问题描述
我创建了一个Java服务来从dynamodb获取详细信息,它工作正常,但是我的挑战是我将表名硬编码到类文件 @DynamoDbTable 注释中,以便在不同的环境下工作。感觉这不是正确的方法。我在下面提供了我的代码,有人可以帮助我解决问题。
代码示例
public class DynamodbService {
private DynamoDB client;
private DynamoDBMapper objectMapper;
/**
*
* @param client
* @param objectMapper
*/
@Autowired
public DynamodbService(DynamoDB client,DynamoDBMapper objectMapper) {
this.client = client;
this.objectMapper = objectMapper;
}
public List<Dynamodb> findAll() throws Exception {
DynamoDBMapperConfig mapperConfig = new DynamoDBMapperConfig.Builder()
.withTableNameOverride(DynamoDBMapperConfig.TableNameOverride.withTableNameReplacement(""))
.build();
DynamoDBMapper mapper = new DynamoDBMapper(client,mapperConfig);
DynamoDBScanExpression scanExpression = new DynamoDBScanExpression();
List<Dynamodb> scanResult = objectMapper.scan(Dynamodb.class,scanExpression);
return scanResult;
}
}
我的DynamoDB配置
@Configuration
public class DynamoDBconfig {
/**
*
*/
@Value("${amazon.dynamodb.accesskey}")
private String awsAccessKey;
/**
*
*/
@Value("${amazon.dynamodb.secretkey}")
private String awsSecretKey;
@Bean
public AWSCredentials amazonAWSCredentials() {
return new BasicAWSCredentials(aes.getDecryptedvalue(awsAccessKey),aes.getDecryptedvalue(awsSecretKey));
}
/**
*
* @return
*/
@Bean
public DynamoDBMapperConfig dynamoDBMapperConfig() {
return DynamoDBMapperConfig.DEFAULT;
}
/**
*
* @param amazonDynamoDB
* @param config
* @return
*/
@Bean
public DynamoDBMapper dynamoDBMapper(AmazonDynamoDB amazonDynamoDB,DynamoDBMapperConfig config) {
return new DynamoDBMapper(amazonDynamoDB,config);
}
/**
*
* @return
*/
@Bean
public AmazonDynamoDB amazonDynamoDB() {
return AmazonDynamoDBClientBuilder.standard().withCredentials(amazonAWSCredentialsProvider())
.withRegion(Regions.US_EAST_2).build();
}
/**
*
* @return
*/
@Bean
public DynamoDB dynamoDB() {
return new DynamoDB(amazonDynamoDB());
}
/**
*
* @return
*/
public AWSCredentialsProvider amazonAWSCredentialsProvider() {
return new AWsstaticCredentialsProvider(amazonAWSCredentials());
}
}
我的动态引擎服务中的
我无法找出问题所在。如果我在类文件中使用表名,那么如果我尝试使用代码替换表名,则可以正常工作。
解决方法
(oldList,newList) -> {oldList.addAll(newList);return oldList;}
需要AmazonDynamoDB的任何实现,而不是DynamoDB类。
DynamoDBMapper
您只需要在服务中注入DynamoDBMapper。
public DynamoDBMapper(
final AmazonDynamoDB dynamoDB,final DynamoDBMapperConfig config) {
其他选项可能正在使用@Bean
public DynamoDBMapper dynamoDBMapper(AmazonDynamoDB amazonDynamoDB) {
DynamoDBMapperConfig config = new DynamoDBMapperConfig.Builder().withTableNameOverride(TableNameOverride.withTableNameReplacement(tableName))
.build();
return new DynamoDBMapper(amazonDynamoDB,config);
}
类,但在那里您无法使用com.amazonaws.services.dynamodbv2.document.DynamoDB
,您需要重写代码。
DynamoDBScanExpression