     * Protocol$Adaptive 对象
+     */
     private Protocol protocol;
 
     public StubProxyFactoryWrapper(ProxyFactory proxyFactory) {
@@ -54,13 +61,17 @@ public class StubProxyFactoryWrapper implements ProxyFactory {
         this.protocol = protocol;
     }
 
+    @Override
     @SuppressWarnings({"unchecked", "rawtypes"})
     public <T> T getProxy(Invoker<T> invoker) throws RpcException {
+        // 获得 Service Proxy 对象
         T proxy = proxyFactory.getProxy(invoker);
-        if (GenericService.class != invoker.getInterface()) {
+        if (GenericService.class != invoker.getInterface()) { // 非泛化引用
+            // 获得 `stub` 配置项
             String stub = invoker.getUrl().getParameter(Constants.STUB_KEY, invoker.getUrl().getParameter(Constants.LOCAL_KEY));
             if (ConfigUtils.isNotEmpty(stub)) {
                 Class<?> serviceType = invoker.getInterface();
+                // `stub = true` 的情况，使用接口 + `Stub` 字符串。
                 if (ConfigUtils.isDefault(stub)) {
                     if (invoker.getUrl().hasParameter(Constants.STUB_KEY)) {
                         stub = serviceType.getName() + "Stub";
@@ -69,13 +80,17 @@ public class StubProxyFactoryWrapper implements ProxyFactory {
                     }
                 }
                 try {
+                    // 加载 Stub 类
                     Class<?> stubClass = ReflectUtils.forName(stub);
                     if (!serviceType.isAssignableFrom(stubClass)) {
                         throw new IllegalStateException("The stub implementation class " + stubClass.getName() + " not implement interface " + serviceType.getName());
                     }
                     try {
+                        // 创建 Stub 对象，使用带 Service Proxy 对象的构造方法
                         Constructor<?> constructor = ReflectUtils.findConstructor(stubClass, serviceType);
                         proxy = (T) constructor.newInstance(new Object[]{proxy});
+
+                        // 【TODO 8033】参数回调
                         //export stub service
                         URL url = invoker.getUrl();
                         if (url.getParameter(Constants.STUB_EVENT_KEY, Constants.DEFAULT_STUB_EVENT)) {
@@ -99,6 +114,7 @@ public class StubProxyFactoryWrapper implements ProxyFactory {
         return proxy;
     }
 
+    @Override
     public <T> Invoker<T> getInvoker(T proxy, Class<T> type, URL url) throws RpcException {
         return proxyFactory.getInvoker(proxy, type, url);
     }

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/support/DelegateExporter.java

@@ -22,6 +22,7 @@ import com.alibaba.dubbo.rpc.Invoker;
 /**
  * DelegateExporter
  */
+@Deprecated // add by 芋艿，并未使用
 public class DelegateExporter<T> implements Exporter<T> {
 
     private final Exporter<T> exporter;

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/support/DelegateInvoker.java

@@ -25,6 +25,7 @@ import com.alibaba.dubbo.rpc.RpcException;
 /**
  * DelegateInvoker
  */
+@Deprecated // add by 芋艿，并未使用
 public abstract class DelegateInvoker<T> implements Invoker<T> {
 
     protected final Invoker<T> invoker;

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/support/MockInvoker.java

@@ -39,6 +39,7 @@ import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
 final public class MockInvoker<T> implements Invoker<T> {
+
     private final static ProxyFactory proxyFactory = ExtensionLoader.getExtensionLoader(ProxyFactory.class).getAdaptiveExtension();
     private final static Map<String, Invoker<?>> mocks = new ConcurrentHashMap<String, Invoker<?>>();
     private final static Map<String, Throwable> throwables = new ConcurrentHashMap<String, Throwable>();
@@ -83,6 +84,7 @@ final public class MockInvoker<T> implements Invoker<T> {
         return value;
     }
 
+    @Override
     public Result invoke(Invocation invocation) throws RpcException {
         String mock = getUrl().getParameter(invocation.getMethodName() + "." + Constants.MOCK_KEY);
         if (invocation instanceof RpcInvocation) {
@@ -217,4 +219,5 @@ final public class MockInvoker<T> implements Invoker<T> {
         //FIXME
         return null;
     }
+
 }
\ No newline at end of file

dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/support/MockProtocol.java

@@ -31,11 +31,14 @@ final public class MockProtocol extends AbstractProtocol {
         return 0;
     }
 
+    @Override
     public <T> Exporter<T> export(Invoker<T> invoker) throws RpcException {
         throw new UnsupportedOperationException();
     }
 
+    @Override
     public <T> Invoker<T> refer(Class<T> type, URL url) throws RpcException {
         return new MockInvoker<T>(url);
     }
+
 }