@Generated(value="software.amazon.awssdk:codegen") public final class ExpectedAttributeValue extends Object implements SdkPojo, Serializable, ToCopyableBuilder<ExpectedAttributeValue.Builder,ExpectedAttributeValue>
Represents a condition to be compared with an attribute value. This condition can be used with
DeleteItem
, PutItem
, or UpdateItem
operations; if the comparison evaluates to
true, the operation succeeds; if not, the operation fails. You can use ExpectedAttributeValue
in one of
two different ways:
Use AttributeValueList
to specify one or more values to compare against an attribute. Use
ComparisonOperator
to specify how you want to perform the comparison. If the comparison evaluates to
true, then the conditional operation succeeds.
Use Value
to specify a value that DynamoDB will compare against an attribute. If the values match, then
ExpectedAttributeValue
evaluates to true and the conditional operation succeeds. Optionally, you can
also set Exists
to false, indicating that you do not expect to find the attribute value in the
table. In this case, the conditional operation succeeds only if the comparison evaluates to false.
Value
and Exists
are incompatible with AttributeValueList
and
ComparisonOperator
. Note that if you use both sets of parameters at once, DynamoDB will return a
ValidationException
exception.
Modifier and Type | Class and Description |
---|---|
static interface |
ExpectedAttributeValue.Builder |
Modifier and Type | Method and Description |
---|---|
List<AttributeValue> |
attributeValueList()
One or more values to evaluate against the supplied attribute.
|
static ExpectedAttributeValue.Builder |
builder() |
ComparisonOperator |
comparisonOperator()
A comparator for evaluating attributes in the
AttributeValueList . |
String |
comparisonOperatorAsString()
A comparator for evaluating attributes in the
AttributeValueList . |
boolean |
equals(Object obj) |
boolean |
equalsBySdkFields(Object obj) |
Boolean |
exists()
Causes DynamoDB to evaluate the value before attempting a conditional operation:
|
<T> Optional<T> |
getValueForField(String fieldName,
Class<T> clazz) |
boolean |
hasAttributeValueList()
Returns true if the AttributeValueList property was specified by the sender (it may be empty), or false if the
sender did not specify the value (it will be empty).
|
int |
hashCode() |
List<SdkField<?>> |
sdkFields() |
static Class<? extends ExpectedAttributeValue.Builder> |
serializableBuilderClass() |
ExpectedAttributeValue.Builder |
toBuilder() |
String |
toString()
Returns a string representation of this object.
|
AttributeValue |
value()
Represents the data for the expected attribute.
|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
copy
public final AttributeValue value()
Represents the data for the expected attribute.
Each attribute value is described as a name-value pair. The name is the data type, and the value is the data itself.
For more information, see Data Types in the Amazon DynamoDB Developer Guide.
Each attribute value is described as a name-value pair. The name is the data type, and the value is the data itself.
For more information, see Data Types in the Amazon DynamoDB Developer Guide.
public final Boolean exists()
Causes DynamoDB to evaluate the value before attempting a conditional operation:
If Exists
is true
, DynamoDB will check to see if that attribute value already exists in
the table. If it is found, then the operation succeeds. If it is not found, the operation fails with a
ConditionCheckFailedException
.
If Exists
is false
, DynamoDB assumes that the attribute value does not exist in the
table. If in fact the value does not exist, then the assumption is valid and the operation succeeds. If the value
is found, despite the assumption that it does not exist, the operation fails with a
ConditionCheckFailedException
.
The default setting for Exists
is true
. If you supply a Value
all by
itself, DynamoDB assumes the attribute exists: You don't have to set Exists
to true
,
because it is implied.
DynamoDB returns a ValidationException
if:
Exists
is true
but there is no Value
to check. (You expect a value to
exist, but don't specify what that value is.)
Exists
is false
but you also provide a Value
. (You cannot expect an
attribute to have a value, while also expecting it not to exist.)
If Exists
is true
, DynamoDB will check to see if that attribute value already
exists in the table. If it is found, then the operation succeeds. If it is not found, the operation fails
with a ConditionCheckFailedException
.
If Exists
is false
, DynamoDB assumes that the attribute value does not exist in
the table. If in fact the value does not exist, then the assumption is valid and the operation succeeds.
If the value is found, despite the assumption that it does not exist, the operation fails with a
ConditionCheckFailedException
.
