How to create static DynamoDB schema with List attribute

Question

StaticTableSchema

@DynamoDbBean
public class Contact {
private String id;
private List<String> pid;
//getters and setter

StaticTableSchema
            .builder(Contact.class).newItemSupplier(Contact::new)
.addAttribute(List.class,
                    a -> a.name("pid").getter(Contact::getPid).setter(Contact::setPid))

When trying :

DynamoDbTable<Contact> mappedTable = enhancedClient.table(tableName,
                Contact.TABLE_SCHEMA);

I get exception

java.lang.ExceptionInInitializerError at com.childcare.service.ContactServiceIntegrationTest.testFindByEmail(ContactServiceIntegrationTest.java:60) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:564) 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.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) 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$2.evaluate(ParentRunner.java:268) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:89) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:541) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209) Caused by: java.lang.IndexOutOfBoundsException: Index: 0 at java.base/java.util.Collections$EmptyList.get(Collections.java:4553) at software.amazon.awssdk.enhanced.dynamodb.DefaultAttributeConverterProvider.findConverter(DefaultAttributeConverterProvider.java:153) at software.amazon.awssdk.enhanced.dynamodb.DefaultAttributeConverterProvider.converterFor(DefaultAttributeConverterProvider.java:133) at software.amazon.awssdk.enhanced.dynamodb.mapper.ImmutableAttribute.converterFrom(ImmutableAttribute.java:167) at software.amazon.awssdk.enhanced.dynamodb.mapper.ImmutableAttribute.resolve(ImmutableAttribute.java:163) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.lambda$new$0(StaticImmutableTableSchema.java:153) at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195) at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1624) at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) at java.base/java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312) at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:734) at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:658) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.(StaticImmutableTableSchema.java:159) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.(StaticImmutableTableSchema.java:77) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema$Builder.build(StaticImmutableTableSchema.java:425) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticTableSchema.(StaticTableSchema.java:66) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticTableSchema.(StaticTableSchema.java:64) at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticTableSchema$Builder.build(StaticTableSchema.java:255) at com.childcare.model.dyanmo.Contact.(Contact.java:334) ... 25 more

Borislav Stoilov Borislav Stoilov · Accepted Answer · 2021-06-11T09:16:06

For SDK v2 use this:

StaticTableSchema
            .builder(Contact.class)
            .newItemSupplier(Contact::new)
            .addAttribute(EnhancedType.listOf(String.class),
                          a -> a.name("pid")
                          .getter(Contact::getPid)
                          .setter(Contact::setPid)
                          .attributeConverter(ListAttributeConverter.builder(EnhancedType.listOf(String.class))
                          .collectionConstructor(ArrayList::new)                           
                          .elementConverter(StringAttributeConverter.create())
                          .build())))

you need to provide the ListAttributeConverter and the StringAttributeConverter inside it so it knows how to converts its elements

How to create static DynamoDB schema with List attribute

1 Answers