Springboot集成Spring Batch

Spring官网 （https://spring.io/projects/spring-batch#overview)对Spring  Batch的解释:

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　　　　　一个轻量级的、全面的批处理框架，用于开发对企业系统的日常操作至关重要的健壮批处理应用程序。

Spring Batch提供了处理大量记录所必需的可重用功能，包括日志/跟踪、事务管理、作业处理统计信息、

作业重启、跳过和资源管理。它还提供了更高级的技术服务和特性，这些特性将通过优化和分区技术支持极高

容量和高性能的批处理作业。无论简单还是复杂，大容量批处理作业都可以以高度可伸缩的方式利用框架来处

理大量信息。

Features(特性)：

• Transaction management   事务管理
• Chunk based processing    基于块的处理
• Declarative I/O声明式I / O
• Start/Stop/Restart                 启动/停止/启动
• Retry/Skip                              重试/跳过
• Web based administration interface (Spring Cloud Data Flow)       基于Web的管理接口(Spring Cloud Data Flow)

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　　　　Spring batch主要有以下部分组成：

• JobRepository  　　   用来注册job的容器
• JobLauncher              用来启动Job的接口
• Job                               实际执行的任务，包含一个或多个Step
• Step                             step包含ItemReader、ItemProcessor和ItemWriter
• ItemReader                 用来读取数据的接口
• ItemProcessor            用来处理数据的接口
• ItemWriter                   用来输出数据的接口

一个Job有一个或多个Step组成，Step有读、处理、写三部分操作组成；通过JobLauncher启动Job，启动时从

JobRepository获取Job Execution；

当前运行的Job及Step的结果及状态保存在JobRepository中。

下面是Springboot集成Spring Batch 的 一个Demo：

1.在idea下新建一个springboot项目

    pom.xml

    

<?xml version="1.0" encoding="UTF-8"?>
<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">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>springbatch</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>springbatch</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-batch</artifactId>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

ItemReader

public class Reader implements ItemReader<String> {

    private String[] messages = { "篮球之神 Michael Jordan",
                                     "欢迎来到batch示例 Welcome to Spring Batch Example",
                                     "The more time goes by,The more life happens" };

    private int count = 0;

    @Override
    public  String read() throws Exception, UnexpectedInputException, ParseException, NonTransientResourceException{
        if(count<messages.length){
            return messages[count++];
        }else{
            count=0;
        }
        return null;
    }

ItemProcessor

public class Processor implements ItemProcessor<String,String> {
    @Override
    public String process(String data) throws Exception{
        return  data.toUpperCase();
    }
}

ItemWriter

public class Writer implements ItemWriter<String> {

    @Override
    public void write(List<? extends String> messages) throws Exception{
        for(String msg:messages){
            System.out.println("输出信息："+ msg);
        }

    }
}

Listener

public class JobCompletionListener extends JobExecutionListenerSupport {

    @Override
    public void beforeJob(JobExecution jobExecution){
        if(jobExecution.getStatus()== BatchStatus.STARTED){
            System.out.println("批处理执行开始....");
        }
    }
    @Override
    public void afterJob(JobExecution jobExecution){
        if(jobExecution.getStatus()== BatchStatus.COMPLETED){
            System.out.println("批处理执行结束....");
        }

    }
}

Config

@Configuration
public class BatchConfig {

    @Autowired
    public JobBuilderFactory jobBuilderFactory;

    @Autowired
    public StepBuilderFactory stepBuilderFactory;

    @Bean
    public Job processJob(){
        return jobBuilderFactory.get("processJob")
                .incrementer(new RunIdIncrementer()).listener(listener())
                .flow(orderStep1()).end().build();
    }

    @Bean
    public Step orderStep1() {
        return stepBuilderFactory.get("orderStep1").<String, String> chunk(1)
                .reader(new Reader()).processor(new Processor())
                .writer(new Writer()).build();
    }

    @Bean
    public JobExecutionListener listener() {
        return new JobCompletionListener();
    }
}

Controller

@RestController
@EnableScheduling
public class JobInvokerController {

    @Autowired
    JobLauncher jobLauncher;

    @Autowired
    Job processJob;

    //每20秒执行一次
    @Scheduled(cron = "*/20 * *  * * * ")
    public void handle() throws Exception {

        JobParameters jobParameters = new JobParametersBuilder().addLong("time", System.currentTimeMillis())
                .toJobParameters();
        jobLauncher.run(processJob, jobParameters);

    }
}

启动项目：每20秒执行一次批处理

代码地址：https://github.com/liuchunbo24/Springboot-SpringBatch-Demo