public class KeysAndAttributes
extends java.lang.Object
implements java.io.Serializable
Represents a set of primary keys and, for each key, the attributes to retrieve from the table.
For each primary key, you must provide all of the key attributes. For example, with a simple primary key, you only need to provide the partition key. For a composite primary key, you must provide both the partition key and the sort key.
Constructor and Description |
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KeysAndAttributes() |
Modifier and Type | Method and Description |
---|---|
KeysAndAttributes |
addExpressionAttributeNamesEntry(java.lang.String key,
java.lang.String value)
One or more substitution tokens for attribute names in an expression.
|
KeysAndAttributes |
clearExpressionAttributeNamesEntries()
Removes all the entries added into ExpressionAttributeNames.
|
boolean |
equals(java.lang.Object obj) |
java.util.List<java.lang.String> |
getAttributesToGet()
This is a legacy parameter.
|
java.lang.Boolean |
getConsistentRead()
The consistency of a read operation.
|
java.util.Map<java.lang.String,java.lang.String> |
getExpressionAttributeNames()
One or more substitution tokens for attribute names in an expression.
|
java.util.List<java.util.Map<java.lang.String,AttributeValue>> |
getKeys()
The primary key attribute values that define the items and the attributes
associated with the items.
|
java.lang.String |
getProjectionExpression()
A string that identifies one or more attributes to retrieve from the
table.
|
int |
hashCode() |
java.lang.Boolean |
isConsistentRead()
The consistency of a read operation.
|
void |
setAttributesToGet(java.util.Collection<java.lang.String> attributesToGet)
This is a legacy parameter.
|
void |
setConsistentRead(java.lang.Boolean consistentRead)
The consistency of a read operation.
|
void |
setExpressionAttributeNames(java.util.Map<java.lang.String,java.lang.String> expressionAttributeNames)
One or more substitution tokens for attribute names in an expression.
|
void |
setKeys(java.util.Collection<java.util.Map<java.lang.String,AttributeValue>> keys)
The primary key attribute values that define the items and the attributes
associated with the items.
|
void |
setProjectionExpression(java.lang.String projectionExpression)
A string that identifies one or more attributes to retrieve from the
table.
|
java.lang.String |
toString()
Returns a string representation of this object; useful for testing and
debugging.
|
KeysAndAttributes |
withAttributesToGet(java.util.Collection<java.lang.String> attributesToGet)
This is a legacy parameter.
|
KeysAndAttributes |
withAttributesToGet(java.lang.String... attributesToGet)
This is a legacy parameter.
|
KeysAndAttributes |
withConsistentRead(java.lang.Boolean consistentRead)
The consistency of a read operation.
|
KeysAndAttributes |
withExpressionAttributeNames(java.util.Map<java.lang.String,java.lang.String> expressionAttributeNames)
One or more substitution tokens for attribute names in an expression.
|
KeysAndAttributes |
withKeys(java.util.Collection<java.util.Map<java.lang.String,AttributeValue>> keys)
The primary key attribute values that define the items and the attributes
associated with the items.
|
KeysAndAttributes |
withKeys(java.util.Map<java.lang.String,AttributeValue>... keys)
The primary key attribute values that define the items and the attributes
associated with the items.
|
KeysAndAttributes |
withProjectionExpression(java.lang.String projectionExpression)
A string that identifies one or more attributes to retrieve from the
table.
|
public java.util.List<java.util.Map<java.lang.String,AttributeValue>> getKeys()
The primary key attribute values that define the items and the attributes associated with the items.
The primary key attribute values that define the items and the attributes associated with the items.
public void setKeys(java.util.Collection<java.util.Map<java.lang.String,AttributeValue>> keys)
The primary key attribute values that define the items and the attributes associated with the items.
keys
- The primary key attribute values that define the items and the attributes associated with the items.
public KeysAndAttributes withKeys(java.util.Map<java.lang.String,AttributeValue>... keys)
The primary key attribute values that define the items and the attributes associated with the items.
