com.amazonaws.services.dynamodbv2.document

Class ItemUtils

java.lang.Object

com.amazonaws.services.dynamodbv2.document.ItemUtils

public final class ItemUtils
extends Object

Various utilities for manipulating Item and AttributeValue objects.

Method Summary

Modifier and Type	Method and Description
static void	checkInvalidAttribute(String attrName, Object val)
static void	checkInvalidAttrName(String attrName)
static Map<String,AttributeValue>	fromSimpleMap(Map<String,Object> map) Converts a map of string to simple objects into the low-level representation; or null if the input is null.
static Integer	minimum(Integer one, Integer two) Returns the minimum of the two input integers taking null into account.
static Map<String,Condition>	toAttributeConditionMap(Collection<? extends Filter<?>> filters) Returns the low level representation of a collection of Filter.
static AttributeValue	toAttributeValue(Object value) Converts a simple value into the low-level representation.
static Map<String,AttributeValue>	toAttributeValueMap(Collection<KeyAttribute> primaryKey) Converts the specified primary key into the low-level representation.
static Map<String,AttributeValue>	toAttributeValueMap(KeyAttribute... primaryKey) Converts the specified primary key into the low-level representation.
static Map<String,AttributeValue>	toAttributeValueMap(PrimaryKey primaryKey) Converts the specified primary key into the low-level representation.
static Map<String,AttributeValue>	toAttributeValues(Item item) Converts an Item into the low-level representation; or null if the input is null.
static AttributeValue[]	toAttributeValues(Object[] values) Converts the input array of values into an array of low level representation of those values.
static Map<String,AttributeValueUpdate>	toAttributeValueUpdate(List<AttributeUpdate> attributesToUpdate) Converts a list of AttributeUpdate into the low-level representation; or null if the input is null.
static BigDecimal	toBigDecimal(Number n) Converts a number into BigDecimal representation.
static Set<BigDecimal>	toBigDecimalSet(Number... val)
static Set<BigDecimal>	toBigDecimalSet(Set<Number> vals)
static Map<String,ExpectedAttributeValue>	toExpectedAttributeValueMap(Collection<Expected> expectedSet) Returns the low level representation of a collection of Expected.
static Item	toItem(Map<String,AttributeValue> item) Returns an Item given the low level item information; or null if the input is null;
static List<Item>	toItemList(List<Map<String,AttributeValue>> items) Returns a non-null list of Item's given the low level list of item information.
static List<Object>	toSimpleList(List<AttributeValue> attrValues) Converts a list of low-level AttributeValue into a list of simple values.
static <T> List<T>	toSimpleListValue(List<AttributeValue> values) Convenient method to convert a list of low-level AttributeValue into a list of values of the same type T.
static <T> Map<String,T>	toSimpleMapValue(Map<String,AttributeValue> values)
static <T> T	toSimpleValue(AttributeValue value) Converts a low-level AttributeValue into a simple value, which can be one of the followings: String Set<String> Number (including any subtypes and primitive types) Set<Number> byte[] Set<byte[]> ByteBuffer Set<ByteBuffer> Boolean or boolean null Map<String,T>, where T can be any type on this list but must not induce any circular reference List<T>, where T can be any type on this list but must not induce any circular reference
static String	valToString(Object val) Returns the string representation of the given value; or null if the value is null.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

toItem

public static Item toItem(Map<String,AttributeValue> item)

Returns an Item given the low level item information; or null if the input is null;

toItemList

public static List<Item> toItemList(List<Map<String,AttributeValue>> items)

Returns a non-null list of Item's given the low level list of item information.

toAttributeValues

public static Map<String,AttributeValue> toAttributeValues(Item item)

Converts an Item into the low-level representation; or null if the input is null.

fromSimpleMap

public static Map<String,AttributeValue> fromSimpleMap(Map<String,Object> map)

Converts a map of string to simple objects into the low-level representation; or null if the input is null.

toAttributeValueUpdate

public static Map<String,AttributeValueUpdate> toAttributeValueUpdate(List<AttributeUpdate> attributesToUpdate)

Converts a list of AttributeUpdate into the low-level representation; or null if the input is null.

toAttributeValue

public static AttributeValue toAttributeValue(Object value)

Converts a simple value into the low-level representation.

