Spring Batch入門程序

本章向您演示如何編輯一個基本的Spring Batch應用程序。 它將簡單地執行一個tasklet來顯示一條消息。

這個Spring Batch應用程序包含以下文件 -

• 配置文件 - 這是一個XML文件，在這個文件定義作業和作業的步驟(如果應用程序也包括讀取器和寫入器，那麼讀取器和寫入器的配置也包含在這個文件中。)
• Context.xml - 在這個文件中，我們將定義像作業存儲庫，作業啓動器和事務管理器的bean。
• Tasklet類 - 在這個類中，編寫處理代碼作業(在這個示例中，它顯示一個簡單的消息)
• Launcher類 - 在這個類中，通過運行Job啓動器來啓動批處理應用程序。

完整的項目目錄結構如下所示 -

jobconfig.xml

以下是這個Spring Batch應用程序示例的配置文件。

<beans xmlns = "http://www.springframework.org/schema/beans" 
   xmlns:batch = "http://www.springframework.org/schema/batch" 
   xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance" 
   xsi:schemaLocation = "http://www.springframework.org/schema/batch 
      http://www.springframework.org/schema/batch/spring-batch-2.2.xsd
      http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans-3.2.xsd "> 
   <import resource="context.xml" />      
   <!-- Defining a bean --> 
   <bean id = "tasklet" class = "com.yiibai.MyTasklet" />  
   <!-- Defining a job--> 
   <batch:job id = "helloWorldJob">  
      <!-- Defining a Step --> 
      <batch:step id = "step1"> 
         <tasklet ref = "tasklet"/>   
      </batch:step>    
   </batch:job>  
</beans>

context.xml

以下是Spring Batch應用程序的context.xml文件內容。

<beans xmlns = "http://www.springframework.org/schema/beans" 
   xmlns:xsi = http://www.w3.org/2001/XMLSchema-instance" 
   xsi:schemaLocation = "http://www.springframework.org/schema/beans 
      http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">  

   <bean id = "jobRepository"   
      class="org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean"> 
      <property name = "transactionManager" ref = "transactionManager" /> 
   </bean>     

   <bean id = "transactionManager" 
      class = "org.springframework.batch.support.transaction.ResourcelessTransactionManager" />  
   <bean id = "jobLauncher" 
      class = "org.springframework.batch.core.launch.support.SimpleJobLauncher"> 
      <property name = "jobRepository" ref = "jobRepository" /> 
   </bean> 
</beans>

MyTasklet.java

以下是顯示簡單消息的Tasklet類。

package com.yiibai;
import org.springframework.batch.core.StepContribution; 
import org.springframework.batch.core.scope.context.ChunkContext;
import org.springframework.batch.core.step.tasklet.Tasklet;
import org.springframework.batch.repeat.RepeatStatus;  

public class MyTasklet implements Tasklet { 

   @Override 
   public RepeatStatus execute(StepContribution arg0, ChunkContext arg1) throws Exception {  
      System.out.println("Hello This is a sample example of spring batch"); 
      return RepeatStatus.FINISHED; 
   } 
}

App.java

以下是啓動批處理過程的代碼。

package com.yiibai;

import org.springframework.batch.core.Job; 
import org.springframework.batch.core.JobExecution; 
import org.springframework.batch.core.JobParameters; 
import org.springframework.batch.core.launch.JobLauncher; 
import org.springframework.context.ApplicationContext; 
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App { 
       public static void main(String[] args)throws Exception { 

          // System.out.println("hello"); 
          String[] springConfig  =  {"context.xml", "jobconfig.xml"};  

          // Creating the application context object  
          ApplicationContext context = new ClassPathXmlApplicationContext(springConfig); 

          // Creating the job launcher 
          JobLauncher jobLauncher = (JobLauncher) context.getBean("jobLauncher"); 

          // Creating the job 
          Job job = (Job) context.getBean("helloWorldJob"); 

          // Executing the JOB 
          JobExecution execution = jobLauncher.run(job, new JobParameters()); 
          System.out.println("Exit Status : " + execution.getStatus()); 
       }    
    }

在執行時，上面的SpringBatch程序將產生以下輸出 -

四月 27, 2018 10:09:54 上午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@26a1ab54: startup date [Fri Apr 27 10:09:54 CST 2018]; root of context hierarchy
四月 27, 2018 10:09:54 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [context.xml]
四月 27, 2018 10:09:54 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [jobconfig.xml]
四月 27, 2018 10:09:54 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [context.xml]
四月 27, 2018 10:09:55 上午 org.springframework.batch.core.launch.support.SimpleJobLauncher afterPropertiesSet
信息: No TaskExecutor has been set, defaulting to synchronous executor.
四月 27, 2018 10:09:55 上午 org.springframework.batch.core.launch.support.SimpleJobLauncher run
信息: Job: [FlowJob: [name=helloWorldJob]] launched with the following parameters: [{}]
四月 27, 2018 10:09:55 上午 org.springframework.batch.core.job.SimpleStepHandler handleStep
信息: Executing step: [step1]
Hello This is a sample example of Spring Batch
四月 27, 2018 10:09:55 上午 org.springframework.batch.core.launch.support.SimpleJobLauncher run
信息: Job: [FlowJob: [name=helloWorldJob]] completed with the following parameters: [{}] and the following status: [COMPLETED]
Exit Status : COMPLETED

以下是糾正/補充內容：

context.xml的第二行約束少了左雙引號 應該改爲   提交時間：2019-08-16