clean code; 升级依赖版本；

xxl-job-executor-samples/xxl-job-executor-sample-jfinal/pom.xml

         <dependency>
             <groupId>com.jfinal</groupId>
             <artifactId>jfinal</artifactId>
-            <version>2.0</version>
+            <version>2.2</version>
         </dependency>
 
         <!-- slf4j -->

xxl-job-executor-samples/xxl-job-executor-sample-springboot/src/main/java/com/xxl/job/executor/mvc/controller/IndexController.java

-package com.xxl.job.executor.mvc.controller;
-
-import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
-import org.springframework.stereotype.Controller;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.ResponseBody;
-
-@Controller
-@EnableAutoConfiguration
-public class IndexController {
-
-    @RequestMapping("/")
-    @ResponseBody
-    String index() {
-        return "xxl job executor running.";
-    }
-
-}
+//package com.xxl.job.executor.mvc.controller;
+//
+//import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+//import org.springframework.stereotype.Controller;
+//import org.springframework.web.bind.annotation.RequestMapping;
+//import org.springframework.web.bind.annotation.ResponseBody;
+//
+//@Controller
+//@EnableAutoConfiguration
+//public class IndexController {
+//
+//    @RequestMapping("/")
+//    @ResponseBody
+//    String index() {
+//        return "xxl job executor running.";
+//    }
+//
+//}

xxl-job-executor-samples/xxl-job-executor-sample-springboot/src/main/java/com/xxl/job/executor/service/jobhandler/DemoJobHandler.java

 import com.xxl.job.core.handler.IJobHandler;
 import com.xxl.job.core.handler.annotation.JobHandler;
 import com.xxl.job.core.log.XxlJobLogger;
-import org.springframework.stereotype.Service;
+import org.springframework.stereotype.Component;
 
 import java.util.concurrent.TimeUnit;
 
  * 任务Handler的一个Demo（Bean模式）
  *
  * 开发步骤：
- * 1、继承 “IJobHandler” ；
- * 2、装配到Spring，例如加 “@Service” 注解；
- * 3、加 “@JobHandler” 注解，注解value值为新增任务生成的JobKey的值;多个JobKey用逗号分割;
+ * 1、新建一个继承com.xxl.job.core.handler.IJobHandler的Java类；
+ * 2、该类被Spring容器扫描为Bean实例，如加“@Component”注解；
+ * 3、添加 “@JobHandler(value="自定义jobhandler名称")”注解，注解的value值为自定义的JobHandler名称，该名称对应的是调度中心新建任务的JobHandler属性的值。
  * 4、执行日志：需要通过 "XxlJobLogger.log" 打印执行日志；
  *
  * @author xuxueli 2015-12-19 19:43:36
  */
 @JobHandler(value="demoJobHandler")
-@Service
+@Component
 public class DemoJobHandler extends IJobHandler {
 
 	@Override