学习使用Java配置创建Spring批处理作业(具有多个步骤)。它使用Spring Boot 2,Spring batch 4和H2数据库来执行批处理作业。
项目结构
在这个项目中,我们将创建一个包含两步任务的简单作业,并执行作业以观察日志。工作执行流程将是 -
开始工作
执行任务一
执行任务二
完成工作
Spring Batch Java配置示例
Maven依赖
我们需要包含spring-boot-starter-batch依赖性。Spring批处理依赖于作为持久数据存储的作业存储库。所以我们也需要一个DB。我正在使用H2(内存数据库),它与弹簧批量很好地集成。
pom.xml
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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">
<modelVersion>4.0.0</modelVersion>
<groupId>com.howtodoinjava</groupId>
<artifactId>App</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>App</name>
<url>http://maven.apache.org</url>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.3.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-batch</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>repository.spring.release</id>
<name>Spring GA Repository</name>
<url>http://repo.spring.io/release</url>
</repository>
</repositories>
添加Tasklet
第一步是创建一些任务,这些任务将按某种顺序运行以形成作业。在Spring批处理中,它们被实现为Tasklet。
MyTaskOne.java
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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 MyTaskOne implements Tasklet {
public RepeatStatus execute(StepContribution contribution, ChunkContext chunkContext) throws Exception
{
System.out.println("MyTaskOne start..");
// ... your code
System.out.println("MyTaskOne done..");
return RepeatStatus.FINISHED;
}
}
MyTaskTwo.java
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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 MyTaskTwo implements Tasklet {
public RepeatStatus execute(StepContribution contribution, ChunkContext chunkContext) throws Exception
{
System.out.println("MyTaskTwo start..");
// ... your code
System.out.println("MyTaskTwo done..");
return RepeatStatus.FINISHED;
}
}
Spring批量配置
这是定义所有与作业相关的配置及其执行逻辑的主要步骤。
BatchConfig.java
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import org.springframework.batch.core.Job;
import org.springframework.batch.core.Step;
import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
import org.springframework.batch.core.launch.support.RunIdIncrementer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.howtodoinjava.demo.tasks.MyTaskOne;
import com.howtodoinjava.demo.tasks.MyTaskTwo;
@Configuration
@EnableBatchProcessing
public class BatchConfig {
@Autowired
private JobBuilderFactory jobs;
@Autowired
private StepBuilderFactory steps;
@Bean
public Step stepOne(){
return steps.get("stepOne")
.tasklet(new MyTaskOne())
.build();
}
@Bean
public Step stepTwo(){
return steps.get("stepTwo")
.tasklet(new MyTaskTwo())
.build();
}
@Bean
public Job demoJob(){
return jobs.get("demoJob")
.incrementer(new RunIdIncrementer())
.start(stepOne())
.next(stepTwo())
.build();
}
}
演示
现在我们的简单工作'demoJob'已配置好并准备好执行。当应用程序完全启动时CommandLineRunner,我正在使用接口自动执行作业JobLauncher。
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import org.springframework.batch.core.Job;
import org.springframework.batch.core.JobParameters;
import org.springframework.batch.core.JobParametersBuilder;
import org.springframework.batch.core.launch.JobLauncher;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class App implements CommandLineRunner
{
@Autowired
JobLauncher jobLauncher;
@Autowired
Job job;
public static void main(String[] args)
{
SpringApplication.run(App.class, args);
}
@Override
public void run(String... args) throws Exception
{
JobParameters params = new JobParametersBuilder()
.addString("JobID", String.valueOf(System.currentTimeMillis()))
.toJobParameters();
jobLauncher.run(job, params);
}
}
注意控制台日志。
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o.s.b.c.l.support.SimpleJobLauncher : Job: [SimpleJob: [name=demoJob]] launched with
the following parameters: [{JobID=1530697766768}]
o.s.batch.core.job.SimpleStepHandler : Executing step: [stepOne]
MyTaskOne start..
MyTaskOne done..
o.s.batch.core.job.SimpleStepHandler : Executing step: [stepTwo]
MyTaskTwo start..
MyTaskTwo done..
o.s.b.c.l.support.SimpleJobLauncher : Job: [SimpleJob: [name=demoJob]] completed with
the following parameters: [{JobID=1530697766768}] and the following status: [COMPLETED]
Spring还自动运行配置的批处理作业。要禁用作业的自动运行,您需要spring.batch.job.enabled在application.properties文件中使用属性。