@Generated(value="software.amazon.awssdk:codegen") public final class ExpectedAttributeValue extends Object implements StructuredPojo, 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 | 
exists()
 Causes DynamoDB to evaluate the value before attempting a conditional operation: 
 | 
<T> Optional<T> | 
getValueForField(String fieldName,
                Class<T> clazz)  | 
int | 
hashCode()  | 
void | 
marshall(ProtocolMarshaller protocolMarshaller)
Marshalls this structured data using the given  
ProtocolMarshaller. | 
static Class<? extends ExpectedAttributeValue.Builder> | 
serializableBuilderClass()  | 
ExpectedAttributeValue.Builder | 
toBuilder()
Take this object and create a builder that contains all of the current property values of this object. 
 | 
String | 
toString()  | 
AttributeValue | 
value()
 Represents the data for the expected attribute. 
 | 
copypublic 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 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
 ConditionalCheckFailedException.
 
 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
 ConditionalCheckFailedException.
 
 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 ConditionalCheckFailedException.
         
         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
         ConditionalCheckFailedException.
         
         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 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"]}
         
ComparisonOperatorpublic 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"]}
         
ComparisonOperatorpublic 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.
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()
ToCopyableBuildertoBuilder in interface ToCopyableBuilder<ExpectedAttributeValue.Builder,ExpectedAttributeValue>public static ExpectedAttributeValue.Builder builder()
public static Class<? extends ExpectedAttributeValue.Builder> serializableBuilderClass()
public void marshall(ProtocolMarshaller protocolMarshaller)
StructuredPojoProtocolMarshaller.marshall in interface StructuredPojoprotocolMarshaller - Implementation of ProtocolMarshaller used to marshall this object's data.Copyright © 2017 Amazon Web Services, Inc. All Rights Reserved.