In this post under Spring Batch, I will explain how to change skip policy to one of out of the box provided skip policies.

Whenever we use the “skip-limit” attribute and “skippable-exception-classes” element as shown below at line 4 and 5


1   <batch:job id="importEmployees">
2       <batch:step id="readWriteEmployees">
3           <batch:tasklet>
4               <batch:chunk reader="reader" writer="writer" commit-interval="50" skip-limit="200">
5                   <batch:skippable-exception-classes>
6                       <batch:include class="org.springframework.batch.item.file.FlatFileParseException"/>
7                   </batch:skippable-exception-classes>
8               </batch:chunk>
9               <batch:listeners>
10                  <batch:listener ref="mySkipListener"/>
11              </batch:listeners>
12          </batch:tasklet>
13      </batch:step>
14  </batch:job>

Spring Batch internally uses “org.springframework.batch.core.step.skip.LimitCheckingItemSkipPolicy” implementation. This class is one of the out of the box provided skip policies. The others are

1) AlwaysSkipItemSkipPolicy
2) ExceptionClassifierSkipPolicy
3) NeverSkipItemSkipPolicy
4) CompositeSkipPolicy

As part of this example I will show you how to use “AlwaysSkipItemSkipPolicy”.

AlwaysSkipItemSkipPolicy class just skips records which throws exceptions (regardless of type of exception). There is no limit check and a way to specify for which specific exception to skip.

Below is the xml configuration

XML Snippet


1   <bean id="alwaysSkipItemSkipPolicy" class="org.springframework.batch.core.step.skip.AlwaysSkipItemSkipPolicy"/>
2   
3   <batch:job id="importEmployees">
4       <batch:step id="readWriteEmployees">
5           <batch:tasklet>
6               <batch:chunk reader="reader" writer="writer" commit-interval="50" skip-policy="alwaysSkipItemSkipPolicy"/>
7           </batch:tasklet>
8       </batch:step>
9   </batch:job>

In the above xml snippet, at line 1 I create a bean definition for class “AlwaysSkipItemSkipPolicy” with id “alwaysSkipItemSkipPolicy”.

Then I refer to the bean “alwaysSkipItemSkipPolicy” using “skip-policy” attribute at line 6.

In this way, we can use skip policies other than LimitCheckingItemSkipPolicy.

Below is the complete xml code for your reference.

XML code


<?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:batch="http://www.springframework.org/schema/batch"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
                        http://www.springframework.org/schema/batch http://www.springframework.org/schema/batch/spring-batch.xsd">
    
    <bean id="employee" class="package26.Employee" scope="prototype"/>
    
    <bean id="reader" class="org.springframework.batch.item.file.FlatFileItemReader">
        <property name="resource" value="file:FileInput8.txt"/>
        <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,name,status,salary"/>
                    </bean>
                </property>
                <property name="fieldSetMapper">
                    <bean class="org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper">
                        <property name="prototypeBeanName" value="employee"/>
                    </bean>
                </property>
            </bean>
        </property> 
    </bean>
    
    <bean id="writer" class="org.springframework.batch.item.file.FlatFileItemWriter">
        <property name="resource" value="file:FileOutput.txt"/>
        <property name="lineAggregator">
            <bean class="org.springframework.batch.item.file.transform.DelimitedLineAggregator">
                <property name="fieldExtractor">
                    <bean class="org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor">
                        <property name="names" value="id,name,status,salary"/>
                    </bean>
                </property>
            </bean>
        </property>
    </bean>
    
    <bean id="alwaysSkipItemSkipPolicy" class="org.springframework.batch.core.step.skip.AlwaysSkipItemSkipPolicy"/>
    
    <batch:job id="importEmployees">
        <batch:step id="readWriteEmployees">
            <batch:tasklet>
                <batch:chunk reader="reader" writer="writer" commit-interval="50" skip-policy="alwaysSkipItemSkipPolicy"/>
            </batch:tasklet>
        </batch:step>
    </batch:job>
    
    <bean id="transactionManager" class="org.springframework.batch.support.transaction.ResourcelessTransactionManager" />
    
    <bean id="jobRepository" class="org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean">
        <property name="transactionManager" ref="transactionManager"/>
    </bean>
    
    <bean id="jobLauncher" class="org.springframework.batch.core.launch.support.SimpleJobLauncher">
        <property name="jobRepository" ref="jobRepository"/>
    </bean>
</beans>