Returns a reference to this object so that method calls can be chained together.
keys
- The primary key attribute values that define the items and the attributes associated with the items.
public KeysAndAttributes withKeys(java.util.Collection<java.util.Map<java.lang.String,AttributeValue>> keys)
The primary key attribute values that define the items and the attributes associated with the items.
Returns a reference to this object so that method calls can be chained together.
keys
- The primary key attribute values that define the items and the attributes associated with the items.
public java.util.List<java.lang.String> getAttributesToGet()
This is a legacy parameter. Use ProjectionExpression
instead. For more information, see Legacy Conditional Parameters in the Amazon DynamoDB Developer
Guide.
This is a legacy parameter. Use ProjectionExpression
instead. For more information, see Legacy Conditional Parameters in the Amazon DynamoDB
Developer Guide.
public void setAttributesToGet(java.util.Collection<java.lang.String> attributesToGet)
This is a legacy parameter. Use ProjectionExpression
instead. For more information, see Legacy Conditional Parameters in the Amazon DynamoDB Developer
Guide.
attributesToGet
-
This is a legacy parameter. Use
ProjectionExpression
instead. For more
information, see Legacy Conditional Parameters in the Amazon DynamoDB
Developer Guide.
public KeysAndAttributes withAttributesToGet(java.lang.String... attributesToGet)
This is a legacy parameter. Use ProjectionExpression
instead. For more information, see Legacy Conditional Parameters in the Amazon DynamoDB Developer
Guide.
Returns a reference to this object so that method calls can be chained together.
attributesToGet
-
This is a legacy parameter. Use
ProjectionExpression
instead. For more
information, see Legacy Conditional Parameters in the Amazon DynamoDB
Developer Guide.
public KeysAndAttributes withAttributesToGet(java.util.Collection<java.lang.String> attributesToGet)
This is a legacy parameter. Use ProjectionExpression
instead. For more information, see Legacy Conditional Parameters in the Amazon DynamoDB Developer
Guide.
Returns a reference to this object so that method calls can be chained together.
attributesToGet
-
This is a legacy parameter. Use
ProjectionExpression
instead. For more
information, see Legacy Conditional Parameters in the Amazon DynamoDB
Developer Guide.
public java.lang.Boolean isConsistentRead()
The consistency of a read operation. If set to true
, then a
strongly consistent read is used; otherwise, an eventually consistent
read is used.
The consistency of a read operation. If set to true
,
then a strongly consistent read is used; otherwise, an eventually
consistent read is used.
public java.lang.Boolean getConsistentRead()
The consistency of a read operation. If set to true
, then a
strongly consistent read is used; otherwise, an eventually consistent
read is used.
The consistency of a read operation. If set to true
,
then a strongly consistent read is used; otherwise, an eventually
consistent read is used.
public void setConsistentRead(java.lang.Boolean consistentRead)
The consistency of a read operation. If set to true
, then a
strongly consistent read is used; otherwise, an eventually consistent
read is used.
consistentRead
-
The consistency of a read operation. If set to
true
, then a strongly consistent read is used;
otherwise, an eventually consistent read is used.
public KeysAndAttributes withConsistentRead(java.lang.Boolean consistentRead)
The consistency of a read operation. If set to true
, then a
strongly consistent read is used; otherwise, an eventually consistent
read is used.
Returns a reference to this object so that method calls can be chained together.
consistentRead
-
The consistency of a read operation. If set to
true
, then a strongly consistent read is used;
otherwise, an eventually consistent read is used.
