spring task @Scheduled注解各参数的用法

@Scheduled (fixedDelay = 5000 ) //上一次执行完毕时间点之后5秒再执行

@Scheduled (fixedDelayString = "${time.fixedDelay}" )

void testFixedDelayString() {

     System.out.println( "Execute at " + System.currentTimeMillis());

}

@Scheduled (fixedRate = 5000 ) //上一次开始执行时间点之后5秒再执行

@Scheduled (initialDelay= 1000 , fixedRate= 5000 ) //第一次延迟1秒后执行，之后按fixedRate的规则每5秒执行一次

/**

  * An annotation that marks a method to be scheduled. Exactly one of

  * the {@link #cron()}, {@link #fixedDelay()}, or {@link #fixedRate()}

  * attributes must be specified.

  *

  * <p>The annotated method must expect no arguments. It will typically have

  * a {@code void} return type; if not, the returned value will be ignored

  * when called through the scheduler.

  *

  * <p>Processing of {@code @Scheduled} annotations is performed by

  * registering a {@link ScheduledAnnotationBeanPostProcessor}. This can be

  * done manually or, more conveniently, through the {@code <task:annotation-driven/>}

  * element or @{@link EnableScheduling} annotation.

  *

  * <p>This annotation may be used as a <em>meta-annotation</em> to create custom

  * <em>composed annotations</em> with attribute overrides.

  *

  * @author Mark Fisher

  * @author Dave Syer

  * @author Chris Beams

  * @since 3.0

  * @see EnableScheduling

  * @see ScheduledAnnotationBeanPostProcessor

  * @see Schedules

  */

@Target ({ElementType.METHOD, ElementType.ANNOTATION_TYPE})

@Retention (RetentionPolicy.RUNTIME)

@Documented

@Repeatable (Schedules. class )

public @interface Scheduled {

     /**

      * A cron-like expression, extending the usual UN*X definition to include

      * triggers on the second as well as minute, hour, day of month, month

      * and day of week.  e.g. {@code "0 * * * * MON-FRI"} means once per minute on

      * weekdays (at the top of the minute - the 0th second).

      * @return an expression that can be parsed to a cron schedule

      * @see org.springframework.scheduling.support.CronSequenceGenerator

      */

     String cron() default "" ;

     /**

      * A time zone for which the cron expression will be resolved. By default, this

      * attribute is the empty String (i.e. the server's local time zone will be used).

      * @return a zone id accepted by {@link java.util.TimeZone#getTimeZone(String)},

      * or an empty String to indicate the server's default time zone

      * @since 4.0

      * @see org.springframework.scheduling.support.CronTrigger#CronTrigger(String, java.util.TimeZone)

      * @see java.util.TimeZone

      */

     String zone() default "" ;

     /**

      * Execute the annotated method with a fixed period in milliseconds between the

      * end of the last invocation and the start of the next.

      * @return the delay in milliseconds

      */

     long fixedDelay() default - 1 ;

     /**

      * Execute the annotated method with a fixed period in milliseconds between the

      * end of the last invocation and the start of the next.

      * @return the delay in milliseconds as a String value, e.g. a placeholder

      * @since 3.2.2

      */

     String fixedDelayString() default "" ;

     /**

      * Execute the annotated method with a fixed period in milliseconds between

      * invocations.

      * @return the period in milliseconds

      */

     long fixedRate() default - 1 ;

     /**

      * Execute the annotated method with a fixed period in milliseconds between

      * invocations.

      * @return the period in milliseconds as a String value, e.g. a placeholder

      * @since 3.2.2

      */

     String fixedRateString() default "" ;

     /**

      * Number of milliseconds to delay before the first execution of a

      * {@link #fixedRate()} or {@link #fixedDelay()} task.

      * @return the initial delay in milliseconds

      * @since 3.2

      */

     long initialDelay() default - 1 ;

     String initialDelayString() default "" ;

}

< context:annotation-config /> 

<!--spring扫描注解的配置   -->

< context:component-scan base-package = "com.baodian.bdweb.timer" />

<!--  开启这个配置，spring才能识别@Scheduled注解     -->

< task:annotation-driven scheduler = "qbScheduler" mode = "proxy" /> 

< task:scheduler id = "qbScheduler" pool-size = "10" />

@Component ( "Taskaa" )

public class Taskaa{

  @Scheduled (cron = "01 50 15 * * ?" )

  public void show(){

   SimpleDateFormat s = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );

   System.out.println( "Taskaa:" +s.format( new Date())); 

  }

}<pre name= "code" class = "java" > @Component ( "Taskbb" )

public class Taskbb{

  @Scheduled (cron = "01 49 15 * * ?" )

  public void show(){

   SimpleDateFormat s = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );

   System.out.println( "Taskbb:" +s.format( new Date())); 

  }

}

< context:annotation-config /> 

<!--spring扫描注解的配置   -->

< context:component-scan base-package = "com.baodian.bdweb.timer" />

< bean id = "Taskaa" class = "com.baodian.bdweb.timer.Taskaa" /> 

< bean id = "Taskbb" class = "com.baodian.bdweb.timer.Taskbb" /> 

< task:scheduled-tasks > 

      < task:scheduled ref = "Taskaa" method = "show" cron = "01 38 15 * * ?" /> 

      < task:scheduled ref = "Taskbb" method = "show" cron = "01 39 15 * * ?" />

</ task:scheduled-tasks >

@Component ( "Taskaa" )

public class Taskaa{

  @Scheduled

  public void show(){

   SimpleDateFormat s = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );

   System.out.println( "Taskaa:" +s.format( new Date())); 

  }

}

@Component ( "Taskbb" )

public class Taskbb{

  @Scheduled

  public void show(){

   SimpleDateFormat s = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );

   System.out.println( "Taskbb:" +s.format( new Date())); 

  }

}