com.amazonaws.services.dynamodbv2.datamodeling

Annotation Type DynamoDBAutoGenerated

@Retention(value=RUNTIME)
 @Target(value={TYPE,FIELD,METHOD,ANNOTATION_TYPE})
public @interface DynamoDBAutoGenerated

Annotation to mark a property as using a custom auto-generator.

May be annotated on a user-defined annotation to pass additional properties to the DynamoDBAutoGenerator.

 @DynamoDBHashKey
 @CustomGeneratedKey(prefix="test-") //<- user-defined annotation
 public String getKey()
 

Where,

 @DynamoDBAutoGenerated(generator=CustomGeneratedKey.Generator.class)
 @Retention(RetentionPolicy.RUNTIME)
 @Target({ElementType.METHOD})
 public @interface CustomGeneratedKey {
     String prefix() default "";

     public static class Generator implements DynamoDBAutoGenerator<String> {
         private final String prefix;
         public Generator(final Class<String> targetType, final CustomGeneratedKey annotation) {
             this.prefix = annotation.prefix();
         }
         public Generator() { //<- required if annotating directly
             this.prefix = "";
         }
         @Override
         public DynamoDBAutoGenerateStrategy getGenerateStrategy() {
             return DynamoDBAutoGenerateStrategy.CREATE;
         }
         @Override
         public final String generate(final String currentValue) {
             return prefix + UUID.randomUUID.toString();
         }
     }
 }
 

Alternately, the property/field may be annotated directly (which requires the generator to provide a default constructor),

 @DynamoDBAutoGenerated(generator=CustomGeneratedKey.Generator.class)
 public String getKey()
 

May be used as a meta-annotation.

Required Element Summary

Required Elements

Modifier and Type	Required Element and Description
Class<? extends DynamoDBAutoGenerator>	generator The auto-generator class for this property.

Element Detail

generator

public abstract Class<? extends DynamoDBAutoGenerator> generator

The auto-generator class for this property.