The default setting for Exists
is true
. If you supply a Value
all
by itself, DynamoDB assumes the attribute exists: You don't have to set Exists
to
true
, because it is implied.
DynamoDB returns a ValidationException
if:
Exists
is true
but there is no Value
to check. (You expect a value
to exist, but don't specify what that value is.)
Exists
is false
but you also provide a Value
. (You cannot expect
an attribute to have a value, while also expecting it not to exist.)
public final ComparisonOperator comparisonOperator()
A comparator for evaluating attributes in the AttributeValueList
. For example, equals, greater than,
less than, etc.
The following comparison operators are available:
EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH | IN | BETWEEN
The following are descriptions of each comparison operator.
EQ
: Equal. EQ
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
Binary, String Set, Number Set, or Binary Set. If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not equal
{"NS":["6", "2", "1"]}
.
NE
: Not equal. NE
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
of type String, Number, Binary,
String Set, Number Set, or Binary Set. If an item contains an AttributeValue
of a different type
than the one provided in the request, the value does not match. For example, {"S":"6"}
does not
equal {"N":"6"}
. Also, {"N":"6"}
does not equal {"NS":["6", "2", "1"]}
.
LE
: Less than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different type than
the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
LT
: Less than.
AttributeValueList
can contain only one AttributeValue
of type String, Number, or
Binary (not a set type). If an item contains an AttributeValue
element of a different type than the
one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
GE
: Greater than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different type than
the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
GT
: Greater than.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different type than
the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
NOT_NULL
: The attribute exists. NOT_NULL
is supported for all data types, including
lists and maps.
This operator tests for the existence of an attribute, not its data type. If the data type of attribute "
a
" is null, and you evaluate it using NOT_NULL
, the result is a Boolean
true
. This result is because the attribute "a
" exists; its data type is not relevant to
the NOT_NULL
comparison operator.
NULL
: The attribute does not exist. NULL
is supported for all data types, including
lists and maps.
This operator tests for the nonexistence of an attribute, not its data type. If the data type of attribute "
a
" is null, and you evaluate it using NULL
, the result is a Boolean false
.
This is because the attribute "a
" exists; its data type is not relevant to the NULL
comparison operator.
CONTAINS
: Checks for a subsequence, or value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If the target attribute of the comparison is of type String, then the operator checks
for a substring match. If the target attribute of the comparison is of type Binary, then the operator looks for a
subsequence of the target that matches the input. If the target attribute of the comparison is a set ("
SS
", "NS
", or "BS
"), then the operator evaluates to true if it finds an
exact match with any member of the set.
CONTAINS is supported for lists: When evaluating "a CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
NOT_CONTAINS
: Checks for absence of a subsequence, or absence of a value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If the target attribute of the comparison is a String, then the operator checks for
the absence of a substring match. If the target attribute of the comparison is Binary, then the operator checks
for the absence of a subsequence of the target that matches the input. If the target attribute of the comparison
is a set ("SS
", "NS
", or "BS
"), then the operator evaluates to true if it
does not find an exact match with any member of the set.
NOT_CONTAINS is supported for lists: When evaluating "a NOT CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
BEGINS_WITH
: Checks for a prefix.
AttributeValueList
can contain only one AttributeValue
of type String or Binary (not a
Number or a set type). The target attribute of the comparison must be of type String or Binary (not a Number or a
set type).
IN
: Checks for matching elements in a list.
AttributeValueList
can contain one or more AttributeValue
elements of type String,
Number, or Binary. These attributes are compared against an existing attribute of an item. If any elements of the
input are equal to the item attribute, the expression evaluates to true.
BETWEEN
: Greater than or equal to the first value, and less than or equal to the second value.
AttributeValueList
must contain two AttributeValue
elements of the same type, either
String, Number, or Binary (not a set type). A target attribute matches if the target value is greater than, or
equal to, the first element and less than, or equal to, the second element. If an item contains an
AttributeValue
element of a different type than the one provided in the request, the value does not
match. For example, {"S":"6"}
does not compare to {"N":"6"}
. Also,
{"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
If the service returns an enum value that is not available in the current SDK version,
comparisonOperator
will return ComparisonOperator.UNKNOWN_TO_SDK_VERSION
. The raw value returned
by the service is available from comparisonOperatorAsString()
.
AttributeValueList
. For example, equals,
greater than, less than, etc.
The following comparison operators are available:
EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH | IN | BETWEEN
The following are descriptions of each comparison operator.
