<dependency> 
    <groupId>com.amazonaws</groupId> 
    <artifactId>aws-java-sdk-core</artifactId> 
    <version>1.11.534</version> 
</dependency> 
<dependency> 
    <groupId>com.amazonaws</groupId> 
    <artifactId>aws-java-sdk-dynamodb</artifactId> 
    <version>1.11.46</version> 
</dependency>

//用户凭证 
private static String AWSAccessKeyId = "xxx"; 
private static String AWSSecretKey = "xxx"; 
//表名 
private static String TABLE_NAME = "xxx"; 
//用户凭证对象 
private static AWSCredentialsProvider awsCredentialsProvider = new AWSCredentialsProvider() { 
　　public void refresh() {} 
　　public AWSCredentials getCredentials() {
   
    return new BasicAWSCredentials(AWSAccessKeyId, AWSSecretKey);} 
}; 
//表的相关对象 
private static AmazonDynamoDB amazonDynamoDBClient = null; 
private static DynamoDBMapper dbMapper = null; 
private static Table table = null;

@DynamoDBTable(tableName = "xxx") 
public class User { 
    private String id = null; 
    private String name = null; 
    private String telephone = null;public User(String id, String name, String telephone) { 
        super(); 
        this.id = id; 
        this.name = name; 
        this.telephone = telephone; 
    }　　//主键 
    @DynamoDBHashKey(attributeName = "Id") 
    public String getId() { 
        return id; 
    } 
 
    public void setId(String id) { 
        this.id = id; 
    } 
 
    public User() { 
    } 
　　//配有索引 userName-index 
    @DynamoDBAttribute(attributeName = "userName") 
    public String getName() { 
        return name; 
    } 
 
    public void setName(String name) { 
        this.name = name; 
    } 
　　//配有索引 telephone-index 
    @DynamoDBAttribute(attributeName = "telephone") 
    public String getTelephone() { 
        return telephone; 
    } 
 
    public void setTelephone(String telephone) { 
        this.telephone = telephone; 
    } 
}        

amazonDynamoDBClient =  AmazonDynamoDBClientBuilder.standard().withCredentials(awsCredentialsProvider).withRegion(Regions.AP_NORTHEAST_1).build(); 
dbMapper = new DynamoDBMapper(amazonDynamoDBClient); 
table = new  DynamoDB(amazonDynamoDBClient).getTable(TABLE_NAME);

public static user getItemById(String id) { 
        return dbMapper.load(User.class, id); 
    }

public static List<User> getItemBykey(String key, String value) {
    
     　　　　//取索引 
        Index index = table.getIndex(key + "-index"); 
        HashMap<String, String> nameMap = new HashMap<String, String>(); 
        nameMap.put("#key", key); 
        HashMap<String, Object> valueMap = new HashMap<String, Object>(); 
        valueMap.put(":value", value);　　　　//创建筛选条件，以map的形式传入key和value，条件只能用 = 号，其他未考证 
        QuerySpec querySpec = new QuerySpec().withKeyConditionExpression("#key = :value").withNameMap(nameMap) 
                .withValueMap(valueMap); 
        ItemCollection<QueryOutcome> items = index.query(querySpec); 
        Iterator<Item> iterator = items.iterator(); 
        Item item = null; 
        List<User> Users = new ArrayList<User>(); 
        while (iterator.hasNext()) { 
            item = iterator.next(); 
            dashButtonUsers.add(new DashButtonUser(item.getString("Id"),item.getString("userName"),item.getString("telephone")); 
        } 
        return Users; 
    }

public static List<User> getItemByTimeRange(Long startTime, Long endTime) { 
        Map<String, AttributeValue> expressionAttributeValues = new HashMap<String, AttributeValue>(); 
        expressionAttributeValues.put(":startTime", new AttributeValue().withN("" + startTime)); 
        expressionAttributeValues.put(":endTime", new AttributeValue().withN("" + endTime));　　　　//筛选条件 
        ScanRequest scanRequest = new ScanRequest().withTableName(TABLE_NAME) 
                .withFilterExpression("startTime >= :startTime and endTime <= :endTime") 
                .withExpressionAttributeValues(expressionAttributeValues); 
        ScanResult result = amazonDynamoDBClient.scan(scanRequest); 
        List<User> users = new ArrayList<User>(); 
        for (Map<String, AttributeValue> item : result.getItems()) {
    
      
                dashButtonUsers.add(new DashButtonUser(/* 略 */)); 
        } 
        return users; 
    }

//删除一条 
public static void deleteItemById(String id) { 
    dbMapper.delete(new DashButtonUser(id, null, null, null, null, null, null)); 
    } 
//删除多条 
public static void deleteBatch(List<User> ids) {
    
     　　//ids[0] -->{"id":"xxx","telephone":null,"name":null} 
    dbMapper.batchDelete(ids); 
    }

//添加、修改一条 
public static void addOrupdateOneItem(User user) { 
        dbMapper.save(user); 
    } 
//添加、修改多条 
public static List<FailedBatch>  addOrUpdateBatch(List<User> users) { 
        return dbMapper.batchSave(users); 
    }