spring cron 定时任务

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• 0 预备知识：cron表达式

  见 《5 参考》一节。

  1 环境

  eclipse mars2 + Maven3.3.9

  2 开发步骤

  项目码云地址

  2.1 建立一个maven工程

  POM如下：

    1 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    2   <modelVersion>4.0.0</modelVersion>
    3   <groupId>com.yeyouluo.spring.timer</groupId>
    4   <artifactId>spring-timer-demo</artifactId>
    5   <version>0.0.1-SNAPSHOT</version>
    6   
    7   <properties>
    8         <spring.version>4.2.6.RELEASE</spring.version>
    9         <slf4j.version>1.7.2</slf4j.version>
   10         <log4j.version>1.2.17</log4j.version>
   11     </properties>
   12     <dependencies>
   13         <dependency>  
   14             <groupId>org.slf4j</groupId>  
   15             <artifactId>slf4j-api</artifactId>  
   16             <version>${slf4j.version}</version>  
   17         </dependency>  
   18         <dependency>  
   19             <groupId>org.slf4j</groupId>  
   20             <artifactId>slf4j-log4j12</artifactId>  
   21             <version>${slf4j.version}</version>  
   22         </dependency>  
   23         <!-- common-logging 实际调用slf4j -->  
   24         <dependency>  
   25             <groupId>org.slf4j</groupId>  
   26             <artifactId>jcl-over-slf4j</artifactId>  
   27             <version>${slf4j.version}</version>  
   28         </dependency>  
   29         <!-- java.util.logging 实际调用slf4j -->  
   30         <dependency>  
   31             <groupId>org.slf4j</groupId>  
   32             <artifactId>jul-to-slf4j</artifactId>  
   33             <version>${slf4j.version}</version>  
   34         </dependency>  
   35         <dependency>  
   36             <groupId>log4j</groupId>  
   37             <artifactId>log4j</artifactId>  
   38             <version>${log4j.version}</version>  
   39         </dependency>  
   40         <dependency>  
   41             <groupId>org.lazyluke</groupId>  
   42             <artifactId>log4jdbc-remix</artifactId>  
   43             <version>0.2.7</version>  
   44         </dependency> 
   45         <!-- spring核心包 -->
   46         <dependency>
   47             <groupId>org.springframework</groupId>
   48             <artifactId>spring-core</artifactId>
   49             <version>${spring.version}</version>
   50         </dependency>
   51         <dependency>
   52             <groupId>org.springframework</groupId>
   53             <artifactId>spring-web</artifactId>
   54             <version>${spring.version}</version>
   55         </dependency>
   56         <dependency>
   57             <groupId>org.springframework</groupId>
   58             <artifactId>spring-tx</artifactId>
   59             <version>${spring.version}</version>
   60         </dependency>
   61         <dependency>
   62             <groupId>org.springframework</groupId>
   63             <artifactId>spring-jdbc</artifactId>
   64             <version>${spring.version}</version>
   65         </dependency>
   66         <dependency>
   67             <groupId>org.springframework</groupId>
   68             <artifactId>spring-webmvc</artifactId>
   69             <version>${spring.version}</version>
   70         </dependency>
   71         <dependency>
   72             <groupId>org.springframework</groupId>
   73             <artifactId>spring-aop</artifactId>
   74             <version>${spring.version}</version>
   75         </dependency>
   76         <dependency>
   77             <groupId>org.springframework</groupId>
   78             <artifactId>spring-beans</artifactId>
   79             <version>${spring.version}</version>
   80         </dependency>
   81         <dependency>
   82             <groupId>org.springframework</groupId>
   83             <artifactId>spring-context</artifactId>
   84             <version>${spring.version}</version>
   85         </dependency>
   86         <dependency>
   87             <groupId>org.springframework</groupId>
   88             <artifactId>spring-context-support</artifactId>
   89             <version>${spring.version}</version>
   90         </dependency>
   91         <dependency>
   92             <groupId>org.springframework</groupId>
   93             <artifactId>spring-expression</artifactId>
   94             <version>${spring.version}</version>
   95         </dependency>
   96         <dependency>
   97               <groupId>org.springframework</groupId>
   98               <artifactId>spring-messaging</artifactId>
   99               <version>${spring.version}</version>
  100         </dependency>
  101         <dependency>
  102              <groupId>org.springframework.integration</groupId>
  103               <artifactId>spring-integration-core</artifactId>
  104               <version>4.2.5.RELEASE</version>
  105         </dependency>
  106         
  107     </dependencies>
  108     
  109     <packaging>jar</packaging>
  110 </project>

  POM.xml

  pom文件中可能加入了很多没有使用的jar，比如和mybatis、druid、mysql-connector相关的jar，以备后用。

  2.2 添加配置文件

  ①log4j.properties

   1 log4j.rootLogger=INFO, Console, RollingFile
   2 #Console
   3 log4j.appender.Console=org.apache.log4j.ConsoleAppender
   4 log4j.appender.Console.layout=org.apache.log4j.PatternLayout
   5 log4j.appender.Console.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n
   6  
   7 #RollingFile
   8 log4j.appender.RollingFile=org.apache.log4j.DailyRollingFileAppender
   9  
  10 log4j.appender.RollingFile.File=logs/log.log
  11 log4j.appender.RollingFile.layout=org.apache.log4j.PatternLayout
  12 log4j.appender.RollingFile.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n

  log4j.xml

②spring-base.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4 xmlns:task="http://www.springframework.org/schema/task"
 5 xmlns:context="http://www.springframework.org/schema/context"
 6 xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 7 http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.0.xsd
 8 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
 9  
10 <bean id="readDBTask" class="com.yeyouluo.spring.timer.service.ReadDBTask"></bean>
11  
12 <task:scheduled-tasks>
13 <task:scheduled ref="readDBTask" method="doSomething" cron="0/3 * * * * ?"/>
14 </task:scheduled-tasks>
15  
16 </beans>

spring-base.xml