EQ
: Equal. EQ
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, Binary, String Set, Number Set, or Binary Set. If an item contains an AttributeValue
element of a different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not equal
{"NS":["6", "2", "1"]}
.
NE
: Not equal. NE
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
of type String, Number,
Binary, String Set, Number Set, or Binary Set. If an item contains an AttributeValue
of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not equal
{"NS":["6", "2", "1"]}
.
LE
: Less than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not
compare to {"NS":["6", "2", "1"]}
.
LT
: Less than.
AttributeValueList
can contain only one AttributeValue
of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different
type than the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not compare to
{"NS":["6", "2", "1"]}
.
GE
: Greater than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not
compare to {"NS":["6", "2", "1"]}
.
GT
: Greater than.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not
compare to {"NS":["6", "2", "1"]}
.
NOT_NULL
: The attribute exists. NOT_NULL
is supported for all data types,
including lists and maps.
This operator tests for the existence of an attribute, not its data type. If the data type of attribute "
a
" is null, and you evaluate it using NOT_NULL
, the result is a Boolean
true
. This result is because the attribute "a
" exists; its data type is not
relevant to the NOT_NULL
comparison operator.
NULL
: The attribute does not exist. NULL
is supported for all data types,
including lists and maps.
This operator tests for the nonexistence of an attribute, not its data type. If the data type of
attribute "a
" is null, and you evaluate it using NULL
, the result is a Boolean
false
. This is because the attribute "a
" exists; its data type is not relevant
to the NULL
comparison operator.
CONTAINS
: Checks for a subsequence, or value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If the target attribute of the comparison is of type String, then the
operator checks for a substring match. If the target attribute of the comparison is of type Binary, then
the operator looks for a subsequence of the target that matches the input. If the target attribute of the
comparison is a set ("SS
", "NS
", or "BS
"), then the operator
evaluates to true if it finds an exact match with any member of the set.
CONTAINS is supported for lists: When evaluating "a CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
NOT_CONTAINS
: Checks for absence of a subsequence, or absence of a value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If the target attribute of the comparison is a String, then the
operator checks for the absence of a substring match. If the target attribute of the comparison is
Binary, then the operator checks for the absence of a subsequence of the target that matches the input.
If the target attribute of the comparison is a set ("SS
", "NS
", or "
BS
"), then the operator evaluates to true if it does not find an exact match with any
member of the set.
NOT_CONTAINS is supported for lists: When evaluating "a NOT CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
BEGINS_WITH
: Checks for a prefix.
AttributeValueList
can contain only one AttributeValue
of type String or Binary
(not a Number or a set type). The target attribute of the comparison must be of type String or Binary
(not a Number or a set type).
IN
: Checks for matching elements in a list.
AttributeValueList
can contain one or more AttributeValue
elements of type
String, Number, or Binary. These attributes are compared against an existing attribute of an item. If any
elements of the input are equal to the item attribute, the expression evaluates to true.
BETWEEN
: Greater than or equal to the first value, and less than or equal to the second
value.
AttributeValueList
must contain two AttributeValue
elements of the same type,
either String, Number, or Binary (not a set type). A target attribute matches if the target value is
greater than, or equal to, the first element and less than, or equal to, the second element. If an item
contains an AttributeValue
element of a different type than the one provided in the request,
the value does not match. For example, {"S":"6"}
does not compare to {"N":"6"}
.
Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
ComparisonOperator
public final String comparisonOperatorAsString()
A comparator for evaluating attributes in the AttributeValueList
. For example, equals, greater than,
less than, etc.
The following comparison operators are available:
EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH | IN | BETWEEN
The following are descriptions of each comparison operator.
EQ
: Equal. EQ
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
Binary, String Set, Number Set, or Binary Set. If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not equal
{"NS":["6", "2", "1"]}
.
NE
: Not equal. NE
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
of type String, Number, Binary,
String Set, Number Set, or Binary Set. If an item contains an AttributeValue
of a different type
than the one provided in the request, the value does not match. For example, {"S":"6"}
does not
equal {"N":"6"}
. Also, {"N":"6"}
does not equal {"NS":["6", "2", "1"]}
.
LE
: Less than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different type than
the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
LT
: Less than.
AttributeValueList
can contain only one AttributeValue
of type String, Number, or
Binary (not a set type). If an item contains an AttributeValue
element of a different type than the
one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
GE
: Greater than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different type than
the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
GT
: Greater than.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different type than
the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal
{"N":"6"}
. Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
.