Parameters:

value - the given value which can be one of the followings:

• String
• Set<String>
• Number (including any subtypes and primitive types)
• Set<Number>
• byte[]
• Set<byte[]>
• ByteBuffer
• Set<ByteBuffer>
• Boolean or boolean
• null
• Map<String,T>, where T can be any type on this list but must not induce any circular reference
• List<T>, where T can be any type on this list but must not induce any circular reference

Returns:

a non-null low level representation of the input object value

Throws:

UnsupportedOperationException - if the input object type is not supported

toSimpleList

public static List<Object> toSimpleList(List<AttributeValue> attrValues)

Converts a list of low-level AttributeValue into a list of simple values. Each value in the returned list can be one of the followings:

• String
• Set<String>
• Number (including any subtypes and primitive types)
• Set<Number>
• byte[]
• Set<byte[]>
• ByteBuffer
• Set<ByteBuffer>
• Boolean or boolean
• null
• Map<String,T>, where T can be any type on this list but must not induce any circular reference
• List<T>, where T can be any type on this list but must not induce any circular reference

toSimpleListValue

public static <T> List<T> toSimpleListValue(List<AttributeValue> values)

Convenient method to convert a list of low-level AttributeValue into a list of values of the same type T. Each value in the returned list can be one of the followings:

• String
• Set<String>
• Number (including any subtypes and primitive types)
• Set<Number>
• byte[]
• Set<byte[]>
• ByteBuffer
• Set<ByteBuffer>
• Boolean or boolean
• null
• Map<String,T>, where T can be any type on this list but must not induce any circular reference
• List<T>, where T can be any type on this list but must not induce any circular reference

toSimpleMapValue

public static <T> Map<String,T> toSimpleMapValue(Map<String,AttributeValue> values)

valToString

public static String valToString(Object val)

Returns the string representation of the given value; or null if the value is null. For BigDecimal it will be the string representation without an exponent field.

toSimpleValue

public static <T> T toSimpleValue(AttributeValue value)

Converts a low-level AttributeValue into a simple value, which can be one of the followings:

• String
• Set<String>
• Number (including any subtypes and primitive types)
• Set<Number>
• byte[]
• Set<byte[]>
• ByteBuffer
• Set<ByteBuffer>
• Boolean or boolean
• null
• Map<String,T>, where T can be any type on this list but must not induce any circular reference
• List<T>, where T can be any type on this list but must not induce any circular reference

Throws:

IllegalArgumentException - if an empty AttributeValue value is specified

minimum

public static Integer minimum(Integer one,
                              Integer two)

Returns the minimum of the two input integers taking null into account. Returns null if both integers are null. Otherwise, a null Integer is treated as infinity.

toExpectedAttributeValueMap

public static Map<String,ExpectedAttributeValue> toExpectedAttributeValueMap(Collection<Expected> expectedSet)

Returns the low level representation of a collection of Expected.

toAttributeConditionMap

public static Map<String,Condition> toAttributeConditionMap(Collection<? extends Filter<?>> filters)

Returns the low level representation of a collection of Filter.

toAttributeValues

public static AttributeValue[] toAttributeValues(Object[] values)

Converts the input array of values into an array of low level representation of those values. A value in the input array can be one of the followings:

• String
• Set<String>
• Number (including any subtypes and primitive types)
• Set<Number>
• byte[]
• Set<byte[]>
• ByteBuffer
• Set<ByteBuffer>
• Boolean or boolean
• null
• Map<String,T>, where T can be any type on this list but must not induce any circular reference
• List<T>, where T can be any type on this list but must not induce any circular reference

toAttributeValueMap

public static Map<String,AttributeValue> toAttributeValueMap(Collection<KeyAttribute> primaryKey)

Converts the specified primary key into the low-level representation.

toAttributeValueMap

public static Map<String,AttributeValue> toAttributeValueMap(PrimaryKey primaryKey)

Converts the specified primary key into the low-level representation.

toAttributeValueMap

public static Map<String,AttributeValue> toAttributeValueMap(KeyAttribute... primaryKey)

Converts the specified primary key into the low-level representation.

toBigDecimal

public static BigDecimal toBigDecimal(Number n)

Converts a number into BigDecimal representation.

toBigDecimalSet

public static Set<BigDecimal> toBigDecimalSet(Number... val)

toBigDecimalSet

public static Set<BigDecimal> toBigDecimalSet(Set<Number> vals)

checkInvalidAttrName

public static void checkInvalidAttrName(String attrName)

checkInvalidAttribute

public static void checkInvalidAttribute(String attrName,
                                         Object val)