com.amazonaws.services.dynamodbv2.model
Class BatchGetItemRequest

java.lang.Object
  com.amazonaws.AmazonWebServiceRequest
      com.amazonaws.services.dynamodbv2.model.BatchGetItemRequest

All Implemented Interfaces:

Serializable

public class BatchGetItemRequest
extends AmazonWebServiceRequest
implements Serializable

Container for the parameters to the BatchGetItem operation.

The BatchGetItem operation returns the attributes of one or more items from one or more tables. You identify requested items by primary key.

A single operation can retrieve up to 1 MB of data, which can comprise as many as 100 items. BatchGetItem will return a partial result if the response size limit is exceeded, the table's provisioned throughput is exceeded, or an internal processing failure occurs. If a partial result is returned, the operation returns a value for UnprocessedKeys . You can use this value to retry the operation starting with the next item to get.

For example, if you ask to retrieve 100 items, but each individual item is 50 KB in size, the system returns 20 items (1 MB) and an appropriate UnprocessedKeys value so you can get the next page of results. If desired, your application can include its own logic to assemble the pages of results into one dataset.

If no items can be processed because of insufficient provisioned throughput on each of the tables involved in the request, BatchGetItem throws ProvisionedThroughputExceededException .

By default, BatchGetItem performs eventually consistent reads on every table in the request. If you want strongly consistent reads instead, you can set ConsistentRead to true for any or all tables.

In order to minimize response latency, BatchGetItem fetches items in parallel.

When designing your application, keep in mind that Amazon DynamoDB does not return attributes in any particular order. To help parse the response by item, include the primary key values for the items in your request in the AttributesToGet parameter.

If a requested item does not exist, it is not returned in the result. Requests for nonexistent items consume the minimum read capacity units according to the type of read. For more information, see Capacity Units Calculations in the Amazon DynamoDB Developer Guide.

See Also:

AmazonDynamoDB.batchGetItem(BatchGetItemRequest), Serialized Form

Constructor Summary

BatchGetItemRequest()

Method Summary

BatchGetItemRequest	addRequestItemsEntry(String key, KeysAndAttributes value) A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve.
BatchGetItemRequest	clearRequestItemsEntries() Removes all the entries added into RequestItems.
boolean	equals(Object obj)
Map<String,KeysAndAttributes>	getRequestItems() A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve.
String	getReturnConsumedCapacity() If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.
int	hashCode()
void	setRequestItems(Map<String,KeysAndAttributes> requestItems) A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve.
void	setReturnConsumedCapacity(ReturnConsumedCapacity returnConsumedCapacity) If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.
void	setReturnConsumedCapacity(String returnConsumedCapacity) If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.
String	toString() Returns a string representation of this object; useful for testing and debugging.
BatchGetItemRequest	withRequestItems(Map<String,KeysAndAttributes> requestItems) A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve.
BatchGetItemRequest	withReturnConsumedCapacity(ReturnConsumedCapacity returnConsumedCapacity) If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.
BatchGetItemRequest	withReturnConsumedCapacity(String returnConsumedCapacity) If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

Methods inherited from class com.amazonaws.AmazonWebServiceRequest

copyPrivateRequestParameters, getRequestClientOptions, getRequestCredentials, setRequestCredentials

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

BatchGetItemRequest

public BatchGetItemRequest()

Method Detail

getRequestItems

public Map<String,KeysAndAttributes> getRequestItems()

A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

Constraints:
Length: 1 - 100

Returns:

A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

setRequestItems

public void setRequestItems(Map<String,KeysAndAttributes> requestItems)

A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

Constraints:
Length: 1 - 100

Parameters:

requestItems - A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

withRequestItems

public BatchGetItemRequest withRequestItems(Map<String,KeysAndAttributes> requestItems)

A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

Returns a reference to this object so that method calls can be chained together.

Constraints:
Length: 1 - 100

Parameters:

requestItems - A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

addRequestItemsEntry

public BatchGetItemRequest addRequestItemsEntry(String key,
                                                KeysAndAttributes value)

A map of one or more table names and, for each table, the corresponding primary keys for the items to retrieve. Each table name can be invoked only once.

Each element in the map consists of the following:

• Keys - An array of primary key attribute values that define specific items in the table.

• AttributesToGet - One or more attributes to be retrieved from the table or index. By default, all attributes are returned. If a specified attribute is not found, it does not appear in the result.

• ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

The method adds a new key-value pair into RequestItems parameter, and returns a reference to this object so that method calls can be chained together.

Constraints:
Length: 1 - 100

Parameters:

key - The key of the entry to be added into RequestItems.

value - The corresponding value of the entry to be added into RequestItems.

clearRequestItemsEntries

public BatchGetItemRequest clearRequestItemsEntries()

Removes all the entries added into RequestItems.

Returns a reference to this object so that method calls can be chained together.

getReturnConsumedCapacity

public String getReturnConsumedCapacity()

If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

Constraints:
Allowed Values: TOTAL, NONE

Returns:

If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

See Also:

ReturnConsumedCapacity

setReturnConsumedCapacity

public void setReturnConsumedCapacity(String returnConsumedCapacity)

If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

Constraints:
Allowed Values: TOTAL, NONE

Parameters:

returnConsumedCapacity - If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

See Also:

ReturnConsumedCapacity

withReturnConsumedCapacity

public BatchGetItemRequest withReturnConsumedCapacity(String returnConsumedCapacity)

If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

Returns a reference to this object so that method calls can be chained together.

Constraints:
Allowed Values: TOTAL, NONE

Parameters:

returnConsumedCapacity - If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

See Also:

ReturnConsumedCapacity

setReturnConsumedCapacity

public void setReturnConsumedCapacity(ReturnConsumedCapacity returnConsumedCapacity)

If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

Constraints:
Allowed Values: TOTAL, NONE

Parameters:

returnConsumedCapacity - If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

See Also:

ReturnConsumedCapacity

withReturnConsumedCapacity

public BatchGetItemRequest withReturnConsumedCapacity(ReturnConsumedCapacity returnConsumedCapacity)

If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

Returns a reference to this object so that method calls can be chained together.

Constraints:
Allowed Values: TOTAL, NONE

Parameters:

returnConsumedCapacity - If set to TOTAL, ConsumedCapacity is included in the response; if set to NONE (the default), ConsumedCapacity is not included.

See Also:

ReturnConsumedCapacity

toString

public String toString()

Returns a string representation of this object; useful for testing and debugging.

Overrides:

toString in class Object

Returns:

A string representation of this object.

See Also:

Object.toString()

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object