我正在使用 Spring 批处理应用程序并希望对 stepExecutionContext 使用后期绑定。我在解决我的错误时遇到问题。
以下是我的阅读器，它具有使用后期绑定的 sql 属性：
<bean id="itemReader_S4_JPolicy" class="com.aegonusa.etl.readers.JDBCItemReader" scope="step">
<property name="jobParameters" ref="jobParameters" />
<property name="dataSource" ref="readDataSource" />
<property name="rowMapper">
<bean class="com.aegonusa.etl.readers.ResultSetRowMapper" scope="step" />
</property>
<property name="sql"
value="#{stepExecutionContext['readQuery']}"></property>
</bean>
我在以下类中设置了这个属性（'readQuery'）：
公共类 StepListener 实现 StepExecutionListener {
…………
@Override
public void beforeStep(StepExecution execution) {
String s = "select getdate();
StepSynchronizationManager.getContext().setAttribute("readQuery", s);
..... } ..... }
请注意，我可以使用 jobParameters 进行后期绑定。但是使用 stepExecutionContext，我得到了以下 exc。我在论坛上尝试了很多帖子，但无法解决：
Throwable occurred: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'lazyBindingProxy.itemReader_S4_JPolicy#sysinit' defined in class path resource [Load_InforceToStage.xml]: Initialization of bean failed; nested exception is java.lang.IllegalStateException: Cannot bind to placeholder: stepExecutionContext['readQuery']
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:480)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
at java.security.AccessController.doPrivileged(AccessController.java:224)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
at org.springframework.beans.factory.support.AbstractBeanFactory$2.getObject(AbstractBeanFactory.java:302)
at org.springframework.batch.core.scope.StepScope.get(StepScope.java:150)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
at org.springframework.batch.core.scope.util.PlaceholderTargetSource.getTarget(PlaceholderTargetSource.java:185)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:184)
at $Proxy1.close(Unknown Source)
at org.springframework.batch.item.support.CompositeItemStream.close(CompositeItemStream.java:83)
at org.springframework.batch.core.step.item.ChunkMonitor.close(ChunkMonitor.java:99)
at org.springframework.batch.item.support.CompositeItemStream.close(CompositeItemStream.java:83)
at org.springframework.batch.core.step.tasklet.TaskletStep.close(TaskletStep.java:297)
at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:255)
at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:135)
at org.springframework.batch.core.job.flow.JobFlowExecutor.executeStep(JobFlowExecutor.java:61)
at org.springframework.batch.core.job.flow.support.state.StepState.handle(StepState.java:60)
at org.springframework.batch.core.job.flow.support.SimpleFlow.resume(SimpleFlow.java:144)
at org.springframework.batch.core.job.flow.support.SimpleFlow.start(SimpleFlow.java:124)
at org.springframework.batch.core.job.flow.FlowJob.doExecute(FlowJob.java:135)
at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:281)
at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:120)
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:49)
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:114)
at org.springframework.batch.core.launch.support.CommandLineJobRunner.start(CommandLineJobRunner.java:349)
at org.springframework.batch.core.launch.support.CommandLineJobRunner.main(CommandLineJobRunner.java:574)
at com.ebsadm.lh.LHSHEDToStage.runJob(LHSHEDToStage.java:124)
at com.ebsadm.lh.LHSHEDToStage.main(LHSHEDToStage.java:111)
at com.ebdadm.lh.TestLHSHEDToStage.testInforceLoadToStage(TestLHSHEDToStage.java:28)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
at java.lang.reflect.Method.invoke(Method.java:600)
at junit.framework.TestCase.runTest(TestCase.java:168)
at junit.framework.TestCase.runBare(TestCase.java:134)
at junit.framework.TestResult$1.protect(TestResult.java:110)
at junit.framework.TestResult.runProtected(TestResult.java:128)
at junit.framework.TestResult.run(TestResult.java:113)
at junit.framework.TestCase.run(TestCase.java:124)
at junit.framework.TestSuite.runTest(TestSuite.java:232)
at junit.framework.TestSuite.run(TestSuite.java:227)
at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:79)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
引起：java.lang.IllegalStateException：无法绑定到占位符：在 org.springframework.batch.core.scope.util.PlaceholderTargetSource$1.convertIfNecessary(PlaceholderTargetSource.java:140) 在 org.springframework.beans 的 stepExecutionContext['readQuery'] .factory.support.AbstractAutowireCapableBeanFactory.convertForProperty(AbstractAutowireCapableBeanFactory.java:1294) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1250) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean (AbstractAutowireCapableBeanFactory.java:1010) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:472) ... 50 更多
请帮忙。