NOT_NULL
: The attribute exists. NOT_NULL
is supported for all data types, including
lists and maps.
This operator tests for the existence of an attribute, not its data type. If the data type of attribute "
a
" is null, and you evaluate it using NOT_NULL
, the result is a Boolean
true
. This result is because the attribute "a
" exists; its data type is not relevant to
the NOT_NULL
comparison operator.
NULL
: The attribute does not exist. NULL
is supported for all data types, including
lists and maps.
This operator tests for the nonexistence of an attribute, not its data type. If the data type of attribute "
a
" is null, and you evaluate it using NULL
, the result is a Boolean false
.
This is because the attribute "a
" exists; its data type is not relevant to the NULL
comparison operator.
CONTAINS
: Checks for a subsequence, or value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If the target attribute of the comparison is of type String, then the operator checks
for a substring match. If the target attribute of the comparison is of type Binary, then the operator looks for a
subsequence of the target that matches the input. If the target attribute of the comparison is a set ("
SS
", "NS
", or "BS
"), then the operator evaluates to true if it finds an
exact match with any member of the set.
CONTAINS is supported for lists: When evaluating "a CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
NOT_CONTAINS
: Checks for absence of a subsequence, or absence of a value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String, Number,
or Binary (not a set type). If the target attribute of the comparison is a String, then the operator checks for
the absence of a substring match. If the target attribute of the comparison is Binary, then the operator checks
for the absence of a subsequence of the target that matches the input. If the target attribute of the comparison
is a set ("SS
", "NS
", or "BS
"), then the operator evaluates to true if it
does not find an exact match with any member of the set.
NOT_CONTAINS is supported for lists: When evaluating "a NOT CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
BEGINS_WITH
: Checks for a prefix.
AttributeValueList
can contain only one AttributeValue
of type String or Binary (not a
Number or a set type). The target attribute of the comparison must be of type String or Binary (not a Number or a
set type).
IN
: Checks for matching elements in a list.
AttributeValueList
can contain one or more AttributeValue
elements of type String,
Number, or Binary. These attributes are compared against an existing attribute of an item. If any elements of the
input are equal to the item attribute, the expression evaluates to true.
BETWEEN
: Greater than or equal to the first value, and less than or equal to the second value.
AttributeValueList
must contain two AttributeValue
elements of the same type, either
String, Number, or Binary (not a set type). A target attribute matches if the target value is greater than, or
equal to, the first element and less than, or equal to, the second element. If an item contains an
AttributeValue
element of a different type than the one provided in the request, the value does not
match. For example, {"S":"6"}
does not compare to {"N":"6"}
. Also,
{"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
If the service returns an enum value that is not available in the current SDK version,
comparisonOperator
will return ComparisonOperator.UNKNOWN_TO_SDK_VERSION
. The raw value returned
by the service is available from comparisonOperatorAsString()
.
AttributeValueList
. For example, equals,
greater than, less than, etc.
The following comparison operators are available:
EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH | IN | BETWEEN
The following are descriptions of each comparison operator.
EQ
: Equal. EQ
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, Binary, String Set, Number Set, or Binary Set. If an item contains an AttributeValue
element of a different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not equal
{"NS":["6", "2", "1"]}
.
NE
: Not equal. NE
is supported for all data types, including lists and maps.
AttributeValueList
can contain only one AttributeValue
of type String, Number,
Binary, String Set, Number Set, or Binary Set. If an item contains an AttributeValue
of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not equal
{"NS":["6", "2", "1"]}
.
LE
: Less than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not
compare to {"NS":["6", "2", "1"]}
.
LT
: Less than.
AttributeValueList
can contain only one AttributeValue
of type String, Number,
or Binary (not a set type). If an item contains an AttributeValue
element of a different
type than the one provided in the request, the value does not match. For example, {"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not compare to
{"NS":["6", "2", "1"]}
.
GE
: Greater than or equal.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not
compare to {"NS":["6", "2", "1"]}
.
GT
: Greater than.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If an item contains an AttributeValue
element of a
different type than the one provided in the request, the value does not match. For example,
{"S":"6"}
does not equal {"N":"6"}
. Also, {"N":"6"}
does not
compare to {"NS":["6", "2", "1"]}
.
NOT_NULL
: The attribute exists. NOT_NULL
is supported for all data types,
including lists and maps.
