Spirng_Batch

一、需求分析

使用Spring Batch对XML文件进行读写操作: 从一个xml文件中读取商品信息, 经过简单的处理, 写入另外一个xml文件中.

二、代码实现

1. 代码结构图:

2. applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
  xmlns:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop"
  xmlns:context="http://www.springframework.org/schema/context"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
  http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
  http://www.springframework.org/schema/tx
  http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
  http://www.springframework.org/schema/aop
  http://www.springframework.org/schema/aop/spring-aop-3.1.xsd
  http://www.springframework.org/schema/context
  http://www.springframework.org/schema/context/spring-context-3.1.xsd"
  default-autowire="byName">

  <!-- auto scan path -->
  <context:component-scan base-package="com.zdp" />

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

base-package: 扫描spring注解

jobLauncher: 启动Job

jobRepository: 为Job提供持久化操作

transactionManager: 提供事务管理操作

3. springBatch.xml

<?xml version="1.0" encoding="UTF-8"?>
<bean:beans xmlns="http://www.springframework.org/schema/batch"
  xmlns:bean="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx"
  xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context"
  xmlns:util="http://www.springframework.org/schema/util"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
  http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
  http://www.springframework.org/schema/tx
  http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
  http://www.springframework.org/schema/aop
  http://www.springframework.org/schema/aop/spring-aop-3.1.xsd
  http://www.springframework.org/schema/context
  http://www.springframework.org/schema/context/spring-context-3.1.xsd
  http://www.springframework.org/schema/batch
  http://www.springframework.org/schema/batch/spring-batch-2.1.xsd
  http://www.springframework.org/schema/util
  http://www.springframework.org/schema/util/spring-util.xsd">

  <bean:import resource="applicationContext.xml" />

  <job id="xmlFileReadAndWriterJob">
    <step id="xmlFileReadAndWriterStep">
      <tasklet>
        <chunk reader="xmlReader" writer="xmlWriter" processor="xmlProcessor" commit-interval="10" />
      </tasklet>
    </step>
  </job>

  <!-- XML文件读取 -->
  <bean:bean id="xmlReader" class="org.springframework.batch.item.xml.StaxEventItemReader" scope="step">
    <bean:property name="fragmentRootElementName" value="product" />
    <bean:property name="unmarshaller" ref="tradeMarshaller" />
    <bean:property name="resource" value="file:#{jobParameters['inputFilePath']}" />
  </bean:bean>

  <!-- XML文件写入 -->
  <bean:bean id="xmlWriter" class="org.springframework.batch.item.xml.StaxEventItemWriter" scope="step">
    <bean:property name="rootTagName" value="zdp" />
    <bean:property name="marshaller" ref="tradeMarshaller" />
    <bean:property name="resource" value="file:#{jobParameters['outputFilePath']}" />
  </bean:bean>

  <bean:bean id="tradeMarshaller" class="org.springframework.oxm.xstream.XStreamMarshaller">
    <bean:property name="aliases">
      <util:map id="aliases">
        <bean:entry key="product" value="com.zdp.domain.Product" />
        <bean:entry key="buyDate" value="java.util.Date" />
      </util:map>
    </bean:property>
  </bean:bean>
</bean:beans>

1. Job包含一个Step，Step中包含了基本的读(xmlReader)，处理(xmlProcessor)，写(xmlWriter)。

2. xmlReader配置了xml读操作, resource属性是指定文件路径信息的。知道了文件路径 。 fragmentRootElementName属性是指定根节点名称的.  unmarshaller负责完成解析节点信息，并映射成程序pojo对象。

3. tradeMarshaller为解析xml节点, 其中entry的key指定对应根节点名称product，value指定程序的pojo类，这样，程序就可以将product节点下的子节点与pojo类(P roduct )中的属性去匹配，当匹配到子节点名与pojo类中的属性名相同时，就会将子节点的内容赋值给pojo类的属性。这样就完成了一个根节点的读取，框架会控制循环操作，直到将文件中所有根( product )节点全部读完为止。这样就完成了XML文件的读操作。

4. xmlWriter配置了对XML文件的写操作。resource属性提供文件的路径信息。同时，也是需要知道这个文件的跟节点信息的，rootTagName属性提供根节点名信息。marshaller 把pojo对象转换成XML片段的工具。本文读操作的unmarshaller和写操作的marshaller用的是同一个转换器，因为XStreamMarshaller既提供将节点片段转换为pojo对象功能，同时又提供将pojo对象持久化为xml文件的功能。

4. XMLProcessor

/**
 * XML文件处理类。
 */
@Component("xmlProcessor")
public class XMLProcessor implements ItemProcessor<Product, Product> {
  // XML文件内容处理
  @Override
  public Product process(Product product) throws Exception {
    product.setBuyDate(new Date());
    product.setCustomer(product.getCustomer() + "顾客!");
    product.setId(product.getId() + "_1");
    product.setPrice(product.getPrice() + 1000.0);
    product.setQuantity(product.getQuantity() + 100);
    return product;
  }
}

5. Product

/**
 * 实体产品类
 */
public class Product {
  private String id;
  private int quantity; // 数量
  private double price; // 价格
  private String customer; // 顾客
  private Date buyDate; // 日期
}

6. JobLaunch

/**
 * Test client
 */
public class JobLaunch {

  public static void main(String[] args) {
    ApplicationContext context = new ClassPathXmlApplicationContext("springBatch.xml");
    JobLauncher jobLauncher = (JobLauncher) context.getBean("jobLauncher");
    Job job = (Job) context.getBean("xmlFileReadAndWriterJob");
    try {
      jobLauncher.run(job, new JobParametersBuilder().addString("inputFilePath", "d:\\input.xml")
                               .addString("outputFilePath", "d:\\output.xml")
                               .toJobParameters());
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}

7. input.xml

8.  output.xml

http://www.tuicool.com/articles/NNZbYv3

http://www.dineshonjava.com/2014/03/spring-batch-xml-to-mongodb-database.html http://stackoverflow.com/questions/26462952/how-to-extract-data-from-multiple-xml-files-and-put-it-in-one-xml-file-in-spring?rq=1 http://www.dineshonjava.com/2014/03/spring-batch-xml-to-mongodb-database.html

mutiple: http://www.dineshonjava.com/2014/03/multiresourceitemreader-in-spring-batch.html

override reader http://stackoverflow.com/questions/17448541/multiresourceitemreader-with-a-custom-delegate-keeps-reading-the-same-file