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apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/EnhanceRequireObjectCache.java

@@ -20,6 +20,12 @@ package org.apache.skywalking.apm.plugin.hystrix.v1;
 
 import org.apache.skywalking.apm.agent.core.context.ContextSnapshot;
 
+/**
+ * {@link EnhanceRequireObjectCache} record the prefix operation name of span and {@link ContextSnapshot} object for
+ * tracing.
+ *
+ * @author zhang xin
+ */
 public class EnhanceRequireObjectCache {
     private final String operationNamePrefix;
     private ContextSnapshot contextSnapshot;

apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixCommandConstructorInterceptor.java

@@ -25,6 +25,13 @@ import com.netflix.hystrix.HystrixObservableCommand;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.EnhancedInstance;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceConstructorInterceptor;
 
+/**
+ * {@link HystrixCommandConstructorInterceptor} get <code>CommandKey</code> or <code>CollapserKey</code> as the
+ * operation name prefix of span when the constructor that the class hierarchy <code>com.netflix.hystrix.HystrixCommand</code>
+ * invoked.
+ *
+ * @author zhang xin
+ */
 public class HystrixCommandConstructorInterceptor implements InstanceConstructorInterceptor {
 
     @Override

apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixPluginsInterceptor.java

@@ -18,17 +18,23 @@
 
 package org.apache.skywalking.apm.plugin.hystrix.v1;
 
+import com.netflix.hystrix.strategy.HystrixPlugins;
 import com.netflix.hystrix.strategy.executionhook.HystrixCommandExecutionHook;
 import java.lang.reflect.Method;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.EnhancedInstance;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceMethodsAroundInterceptor;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.MethodInterceptResult;
 
+/**
+ * {@link HystrixPluginsInterceptor} wrapper the {@link HystrixCommandExecutionHook} object by using {@link
+ * SWExecutionHookWrapper} when the {@link HystrixPlugins#getCommandExecutionHook()} method invoked.
+ *
+ * @author zhang xin
+ */
 public class HystrixPluginsInterceptor implements InstanceMethodsAroundInterceptor {
     @Override
     public void beforeMethod(EnhancedInstance objInst, Method method, Object[] allArguments, Class<?>[] argumentsTypes,
         MethodInterceptResult result) throws Throwable {
-
     }
 
     @Override

apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/SWExecutionHookWrapper.java

@@ -26,6 +26,11 @@ import org.apache.skywalking.apm.agent.core.context.trace.AbstractSpan;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.EnhancedInstance;
 import org.apache.skywalking.apm.network.trace.component.ComponentsDefine;
 
+/**
+ * {@link SWExecutionHookWrapper} wrapper the HystrixCommandExecutionHook object for tracing.
+ *
+ * @author zhang xin
+ */
 public class SWExecutionHookWrapper extends HystrixCommandExecutionHook {
     private final HystrixCommandExecutionHook actual;
 

apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixCommandInstrumentation.java

@@ -28,6 +28,13 @@ import org.apache.skywalking.apm.agent.core.plugin.match.ClassMatch;
 import static net.bytebuddy.matcher.ElementMatchers.any;
 import static org.apache.skywalking.apm.agent.core.plugin.match.HierarchyMatch.byHierarchyMatch;
 
+/**
+ * {@link HystrixCommandInstrumentation} represent that the hystrix plugin intercept the constructor in the class that
+ * hierarchy {@link com.netflix.hystrix.HystrixCommand} class by using the {@link org.apache.skywalking.apm.plugin.hystrix.v1.HystrixCommandConstructorInterceptor}
+ * class.
+ *
+ * @author zhangxin
+ */
 public class HystrixCommandInstrumentation extends ClassInstanceMethodsEnhancePluginDefine {
 
     public static final String INTERCEPT_CLASS = "org.apache.skywalking.apm.plugin.hystrix.v1.HystrixCommandConstructorInterceptor";

apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixPluginsInstrumentation.java

@@ -28,6 +28,13 @@ import org.apache.skywalking.apm.agent.core.plugin.match.ClassMatch;
 import static net.bytebuddy.matcher.ElementMatchers.named;
 import static org.apache.skywalking.apm.agent.core.plugin.match.NameMatch.byName;
 
+/**
+ * {@link HystrixPluginsInstrumentation} represent that the hystrix plugin intercept the
+ * <code>getCommandExecutionHook</code> method in the {@link com.netflix.hystrix.strategy.HystrixPlugins} class class by
+ * using the {@link org.apache.skywalking.apm.plugin.hystrix.v1.HystrixCommandConstructorInterceptor} class.
+ *
+ * @author zhangxin
+ */
 public class HystrixPluginsInstrumentation extends ClassInstanceMethodsEnhancePluginDefine {
 
     public static final String INTERCEPT_CLASS = "org.apache.skywalking.apm.plugin.hystrix.v1.HystrixPluginsInterceptor";