Junky's IT Notebook

Spring in Action 筆記V -- 使用Spring來發郵件和執行定時任務

這次來看看Spring提高的一些有用過的JEE中使用到的功能,如 發送Email, 執行定時任務...

先來看看發送Email吧, 在Spring中發送Email是很簡單的,使用Spring提高的MailSender和MailMessage就可以了,配置代碼如下:

<?

xml version = "1.0" encoding = "UTF-8" ?>

<!

DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "spring-beans.dtd" >

<

beans >

< bean id = "mailSender" class = "org.springframework.mail.javamail.JavaMailSenderImpl" >

< property name = "host" >

?

< value > smtp.163.com </ value >

</ property >

< property name = "javaMailProperties" >

?

< props >

??? <!-- 如果要使用用戶名和密碼驗證,這一步需要 -->

??? < prop key = "mail.smtp.auth" > true </ prop >

? </ props >

</ property >

< property name = "username" >

< value > 你的Email地址 </ value >

</ property >

< property name = "password" >

< value > 你的Email密碼 </ value >

</ property >

</ bean >

<!-- 簡單的message -->

< bean id = "mailMessage" class = "org.springframework.mail.SimpleMailMessage" >

< property name = "to" >

< value > 收件人地址 </ value >

</ property >

< property name = "from" >

< value > 你的地址 </ value >

</ property >

< property name = "subject" > <!-- Email 標題 -->

< value > A Spring Mail sender </ value >

</ property >

</ bean >

<!-- 測試發送的類 -->

< bean id = "testMailSender" class = "test.mail.TestSenderMail" >

< property name = "mailMessage" >

< ref bean = "mailMessage" />

</ property >

< property name = "mailSender" >

< ref bean = "mailSender" />

</ property >

</ bean >

</

beans >

上面的配置好以后就可以直接發送了, 看看TestSenderMail.java的代碼:

package? test.mail;

import? org.springframework.mail.MailException;
import? org.springframework.mail.MailSender;
import? org.springframework.mail.SimpleMailMessage;

public?class? TestSenderMail?{
?? private? MailSender?mailSender;
?? private? SimpleMailMessage?mailMessage;
??
?? public? TestSenderMail()?{
????
?? }
??
?? public? SimpleMailMessage?getMailMessage()?{
???? return? mailMessage;
?? }
?? public?void? setMailMessage(SimpleMailMessage?mailMessage)?{
???? this .mailMessage?=?mailMessage;
?? }
?? public? MailSender?getMailSender()?{
???? return? mailSender;
?? }
?? public?void? setMailSender(MailSender?mailSender)?{
???? this .mailSender?=?mailSender;
?? }
??
?? public?void? sendMail()?{
???? SimpleMailMessage?message?=? new? SimpleMailMessage(mailMessage);
??? ?//設置email內容,
???? message.setText( "測試Spring?發送Email." );
????
???? try? {
?????? mailSender.send(message);
???? }? catch? (MailException?e)?{
?????? //?TODO?Auto-generated?catch?block
?????? System.out.println( "O?.?發送Email失敗了...." );
?????? e.printStackTrace();
???? }
?? }
}

很簡單吧. 下面是測試類: TestApp.java

package? test.mail;

import? org.springframework.context.ApplicationContext;
import? org.springframework.context.support.ClassPathXmlApplicationContext;

public?class? TestApp?{

?? /**
??? *? @param? args
??? */
?? public?static?void? main(String[]?args)?{
???? //?TODO?Auto-generated?method?stub
???? ApplicationContext?context?=? new? ClassPathXmlApplicationContext(
???????? "test/mail/mail.xml" );

???? TestSenderMail?sender?=?(TestSenderMail)?context
???????? .getBean( "testMailSender" );
???? sender.sendMail();
?? }
?? //拋出如下異常,是瑞星監控的問題,關閉就可以了
?? /**
??? *?DEBUG?SMTP:?QUIT?failed?with?250?O?.?發送Email失敗了....
??? *?org.springframework.mail.MailSendException:?Could?not?send?mails:?354
??? *?
??? *?com.sun.mail.smtp.SMTPSendFailedException:?354
??? *?
??? *?at
??? *?com.sun.mail.smtp.SMTPTransport.issueSendCommand(SMTPTransport.java:1388)
??? *?at?com.sun.mail.smtp.SMTPTransport.finishData(SMTPTransport.java:1215)?at
??? *?com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:586)
??? */
}

呵呵, 現在就可以發送Email了. It's easy

和發送Email比起來,定時任務更簡單了, 只要實現TimerTask類,提供一個執行的任務,然后使用Spring的任務調度類來設置執行的參數,再使用任務觸發器來激活任務就可以了.

定義一個任務是很簡單的實現TimerTask的run方法就可以了.

如下:SayHelloTask.java

package? test.timerTask;

import? java.util.TimerTask;

public?class? SayHelloTask? extends? TimerTask?{

?? @Override
?? public?void? run()?{
???? //?TODO?Auto-generated?method?stub
???? System.out.println( "測試TimerTask?:?Hello?!!" );
?? }

}

然后是配置文件:

<?

xml version = "1.0" encoding = "UTF-8" ?>

<!

DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "spring-beans.dtd" >

<

beans >

< bean id = "sayHelloTask" class = "test.timerTask.SayHelloTask" ></ bean >

< bean id = "scheduledTask" class = "org.springframework.scheduling.timer.ScheduledTimerTask" >

< property name = "timerTask" >

< ref bean = "sayHelloTask" />

</ property >

<!-- 任務執行周期 2m 關于一些任務的參數請參考JDK doc文檔和Spring相關文檔-->

< property name = "period" >

< value > 2000 </ value >

</ property >

<!-- 延時1m 執行任務 -->

< property name = "delay" >

< value > 1000 </ value >

</ property >

</ bean >

<!-- 啟動定時器 -->

< bean id = "timerBean" class = "org.springframework.scheduling.timer.TimerFactoryBean" >

< property name = "scheduledTimerTasks" >

< list >

< ref bean = "scheduledTask" />

</ list >

</ property >

</ bean >

</

beans >

測試類如下:TestApp.java

package? test.timerTask;

import? org.springframework.context.ApplicationContext;
import? org.springframework.context.support.ClassPathXmlApplicationContext;

public?class? TestApp?{

?? /**
??? *? @param? args
??? */
?? public?static?void? main(String[]?args)?{
???? //?TODO?Auto-generated?method?stub
????ApplicationContext?context?=?new?ClassPathXmlApplicationContext("test/timerTask/javaTimer.xml");
?// ??? ApplicationContext?context2?=? new? ClassPathXmlApplicationContext( "test/timerTask/quartzTimer.xml" );
?? }
// 只要加載配置文件就可以了,
}

使用Java中的定時器比較簡單,其提供的任務也比較簡單, 下面來看看使用quartz來執行一個復雜的任務.

首先制定一個任務, 實現QuartzJobBean中的方法.

package? test.timerTask;

import? org.quartz.JobExecutionContext;
import? org.quartz.JobExecutionException;
import? org.springframework.scheduling.quartz.QuartzJobBean;

public?class? SayHelloTaskUsingQuartz? extends? QuartzJobBean?{

?? @Override
?? protected?void? executeInternal(JobExecutionContext?context)
?????? throws? JobExecutionException?{
???? //?TODO?Auto-generated?method?stub
???? System.out.println( "使用Quartz?認為調度:?Hello!!" );
?? }

}

配置代碼如下:quartzTimer.xml

<?

xml version = "1.0" encoding = "UTF-8" ?>

<!

DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "spring-beans.dtd" >

<

beans >

< bean id = "sayHelloJob" class = "org.springframework.scheduling.quartz.JobDetailBean" >

< property name = "jobClass" >

< value > test.timerTask.SayHelloTaskUsingQuartz </ value >

</ property >

</ bean >

<!-- 關鍵在如下兩個觸發器的配置 -->

<!-- 類似于Java的簡單觸發器 -->

< bean id = "helloTrigger" class = "org.springframework.scheduling.quartz.SimpleTriggerBean" >

< property name = "jobDetail" >

< ref bean = "sayHelloJob" />

</ property >

< property name = "startDelay" >

< value > 1000 </ value >

</ property >

< property name = "repeatInterval" >

< value > 3000 </ value >

</ property >

</ bean >

<!-- 復雜觸發器 -->

< bean id = "helloCronTrigger" class = "org.springframework.scheduling.quartz.CronTriggerBean" >

< property name = "jobDetail" >

< ref bean = "sayHelloJob" />

</ property >

< property name = "cronExpression" >

<!-- 關鍵在配置此表達式 -->

< value > 0 49 15 * * ? </ value >

</ property >

</ bean >

< bean id = "scheduler" class = "org.springframework.scheduling.quartz.SchedulerFactoryBean" >

< property name = "triggers" >

< ref bean = "helloCronTrigger" />

</ property >

</ bean >

</

beans >

關于簡單觸發器和復雜觸發器,查考下面的解釋:

Quartz設計者做了一個設計選擇來從調度分離開作業。Quartz中的觸發器用來告訴調度程序作業什么時候觸發。框架提供了一把觸發器類型，但兩個最常用的是SimpleTrigger和CronTrigger。SimpleTrigger為需要簡單打火調度而設計。典型地，如果你需要在給定的時間和重復次數或者兩次打火之間等待的秒數打火一個作業，那么SimpleTrigger適合你。另一方面，如果你有許多復雜的作業調度，那么或許需要CronTrigger。

CronTrigger是基于Calendar-like調度的。當你需要在除星期六和星期天外的每天上午10點半執行作業時，那么應該使用CronTrigger。正如它的名字所暗示的那樣，CronTrigger是基于Unix克隆表達式的。

作為一個例子，下面的Quartz克隆表達式將在星期一到星期五的每天上午10點15分執行一個作業。
0 15 10 ? * MON-FRI

下面的表達式
0 15 10 ? * 6L 2002-2005
將在2002年到2005年的每個月的最后一個星期五上午10點15分執行作業。

你不可能用SimpleTrigger來做這些事情。你可以用兩者之中的任何一個，但哪個跟合適則取決于你的調度需要。

更多詳細介紹參考此處:

關于cronExpression的介紹:

　

Spring in Action 中提到的Spring就先看到這里了,Spring提供的其他的東西,如RPC , WebWork 等. 有些現在用不到, 有些使用其他的會更好, 用不到的等用到的時候在看了, 如 RPC, 對于WebWork我還是喜歡使用JSF, 好了,該Spring in action 筆記暫時就結束了.

總體感覺Spring 提供的很多功能還是很好用的.其AoP功能雖然還沒有用到, 但也是很好用的一個功能, 說不定明天就要使用了, 呵呵, who knows.

posted on 2006-05-31 23:04 junky 閱讀(1971) 評論(2)  編輯  收藏 所屬分類: spring