InvalidDataAccessResourceUsageException: Unexpected cursor position change

Question

Encountered the following exception when trying to read from Database in a Spring Batch Application. Any insight would be helpful. This is caused when using a JdbcCursorItemReader. The application works fine using a JdbcPagingItemReader.

Also is it needed to close up any resources (cursors etc.) explicitly when using a JdbcCursorItemReader? If so, how do we do it?

SEVERE: Encountered an error executing the step
    org.springframework.dao.InvalidDataAccessResourceUsageException: Unexpected cursor position change.
        at org.springframework.batch.item.database.AbstractCursorItemReader.verifyCursorPosition(AbstractCursorItemReader.java:365)
        at org.springframework.batch.item.database.AbstractCursorItemReader.doRead(AbstractCursorItemReader.java:449)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:601)
        at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:695)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
        at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:132)
        at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:120)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
        at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631)
        at com.testapp.springbatchtest.io.DataExtractCursorItemReader$$EnhancerByCGLIB$$748012e7.doRead(<generated>)
        at org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader.read(AbstractItemCountingItemStreamItemReader.java:83)
        at org.springframework.batch.core.step.item.SimpleChunkProvider.doRead(SimpleChunkProvider.java:91)
        at org.springframework.batch.core.step.item.SimpleChunkProvider.read(SimpleChunkProvider.java:155)
        at org.springframework.batch.core.step.item.SimpleChunkProvider$1.doInIteration(SimpleChunkProvider.java:114)
        at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:368)
        at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215)
        at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144)
        at org.springframework.batch.core.step.item.SimpleChunkProvider.provide(SimpleChunkProvider.java:108)
        at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:69)
        at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:395)
        at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:131)
        at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:267)
        at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:77)
        at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:368)
        at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215)
        at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144)
        at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:253)
        at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:195)
        at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:137)
        at org.springframework.batch.core.job.AbstractJob.handleStep(AbstractJob.java:380)
        at org.springframework.batch.core.job.SimpleJob.doExecute(SimpleJob.java:124)
        at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:301)
        at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:134)
        at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:49)
        at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:127)

Following is the Sample Code for bean declaration. DataExtractCursorItemReader extends JdbcCursorItemReader.

@Bean
@StepScope
public DataExtractCursorItemReader cursorReaderBean() throws Exception {
    DataExtractCursorItemReader dataExtractReader = new DataExtractCursorItemReader();
    dataExtractReader.setDataSource(dataSource);
    dataExtractReader.setSql("SELECT * FROM SAMPLETABLE");
    dataExtractReader.setFetchSize(500);
    dataExtractReader.setRowMapper(new DataExtractRowMapper());

    return dataExtractReader;
}

Solution 1

verifyCursorPosition property is(seems) just a check to prevent index menipulating by user when subclassing reader; maybe is your case or maybe on some DB platform properties doesn't work.

You can disable it and all should work fine - it's just a test to prevent subclassing.
Check your code if you modify cursor position or check if test fails due to database driver.

Solution 2

I saw this error in case where there are multiple threads acting on a database reader and reader is not thread-safe typically JDBCCursorItemReader vs JDBCPagingItemReader

Solution 3

verifyCursorPosition check depends on java.sql.ResultSet::getRow(). "Support for the getRow method is optional for ResultSets with a result set type of TYPE_FORWARD_ONLY" according to the JavaDoc

You could try to change driver, type of ResultSet (Reader), or follow above suggestion to disable verifyCursorPosition

Comments

[ram]

Do you mean subclassing AbstractCursorItemReader? As mentioned in the question, DataExtractCursorItemReader does extend JdbcCursorItemReader. Any idea why the default is set to TRUE?

[Luca Basso Ricci]

IMO to prevent (unwanted) resultset cursor manipulation by user when subclassing reader. but can also doesn't work due to unsupported feature by database driver (try to set is to false and check result). Do you need subclassing reader?

[ram]

It's resolved by setting the property to false. Thought to verify if its OK to set it to false in case no cursor manipulation is done[in code].

[RBz]

multiple threads also cause this issue I believe. Could you address that scenario in your answer?