ConstantExpression

Overview

The ConstantExpression implements ConstantExpression and represents values in WhereExpressions.

For example, the following WHERE statement

SELECT * FROM Employees WHERE (Position = 'Sales Manager')

using ConstantExpression would look like this:

WhereExpression lResult;
lResult = new BinaryExpression(
              new FieldExpression("Position"),
              new ConstantExpression("Sales Manager", DataType.String),
              BinaryOperator.Equal),

Location

Reference: com.remobjects.dataabstract.jar
Package: com.remobjects.dataabstract.expressions
Ancestry: Object | WhereExpression | ParameterExpression | ConstantExpression

constructor

Creates an instance of ConstantExpression.

constructor

ConstantExpression()

constructor (String, DataType, Integer) (declared in ParameterExpression)

Creates a new instance of the ParameterExpression class with a specified name, type and size of the parameter.

constructor(aName: String; aType: DataType; aSize: Integer)

ConstantExpression(String aName, DataType aType, Integer aSize)

Parameters:

aName: The name of the parameter.
aType: The data type of the parameter.
aSize: The size of the parameter; used if applicable to the type.

constructor (Object)

Creates an instance of ConstantExpression with the given constant value.

constructor(aValue: Object)

ConstantExpression(Object aValue)

Parameters:

aValue: The value of the constant.

constructor (Object, DataType)

Creates an instance of ConstantExpression with the given value and data type.

constructor(aValue: Object; aType: DataType)

ConstantExpression(Object aValue, DataType aType)

Parameters:

aValue: The value of the constant.
aType: The type of the constant.

combine (WhereExpression, WhereExpression): WhereExpression (declared in WhereExpression)

Creates a new BinaryExpression from the given aLeft and aRight operands using BinaryOperator.

class method combine(aLeft: WhereExpression; aRight: WhereExpression): WhereExpression

static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight)

Parameters:

aLeft: The left operand to be combined.
aRight: The right operand to be combined.

combine (WhereExpression, WhereExpression, BinaryOperator): WhereExpression (declared in WhereExpression)

Creates a new BinaryExpression from the given aLeft and aRight operands using the given operator.

class method combine(aLeft: WhereExpression; aRight: WhereExpression; anOperator: BinaryOperator): WhereExpression

static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight, BinaryOperator anOperator)

Parameters:

aLeft: The left operand to be combined.
aRight: The right operand to be combined.
anOperator: The operator to be used in combining.

deserializeObject

Returns the object of the given type from the given provided string.

class method deserializeObject(aSource: String; aDataType: DataType): Object

static Object deserializeObject(String aSource, DataType aDataType)

Parameters:

aSource: The string to be converted.
aDataType: The target type of the result value.

fromString (declared in WhereExpression)

Creates a new WhereExpression from the specified string, which should contain XML node in the correct Dynamic Where XML Format.

class method fromString(anXml: String): WhereExpression

static WhereExpression fromString(String anXml)

Parameters:

anXml: The given XML string.

fromStringToSql (declared in WhereExpression)

A helper method to convert a XML string into SQL string.

class method fromStringToSql(anXml: String): String

static String fromStringToSql(String anXml)

Parameters:

anXml: The XML string to be converted.

fromXmlNode (declared in WhereExpression)

Creates a new WhereExpression from the given XML node, which should be in the correct Dynamic Where XML Format.

class method fromXmlNode(aNode: Node): WhereExpression

static WhereExpression fromXmlNode(Node aNode)

Parameters:

aNode: The XML node to be parsed.

Kind

property Kind: WhereKind read;

WhereKind Kind { __get; }

ParameterName (declared in ParameterExpression)

property ParameterName: String read write;

String ParameterName { __get; __set; }

parseExpression (declared in WhereExpression)

class method parseExpression(node: Node): WhereExpression

static WhereExpression parseExpression(Node node)

Parameters:

node:

readFromXml

Initializes the current ConstantExpression from the given XML node.

method readFromXml(aNode: Node)

void readFromXml(Node aNode)

Parameters:

aNode: The node that contains the serialized expression.

serializeObject

Returns a string representation of the given value in consideration of the specified type.

class method serializeObject(value: Object; dataType: DataType): String

static String serializeObject(Object value, DataType dataType)

Parameters:

value: The value that is to be converted to string.
dataType: The type of the provided value.

