Spring batch 入门 详解Spring batch 入门学习教程(附源码)
achuo 人气:0Spring batch 是一个开源的批处理框架.执行一系列的任务. 在 spring batch 中 一个job 是由许多 step 组成的。而每一个 step 又是由 READ-PROCESS-WRITE task或者 单个 task 组成。
1. "READ-PROCESS-WRITE" 处理,根据字面意思理解就可以:
- READ 就是从资源文件里面读取数据,比如从xml文件,csv文件,数据库中读取数据.
- PROCESS 就是处理读取的数据
- WRITE 就是将处理过的数据写入到其他资源文件中去,可以是XML,CSV,或者数据库.
比如:从CSV文件中 读取数据,经过处理之后,保存到数据库. spring batch 提供了很多类去处理这方面的东西。
2.单个task, 也就是处理单个任务。比如在一个step 开始之前或者完成之后清除资源文件等.
3.许多个step 组成在一起,就组成了一个job. 所以他们之间的关系,就如同下面的描述:
一个 job = 很多steps
一个step = 一个READ-PROCESS-WRITE 或者 一个task.
同样一个job = step1 -->step2--step3 这样链表形式的组成.
Spring batch 例子
考虑如下一个批处理的例子,看起来有点啰嗦,只是为了说明用途:
1. step1 : 从 A 文件夹中读取csv 文件,处理之后,写入到B文件夹中(READ-PROCESS-WRITE)
2. step2 : 从 B 文件夹中读取CSV文件 ,处理之后, 存储到数据库中(READ-PROCESS-WRITE).
3. step3 : 删除B文件夹下的CSV文件。(用到单个task)
4. step4 : 从数据库读取数据,处理之后,生成XML报表文件(READ-PROCESS-WRITE).
5. step5 : 读取XML报表,并发送EMAIL给管理员(用到单个task)
用spring batch 我们可以如下定义这个job:
<job id="abcJob" xmlns="http://www.springframework.org/schema/batch"> <step id="step1" next="step2"> <tasklet> <chunk reader="cvsItemReader" writer="cvsItemWriter" processor="itemProcesser" commit-interval="1" /> </tasklet> </step> <step id="step2" next="step3"> <tasklet> <chunk reader="cvsItemReader" writer="databaseItemWriter" processor="itemProcesser" commit-interval="1" /> </tasklet> </step> <step id="step3" next="step4"> <tasklet ref="fileDeletingTasklet" /> </step> <step id="step4" next="step5"> <tasklet> <chunk reader="databaseItemReader" writer="xmlItemWriter" processor="itemProcesser" commit-interval="1" /> </tasklet> </step> <step id="step5"> <tasklet ref="sendingEmailTasklet" /> </step> </job>
整个 job 的执行是存储在数据库中的,所以即使是某一个step出错失败,也不需要全部从头开始执行这个job.下面是一个真正的入门教程例子.
采用 jar包如下:
spring-batch-2.2.3 以上版本,但是我在2.2.3版本中发现 org/springframework/batch/core/schema-mysql.sql 里面的的mysql 创建表的语句是有问题的,也就是少了“," 号导致的问题( NOT NULL, 后面几个创建表的语句NOT NULL 后面少了逗号),当然你可以自己修改后再执行,执行完毕后有如下几个表:
xstream-1.3.jar 必须的。
jettison-1.3.3.jar也是必须的, 否则会出现
java.lang.NoClassDefFoundError: org/codehaus/jettison/mapped/MappedXMLOutputFactory错误。
另外我用的spring 是 3.1 版本的,可以下载相关jar包,还有apache common 相关jar包就可以了。
mysql-connect-java-5.1.jar 连接mysql 数据库用的。
假设要将如下 csv 文件读取出来处理之后,写入到一个xml文件之中.
,"213,100",980,"mkyong", 29/7/2013 ,"320,200",1080,"staff 1", 30/7/2013 ,"342,197",1200,"staff 2", 31/7/2013
用 FlatFileItemReader 去读取CSV 文件, 用 itemProcessor 去处理数据,用 StaxEventItemWriter 去写数据
job 的定义如下(job-hello-world.xml):
<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-3.1.xsd "> <import resource="../config/context.xml" /> <import resource="../config/database.xml" /> <bean id="report" class="yihaomen.model.Report" scope="prototype" /> <bean id="itemProcessor" class="yihaomen.CustomItemProcessor" /> <batch:job id="helloWorldJob"> <batch:step id="step1"> <batch:tasklet> <batch:chunk reader="cvsFileItemReader" writer="xmlItemWriter" processor="itemProcessor" commit-interval="10"> </batch:chunk> </batch:tasklet> </batch:step> </batch:job> <bean id="cvsFileItemReader" class="org.springframework.batch.item.file.FlatFileItemReader"> <property name="resource" value="classpath:cvs/input/report.csv" /> <property name="lineMapper"> <bean class="org.springframework.batch.item.file.mapping.DefaultLineMapper"> <property name="lineTokenizer"> <bean class="org.springframework.batch.item.file.transform.DelimitedLineTokenizer"> <property name="names" value="id,sales,qty,staffName,date" /> </bean> </property> <property name="fieldSetMapper"> <bean class="yihaomen.ReportFieldSetMapper" /> <!-- if no data type conversion, use BeanWrapperFieldSetMapper to map by name <bean class="org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper"> <property name="prototypeBeanName" value="report" /> </bean> --> </property> </bean> </property> </bean> <bean id="xmlItemWriter" class="org.springframework.batch.item.xml.StaxEventItemWriter"> <property name="resource" value="file:xml/outputs/report.xml" /> <property name="marshaller" ref="reportMarshaller" /> <property name="rootTagName" value="report" /> </bean> <bean id="reportMarshaller" class="org.springframework.oxm.jaxb.Jaxb2Marshaller"> <property name="classesToBeBound"> <list> <value>yihaomen.model.Report</value> </list> </property> </bean> </beans>
映射csv文件到 Report 对象并写XML文件 (通过 jaxb annotations).