This operator tests for the existence of an attribute, not its data type. If the data type of attribute "
a
" is null, and you evaluate it using NOT_NULL
, the result is a Boolean
true
. This result is because the attribute "a
" exists; its data type is not
relevant to the NOT_NULL
comparison operator.
NULL
: The attribute does not exist. NULL
is supported for all data types,
including lists and maps.
This operator tests for the nonexistence of an attribute, not its data type. If the data type of
attribute "a
" is null, and you evaluate it using NULL
, the result is a Boolean
false
. This is because the attribute "a
" exists; its data type is not relevant
to the NULL
comparison operator.
CONTAINS
: Checks for a subsequence, or value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If the target attribute of the comparison is of type String, then the
operator checks for a substring match. If the target attribute of the comparison is of type Binary, then
the operator looks for a subsequence of the target that matches the input. If the target attribute of the
comparison is a set ("SS
", "NS
", or "BS
"), then the operator
evaluates to true if it finds an exact match with any member of the set.
CONTAINS is supported for lists: When evaluating "a CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
NOT_CONTAINS
: Checks for absence of a subsequence, or absence of a value in a set.
AttributeValueList
can contain only one AttributeValue
element of type String,
Number, or Binary (not a set type). If the target attribute of the comparison is a String, then the
operator checks for the absence of a substring match. If the target attribute of the comparison is
Binary, then the operator checks for the absence of a subsequence of the target that matches the input.
If the target attribute of the comparison is a set ("SS
", "NS
", or "
BS
"), then the operator evaluates to true if it does not find an exact match with any
member of the set.
NOT_CONTAINS is supported for lists: When evaluating "a NOT CONTAINS b
", "a
" can be a list; however, "b
" cannot be a set, a map, or a list.
BEGINS_WITH
: Checks for a prefix.
AttributeValueList
can contain only one AttributeValue
of type String or Binary
(not a Number or a set type). The target attribute of the comparison must be of type String or Binary
(not a Number or a set type).
IN
: Checks for matching elements in a list.
AttributeValueList
can contain one or more AttributeValue
elements of type
String, Number, or Binary. These attributes are compared against an existing attribute of an item. If any
elements of the input are equal to the item attribute, the expression evaluates to true.
BETWEEN
: Greater than or equal to the first value, and less than or equal to the second
value.
AttributeValueList
must contain two AttributeValue
elements of the same type,
either String, Number, or Binary (not a set type). A target attribute matches if the target value is
greater than, or equal to, the first element and less than, or equal to, the second element. If an item
contains an AttributeValue
element of a different type than the one provided in the request,
the value does not match. For example, {"S":"6"}
does not compare to {"N":"6"}
.
Also, {"N":"6"}
does not compare to {"NS":["6", "2", "1"]}
ComparisonOperator
public final boolean hasAttributeValueList()
public final List<AttributeValue> attributeValueList()
One or more values to evaluate against the supplied attribute. The number of values in the list depends on the
ComparisonOperator
being used.
For type Number, value comparisons are numeric.
String value comparisons for greater than, equals, or less than are based on ASCII character code values. For
example, a
is greater than A
, and a
is greater than B
. For a
list of code values, see http://en.wikipedia
.org/wiki/ASCII#ASCII_printable_characters.
For Binary, DynamoDB treats each byte of the binary data as unsigned when it compares binary values.
For information on specifying data types in JSON, see JSON Data Format in the Amazon DynamoDB Developer Guide.
Attempts to modify the collection returned by this method will result in an UnsupportedOperationException.
You can use hasAttributeValueList()
to see if a value was sent in this field.
ComparisonOperator
being used.
For type Number, value comparisons are numeric.
String value comparisons for greater than, equals, or less than are based on ASCII character code values.
For example, a
is greater than A
, and a
is greater than
B
. For a list of code values, see http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters.
For Binary, DynamoDB treats each byte of the binary data as unsigned when it compares binary values.
For information on specifying data types in JSON, see JSON Data Format in the Amazon DynamoDB Developer Guide.
public ExpectedAttributeValue.Builder toBuilder()
toBuilder
in interface ToCopyableBuilder<ExpectedAttributeValue.Builder,ExpectedAttributeValue>
public static ExpectedAttributeValue.Builder builder()
public static Class<? extends ExpectedAttributeValue.Builder> serializableBuilderClass()
public final boolean equalsBySdkFields(Object obj)
equalsBySdkFields
in interface SdkPojo
public final String toString()
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