diff --git a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/EnhanceRequireObjectCache.java b/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/EnhanceRequireObjectCache.java
index e6724beb98dc4b1e08bd757fc14fd14eb8f85173..2be967edea5dd87fd587888354daeb63ed5c2aed 100644
--- a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/EnhanceRequireObjectCache.java
+++ b/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;
diff --git a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixCommandConstructorInterceptor.java b/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixCommandConstructorInterceptor.java
index 161fb2cb0b0b6de0ba95e15732bcbd462a6ee02d..a6f4ecd06e8d5fdfbb8cb28a88efab1811c9783a 100644
--- a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixCommandConstructorInterceptor.java
+++ b/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 CommandKey
or CollapserKey
as the
+ * operation name prefix of span when the constructor that the class hierarchy com.netflix.hystrix.HystrixCommand
+ * invoked.
+ *
+ * @author zhang xin
+ */
public class HystrixCommandConstructorInterceptor implements InstanceConstructorInterceptor {
@Override
diff --git a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixPluginsInterceptor.java b/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixPluginsInterceptor.java
index 91a9bf8a93dc135fe3df885de7505aee2d7c256f..d29b62fd4a544e5e266d9523122d675eeaff695f 100644
--- a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/HystrixPluginsInterceptor.java
+++ b/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
diff --git a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/SWExecutionHookWrapper.java b/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/SWExecutionHookWrapper.java
index ec8c824077da6ba6240bf345f5015767e4afa6ad..cc60c4ebd8531e1462df14983d34f6b32b7a5b7e 100644
--- a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/SWExecutionHookWrapper.java
+++ b/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;
diff --git a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixCommandInstrumentation.java b/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixCommandInstrumentation.java
index ade25d491a257fc8ac4665a096e589fecd04ea52..54c2faf72d099eb271c7e08357fc9c850769d41f 100644
--- a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixCommandInstrumentation.java
+++ b/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";
diff --git a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixPluginsInstrumentation.java b/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixPluginsInstrumentation.java
index 0c59115d4ce33e5e09c405b87ebd3fa51410291b..e7b82a9deee4b2a575f969ac9edbce86daa40026 100644
--- a/apm-sniffer/apm-sdk-plugin/hystrix-1.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/hystrix/v1/define/HystrixPluginsInstrumentation.java
+++ b/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
+ * getCommandExecutionHook
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";