DynamoDBMappingException：没有HASH键的映射 - 即使我已经清楚地映​​射它

Question

好的，所以我看了this post，我看了this other post。这是我的具体问题：

我有一个名为“server”的简单DynamoDB表，其中包含一个分区键“serverName”。这是表格描述：

"table":{
    "attributeDefinitions":[{
        "attributeName":"serverName","attributeType":"S"
    }],
    "tableName":"server",
    "keySchema":[{
        "attributeName":"serverName","keyType":"HASH"
    }],
    "tableStatus":"ACTIVE",
    "creationDateTime":"Jul 29, 2017 12:46:36 PM",
    "provisionedThroughput":{
        "numberOfDecreasesToday":0,
        "readCapacityUnits":5,
        "writeCapacityUnits":5
    }
}

我有一个Java表定义，如下所示：

@DynamoDBTable(tableName="server")
public static class Server {
    private String serverName;
    private Room[] rooms;

    Server() {}

    Server(String serverName) {
        this.serverName = serverName;
        this.setRooms();
    }

    @DynamoDBHashKey(attributeName="serverName")
    String getServerName() {
        return serverName;
    }
    void setServerName(String serverName) {
        this.serverName = serverName;
    }
    .
    .
    .
}

你可以在描述中看到我的HASH属性为“serverName”，在我的Java表定义中有一个@DynamoDBHashKey(attributeName="serverName")。

有人可以帮我弄清楚为什么我仍然得到......

com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: Server; no mapping for HASH key
    at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperTableModel.hashKey(DynamoDBMapperTableModel.java:119) ~[aws-java-sdk-dynamodb-1.11.105.jar!/:na]
    at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapperTableModel$Builder.build(DynamoDBMapperTableModel.java:449) ~[aws-java-sdk-dynamodb-1.11.105.jar!/:na]
    at com.amazonaws.services.dynamodbv2.datamodeling.StandardModelFactories$StandardTableFactory.getTable(StandardModelFactories.java:107) ~[aws-java-sdk-dynamodb-1.11.105.jar!/:na]
    at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.getTableModel(DynamoDBMapper.java:393) ~[aws-java-sdk-dynamodb-1.11.105.jar!/:na]
    at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.load(DynamoDBMapper.java:431) ~[aws-java-sdk-dynamodb-1.11.105.jar!/:na]
    at com.amazonaws.services.dynamodbv2.datamodeling.AbstractDynamoDBMapper.load(AbstractDynamoDBMapper.java:80) ~[aws-java-sdk-dynamodb-1.11.105.jar!/:na]
    at com.animationlibationstudios.channel.inventory.persist.dynamodb.ServerDynamoRepository.readServer(ServerDynamoRepository.java:110) ~[classes!/:na]
    at com.animationlibationstudios.channel.inventory.persist.dynamodb.ServerDynamoRepository.readServer(ServerDynamoRepository.java:26) ~[classes!/:na]

（p.s。我正在使用JDK 8和com.amazonaws：aws-java-sdk-dynamodb：1.11.105）

Answer 1

<强>更新

你的＆＃34; getServerName＆＃34;方法不公开，DynamoDBMapper偶然发现它。公开它应该有效：

@DynamoDBHashKey(attributeName="serverName")
public String getServerName() {
    return serverName;
}

原始答案：

确保您已创建具有正确分区键定义的表，该定义具有＆＃34; serverName＆＃34;作为相同类型的分区键。

以下是如何操作：

DynamoDBMapper dynamoDBMapper = new DynamoDBMapper(dynamoDB);
CreateTableRequest createTableRequest = dynamoDBMapper.generateCreateTableRequest(itemClass);
// Set your throughput here
createTableRequest.withProvisionedThroughput(new ProvisionedThroughput(1L, 1L));

dynamoDB.createTable(createTableRequest);