public java.lang.String getProjectionExpression()
A string that identifies one or more attributes to retrieve from the
table. These attributes can include scalars, sets, or elements of a JSON
document. The attributes in the ProjectionExpression
must be
separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
A string that identifies one or more attributes to retrieve from
the table. These attributes can include scalars, sets, or
elements of a JSON document. The attributes in the
ProjectionExpression
must be separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
public void setProjectionExpression(java.lang.String projectionExpression)
A string that identifies one or more attributes to retrieve from the
table. These attributes can include scalars, sets, or elements of a JSON
document. The attributes in the ProjectionExpression
must be
separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
projectionExpression
-
A string that identifies one or more attributes to retrieve
from the table. These attributes can include scalars, sets, or
elements of a JSON document. The attributes in the
ProjectionExpression
must be separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
public KeysAndAttributes withProjectionExpression(java.lang.String projectionExpression)
A string that identifies one or more attributes to retrieve from the
table. These attributes can include scalars, sets, or elements of a JSON
document. The attributes in the ProjectionExpression
must be
separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
Returns a reference to this object so that method calls can be chained together.
projectionExpression
-
A string that identifies one or more attributes to retrieve
from the table. These attributes can include scalars, sets, or
elements of a JSON document. The attributes in the
ProjectionExpression
must be separated by commas.
If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.
For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
public java.util.Map<java.lang.String,java.lang.String> getExpressionAttributeNames()
One or more substitution tokens for attribute names in an expression. The
following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so it cannot
be used directly in an expression. (For the complete list of reserved
words, see Reserved Words in the Amazon DynamoDB Developer Guide). To
work around this, you could specify the following for
ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
One or more substitution tokens for attribute names in an
expression. The following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so it
cannot be used directly in an expression. (For the complete list
of reserved words, see Reserved Words in the Amazon DynamoDB Developer
Guide). To work around this, you could specify the following
for ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
public void setExpressionAttributeNames(java.util.Map<java.lang.String,java.lang.String> expressionAttributeNames)
One or more substitution tokens for attribute names in an expression. The
following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so it cannot
be used directly in an expression. (For the complete list of reserved
words, see Reserved Words in the Amazon DynamoDB Developer Guide). To
work around this, you could specify the following for
ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
expressionAttributeNames
-
One or more substitution tokens for attribute names in an
expression. The following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so
it cannot be used directly in an expression. (For the complete
list of reserved words, see Reserved Words in the Amazon DynamoDB Developer
Guide). To work around this, you could specify the
following for ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
public KeysAndAttributes withExpressionAttributeNames(java.util.Map<java.lang.String,java.lang.String> expressionAttributeNames)
One or more substitution tokens for attribute names in an expression. The
following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so it cannot
be used directly in an expression. (For the complete list of reserved
words, see Reserved Words in the Amazon DynamoDB Developer Guide). To
work around this, you could specify the following for
ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
Returns a reference to this object so that method calls can be chained together.
expressionAttributeNames
-
One or more substitution tokens for attribute names in an
expression. The following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so
it cannot be used directly in an expression. (For the complete
list of reserved words, see Reserved Words in the Amazon DynamoDB Developer
Guide). To work around this, you could specify the
following for ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
public KeysAndAttributes addExpressionAttributeNamesEntry(java.lang.String key, java.lang.String value)
One or more substitution tokens for attribute names in an expression. The
following are some use cases for using
ExpressionAttributeNames
:
To access an attribute whose name conflicts with a DynamoDB reserved word.
To create a placeholder for repeating occurrences of an attribute name in an expression.
To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
Percentile
The name of this attribute conflicts with a reserved word, so it cannot
be used directly in an expression. (For the complete list of reserved
words, see Reserved Words in the Amazon DynamoDB Developer Guide). To
work around this, you could specify the following for
ExpressionAttributeNames
:
{"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
#P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.
For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
The method adds a new key-value pair into ExpressionAttributeNames parameter, and returns a reference to this object so that method calls can be chained together.
key
- The key of the entry to be added into
ExpressionAttributeNames.value
- The corresponding value of the entry to be added into
ExpressionAttributeNames.public KeysAndAttributes clearExpressionAttributeNamesEntries()
Returns a reference to this object so that method calls can be chained together.
public java.lang.String toString()
toString
in class java.lang.Object
Object.toString()
public int hashCode()
hashCode
in class java.lang.Object
public boolean equals(java.lang.Object obj)
equals
in class java.lang.Object
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