diff --git a/src/main/java/a8k/appbean/ecode/AppRet.java b/src/main/java/a8k/appbean/ecode/AppRet.java
index bb7cd07..0d5a4fd 100644
--- a/src/main/java/a8k/appbean/ecode/AppRet.java
+++ b/src/main/java/a8k/appbean/ecode/AppRet.java
@@ -52,7 +52,7 @@ public class AppRet<T> {
 		r.success  = true;
 		r.ecode    = null;
 		r.data     = data;
-		r.dataType = data.getClass().getSimpleName();
+		r.dataType = null == data ? null : data.getClass().getSimpleName();
 		return r;
 	}
 
diff --git a/src/main/java/a8k/hardware/controler/Controler.java b/src/main/java/a8k/hardware/controler/Controler.java
index 8db34a3..ba0c283 100644
--- a/src/main/java/a8k/hardware/controler/Controler.java
+++ b/src/main/java/a8k/hardware/controler/Controler.java
@@ -236,19 +236,8 @@ public class Controler {
 	@ResponseBody
 	public AppRet<Object> serviceActionExecute( @RequestBody Map<String, Object> params ) throws Throwable {
 		String serviceKey = (String)params.get("serviceKey");
-		Class<?> serviceClass = null;
-		var classes = UfClassHelper.getAllClassesInPackage("a8k");
-		for (var clazz : classes) {
-			var hardwareServiceAnnotation = clazz.getAnnotation(HardwareService.class);
-			if (null == hardwareServiceAnnotation || !clazz.getSimpleName().equals(serviceKey)) {
-				continue ;
-			}
-			serviceClass = clazz;
-			break;
-		}
-		if ( null == serviceClass ) {
-			return AppRet.success();
-		}
+		var service = this.getServiceInstanceByServiceKey(serviceKey);
+		assert service != null;
 
 		var actionName = (String)params.get("action");
 		var actionParams = (List<Object>)params.get("params");
@@ -258,7 +247,7 @@ public class Controler {
 			var name = actionParamTypes.get(i);
 			parameterTypes[i] = Class.forName(name);
 		}
-		Method method = serviceClass.getMethod(actionName, parameterTypes);
+		Method method = service.getClass().getMethod(actionName, parameterTypes);
 
 		var parameters = method.getParameters();
 		for ( int i=0; i<parameters.length; i++ ) {
@@ -270,20 +259,30 @@ public class Controler {
 			}
 		}
 
-		var service = UfApplication.getContext().getBean(serviceClass);
+		Object actionResult = null;
 		try {
-			if ( method.getReturnType().equals(Void.TYPE) ) {
-				method.invoke(service, actionParams.toArray());
-				return AppRet.success();
+			var actionParamList = actionParams.toArray();
+
+			var methodAnnotation = method.getAnnotation(HardwareServiceAction.class);
+			var beforeExecute = methodAnnotation.beforeExecute();
+			if ( !beforeExecute.isEmpty() ) {
+				var beforeExecuteMethod = service.getClass().getMethod(beforeExecute, new Class[]{Method.class, List.class});
+				beforeExecuteMethod.invoke(service, method, actionParams);
 			}
-			var actionResult = method.invoke(service, actionParams.toArray());
-			if ( actionResult instanceof AppRet ) {
-				return (AppRet)actionResult;
+
+			if ( method.getReturnType().equals(Void.TYPE) ) {
+				method.invoke(service, actionParamList);
+			} else {
+				actionResult = method.invoke(service, actionParamList);
 			}
-			return AppRet.success(actionResult);
 		} catch ( InvocationTargetException e ) {
 			throw e.getTargetException();
 		}
+
+		if ( actionResult instanceof AppRet ) {
+			return (AppRet<Object>)actionResult;
+		}
+		return AppRet.success(actionResult);
 	}
 
 	@PostMapping("/api/service-config/class-struct-info-get")
@@ -296,6 +295,24 @@ public class Controler {
 		return AppRet.success(struct);
 	}
 
+	// get service instance by service key
+	private Object getServiceInstanceByServiceKey( String serviceKey ) {
+		Class<?> serviceClass = null;
+		var classes = UfClassHelper.getAllClassesInPackage("a8k");
+		for (var clazz : classes) {
+			var hardwareServiceAnnotation = clazz.getAnnotation(HardwareService.class);
+			if (null == hardwareServiceAnnotation || !clazz.getSimpleName().equals(serviceKey)) {
+				continue ;
+			}
+			serviceClass = clazz;
+			break;
+		}
+		if ( null == serviceClass ) {
+			return null;
+		}
+		return UfApplication.getContext().getBean(serviceClass);
+	}
+
 	// get service param handler by given service key
 	private Object getServiceParamHandlerByServiceKey( String serviceKey ) {
 		var classes = UfClassHelper.getAllClassesInPackage("a8k");
diff --git a/src/main/java/a8k/service/hardware/SamplesPreProcessModuleCtrlService.java b/src/main/java/a8k/service/hardware/SamplesPreProcessModuleCtrlService.java
index 3bef7e9..a241f98 100644
--- a/src/main/java/a8k/service/hardware/SamplesPreProcessModuleCtrlService.java
+++ b/src/main/java/a8k/service/hardware/SamplesPreProcessModuleCtrlService.java
@@ -12,6 +12,9 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.stereotype.Component;
 
+import java.lang.reflect.Method;
+import java.util.List;
+
 @Component
 @HardwareService(name = "样本预处理模块")
 @HardwareServiceParams(service = SamplesPreProcessModuleCtrlService.class)
@@ -467,7 +470,11 @@ public class SamplesPreProcessModuleCtrlService implements HardwareCtrlModule {
 	/**
 	 * 气溶胶风扇控制
 	 */
-	@HardwareServiceAction(name = "气溶胶风扇控制", order = 1)
+	@HardwareServiceAction(
+		name = "气溶胶风扇控制",
+		order = 1,
+		beforeExecute="beforeActionExec"
+	)
 	public void setAeroslFanPower(Boolean enable) throws HardwareException, InterruptedException {
 		if (enable) {
 			canBus.fanControlerSetSpeed(MId.WbTubeFanMod, 99);
@@ -475,4 +482,8 @@ public class SamplesPreProcessModuleCtrlService implements HardwareCtrlModule {
 			canBus.fanControlerSetSpeed(MId.WbTubeFanMod, 0);
 		}
 	}
+
+	public void beforeActionExec( Method method, List<Object> params ) {
+		System.out.println("beforeActionExec");
+	}
 }
diff --git a/src/main/java/a8k/utils/HardwareServiceAction.java b/src/main/java/a8k/utils/HardwareServiceAction.java
index 96bbb71..479a7e6 100644
--- a/src/main/java/a8k/utils/HardwareServiceAction.java
+++ b/src/main/java/a8k/utils/HardwareServiceAction.java
@@ -10,4 +10,5 @@ public @interface HardwareServiceAction {
 	String group() default "";
 	int order() default 0;
 	boolean newline() default false;
+	String beforeExecute() default "";
 }