package yihaomen.model; import java.math.BigDecimal; import java.util.Date; import javax.xml.bind.annotation.XmlAttribute; import javax.xml.bind.annotation.XmlElement; import javax.xml.bind.annotation.XmlRootElement; @XmlRootElement(name = "record") public class Report { private int id; private BigDecimal sales; private int qty; private String staffName; private Date date; @XmlAttribute(name = "id") public int getId() { return id; } public void setId(int id) { this.id = id; } @XmlElement(name = "sales") public BigDecimal getSales() { return sales; } public void setSales(BigDecimal sales) { this.sales = sales; } @XmlElement(name = "qty") public int getQty() { return qty; } public void setQty(int qty) { this.qty = qty; } @XmlElement(name = "staffName") public String getStaffName() { return staffName; } public void setStaffName(String staffName) { this.staffName = staffName; } public Date getDate() { return date; } public void setDate(Date date) { this.date = date; } @Override public String toString() { return "Report [id=" + id + ", sales=" + sales + ", qty=" + qty + ", staffName=" + staffName + "]"; } }
为了转换日期,用了自定义的 FieldSetMapper. 如果没有数据需要转换, BeanWrapperFieldSetMapper 通过名称name 去自动映射值。
package yihaomen; import java.text.ParseException; import java.text.SimpleDateFormat; import org.springframework.batch.item.file.mapping.FieldSetMapper; import org.springframework.batch.item.file.transform.FieldSet; import org.springframework.validation.BindException; import yihaomen.model.Report; public class ReportFieldSetMapper implements FieldSetMapper<Report> { private SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd"); @Override public Report mapFieldSet(FieldSet fieldSet) throws BindException { Report report = new Report(); report.setId(fieldSet.readInt(0)); report.setSales(fieldSet.readBigDecimal(1)); report.setQty(fieldSet.readInt(2)); report.setStaffName(fieldSet.readString(3)); //default format yyyy-MM-dd //fieldSet.readDate(4); String date = fieldSet.readString(4); try { report.setDate(dateFormat.parse(date)); } catch (ParseException e) { e.printStackTrace(); } return report; } }
在写入数据之前调用itemProcessor 处理数据
package yihaomen; import org.springframework.batch.item.ItemProcessor; import yihaomen.model.Report; public class CustomItemProcessor implements ItemProcessor<Report, Report> { @Override public Report process(Report item) throws Exception { System.out.println("Processing..." + item); return item; } }
spring 配置文件和数据库配置文件
<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"> <!-- stored job-meta in memory --> <!-- <bean id="jobRepository" class="org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean"> <property name="transactionManager" ref="transactionManager" /> </bean> --> <!-- stored job-meta in database --> <bean id="jobRepository" class="org.springframework.batch.core.repository.support.JobRepositoryFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="transactionManager" ref="transactionManager" /> <property name="databaseType" value="mysql" /> </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>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:jdbc="http://www.springframework.org/schema/jdbc" 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 http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd"> <!-- connect to MySQL database --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost:3306/test" /> <property name="username" value="root" /> <property name="password" value="" /> </bean> <bean id="transactionManager" class="org.springframework.batch.support.transaction.ResourcelessTransactionManager" /> <!-- create job-meta tables automatically --> <jdbc:initialize-database data-source="dataSource"> <jdbc:script location="org/springframework/batch/core/schema-drop-mysql.sql" /> <jdbc:script location="org/springframework/batch/core/schema-mysql.sql" /> </jdbc:initialize-database> </beans>
运行程序
package yihaomen; 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) { String[] springConfig = { "spring/batch/jobs/job-hello-world.xml" }; ApplicationContext context = new ClassPathXmlApplicationContext(springConfig); JobLauncher jobLauncher = (JobLauncher) context.getBean("jobLauncher"); Job job = (Job) context.getBean("helloWorldJob"); try { JobExecution execution = jobLauncher.run(job, new JobParameters()); System.out.println("Exit Status : " + execution.getStatus()); } catch (Exception e) { e.printStackTrace(); } System.out.println("Done"); } }
运行结果 :
十二月 03, 2013 8:56:24 下午 org.springframework.batch.core.launch.support.SimpleJobLauncher$1 run INFO: Job: [FlowJob: [name=helloWorldJob]] launched with the following parameters: [{}] 十二月 03, 2013 8:56:24 下午 org.springframework.batch.core.job.SimpleStepHandler handleStep INFO: Executing step: [step1] Processing...Report [id=1001, sales=213100, qty=980, staffName=yihaomen] Processing...Report [id=1002, sales=320200, qty=1080, staffName=staff 1] Processing...Report [id=1003, sales=342197, qty=1200, staffName=staff 2] 十二月 03, 2013 8:56:25 下午 org.springframework.batch.core.launch.support.SimpleJobLauncher$1 run INFO: Job: [FlowJob: [name=helloWorldJob]] completed with the following parameters: [{}] and the following status: [COMPLETED] Exit Status : COMPLETED Done
结果生成了output.xml 在你工程目录的 xml 目录下。
整个源代码,除去jar包之后下载:Spring batch 入门教程下载
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