我有一个名为UserAdvice的域，它有一个PriceWithPaf类型的变量，其中包含2个变量，它们也是custom-type / class-object。我已经声明了内部对象/变量和父类，它是Domain中的变量@DynamoDBDocument。
最好的部分是我能够在DynamoDB数据库中完全按照我想要的方式保存数据但是当我将数据读回对象时出现以下错误： （我使用的是dynamoDB的spring数据 - 来自github＆amp;这个错误显示在测试用例中 - 我使用的是AmazonDynamoDBLocal）
com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: UserAdvise[averageEntryPrice]; could not unconvert attribute
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperTableModel.unconvert(DynamoDBMapperTableModel.java:271)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.privateMarshallIntoObject(DynamoDBMapper.java:456)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.marshallIntoObjects(DynamoDBMapper.java:484)
at com.amazonaws.services.dynamodbv2.datamodeling.PaginatedScanList.<init>(PaginatedScanList.java:64)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.scan(DynamoDBMapper.java:1458)
at com.amazonaws.services.dynamodbv2.datamodeling.AbstractDynamoDBMapper.scan(AbstractDynamoDBMapper.java:216)
at org.socialsignin.spring.data.dynamodb.core.DynamoDBTemplate.scan(DynamoDBTemplate.java:112)
at org.socialsignin.spring.data.dynamodb.repository.support.SimpleDynamoDBCrudRepository.findAll(SimpleDynamoDBCrudRepository.java:166)
at org.socialsignin.spring.data.dynamodb.repository.support.SimpleDynamoDBCrudRepository.findAll(SimpleDynamoDBCrudRepository.java:43)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:503)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:488)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:460)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:61)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
at com.sun.proxy.$Proxy68.findAll(Unknown Source)
at com.wt.api.write.WDAuthenticationShould.return_200_for_virtual_and_real_advises_and_wallet_amount(WDAuthenticationShould.java:1079)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:73)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:82)
at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
at org.junit.contrib.java.lang.system.EnvironmentVariables$EnvironmentVariablesStatement.evaluate(EnvironmentVariables.java:71)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:73)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:224)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:83)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:68)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:163)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: PriceWithPaf[nonDividendPaf]; could not unconvert attribute
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperTableModel.unconvert(DynamoDBMapperTableModel.java:271)
at com.amazonaws.services.dynamodbv2.datamodeling.StandardModelFactories$Rules$ObjectDocumentMap$1.unconvert(StandardModelFactories.java:603)
at com.amazonaws.services.dynamodbv2.datamodeling.StandardModelFactories$Rules$ObjectDocumentMap$1.unconvert(StandardModelFactories.java:598)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTypeConverter$DelegateConverter.unconvert(DynamoDBTypeConverter.java:109)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTypeConverter$NullSafeConverter.unconvert(DynamoDBTypeConverter.java:128)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTypeConverter$ExtendedConverter.unconvert(DynamoDBTypeConverter.java:88)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperFieldModel.unconvert(DynamoDBMapperFieldModel.java:146)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperFieldModel.unconvertAndSet(DynamoDBMapperFieldModel.java:164)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperTableModel.unconvert(DynamoDBMapperTableModel.java:267)
... 57 more
Caused by: com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: could not invoke null on class com.wt.domain.PriceWithPaf with value 1.0 of type class java.lang.Double
at com.amazonaws.services.dynamodbv2.datamodeling.StandardBeanProperties$MethodReflect.set(StandardBeanProperties.java:136)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperFieldModel.set(DynamoDBMapperFieldModel.java:111)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperFieldModel.unconvertAndSet(DynamoDBMapperFieldModel.java:164)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperTableModel.unconvert(DynamoDBMapperTableModel.java:267)
... 65 more
Caused by: java.lang.NullPointerException
at com.amazonaws.services.dynamodbv2.datamodeling.StandardBeanProperties$MethodReflect.set(StandardBeanProperties.java:133)
... 68 more
答案 0 :(得分：1)
面对此问题并尝试解决3天后。最终遇到这篇文章，它起作用了。
我的错误是：
初始
@DynamoDBAttribute
public String getPeriod() {
return period;
}
public void set_period(String period) {
this.period = period;
}
将其更改为：
@DynamoDBAttribute
public String getPeriod() {
return period;
}
public void setPeriod(String period) {
this.period = period;
}
答案 1 :(得分：0)
它工作 - 错误是由于错误的getter设置 - 其中一个getter假设返回自定义对象（PriceWithPaf）而不是返回double。
这使得dynamoDBDocument的取消映射出错了。
使用DynamoDBDocument很简单 - 只需将此注释放在所有充当Domain Class变量的类上。并确保你的getter和setter是默认/不操作的;）