Size (declared in ParameterExpression)

property Size: Integer read write;

Integer Size { __get; __set; }

toSqlString (declared in WhereExpression)

A helper method that wraps the similar one with the string builder and returns a SQL string.

method toSqlString: String

String toSqlString()

toSqlString (StringBuilder)

Creates an SQL representation of constant expression and appends it to the provided StringBuilder.

method toSqlString(aDestination: StringBuilder)

void toSqlString(StringBuilder aDestination)

Parameters:

aDestination: The destination string builder that will contain the string representation of the list.

toString (declared in WhereExpression)

Returns a SQL string representation of the current expression.

method toString: String

String toString()

toXmlNode (declared in WhereExpression)

Creates a query node (in the Dynamic Where XML Format) from the current expression.

method toXmlNode: Node

Node toXmlNode()

toXmlString (declared in WhereExpression)

Creates the query node (in the Dynamic Where XML Format) from current expression and returns it in the string format.

method toXmlString: String

String toXmlString()

Type (declared in ParameterExpression)

property Type: DataType read write;

DataType Type { __get; __set; }

validate (declared in WhereExpression)

Validates the current expression with the WhereValidator and returns TRUE if it contains no errors. The main purpose of the validation is to scan all objects of WhereExpession tree and make sure that they contain correct field names.

method validate: Boolean

Boolean validate()

validate (WhereExpression): Boolean (declared in WhereExpression)

Validates the provided WhereExpression with the WhereValidator and returns TRUE if it contains no errors. The main purpose of the validation is to scan all objects of WhereExpession tree and make sure that it contains correct field names.

class method validate(anExpression: WhereExpression): Boolean

static Boolean validate(WhereExpression anExpression)

Parameters:

anExpression: The expression to be validated.

Value

property Value: Object read write;

Object Value { __get; __set; }

writeToXml

Creates Xml node (in the Dynamic Where XML Format) from the current ConstantExpression and appends it to the given parent node.

method writeToXml(aNode: Node)

void writeToXml(Node aNode)

Parameters:

aNode: The parent XML node.

Kind

property Kind: WhereKind read;

WhereKind Kind { __get; }

ParameterName (declared in ParameterExpression)

property ParameterName: String read write;

String ParameterName { __get; __set; }

Size (declared in ParameterExpression)

property Size: Integer read write;

Integer Size { __get; __set; }

Type (declared in ParameterExpression)

property Type: DataType read write;

DataType Type { __get; __set; }

Value

property Value: Object read write;

Object Value { __get; __set; }

combine (WhereExpression, WhereExpression): WhereExpression (declared in WhereExpression)

Creates a new BinaryExpression from the given aLeft and aRight operands using BinaryOperator.

class method combine(aLeft: WhereExpression; aRight: WhereExpression): WhereExpression

static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight)

Parameters:

aLeft: The left operand to be combined.
aRight: The right operand to be combined.

combine (WhereExpression, WhereExpression, BinaryOperator): WhereExpression (declared in WhereExpression)

Creates a new BinaryExpression from the given aLeft and aRight operands using the given operator.

class method combine(aLeft: WhereExpression; aRight: WhereExpression; anOperator: BinaryOperator): WhereExpression

static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight, BinaryOperator anOperator)

Parameters:

aLeft: The left operand to be combined.
aRight: The right operand to be combined.
anOperator: The operator to be used in combining.

deserializeObject

Returns the object of the given type from the given provided string.

class method deserializeObject(aSource: String; aDataType: DataType): Object

static Object deserializeObject(String aSource, DataType aDataType)

Parameters:

aSource: The string to be converted.
aDataType: The target type of the result value.

fromString (declared in WhereExpression)

Creates a new WhereExpression from the specified string, which should contain XML node in the correct Dynamic Where XML Format.

class method fromString(anXml: String): WhereExpression

static WhereExpression fromString(String anXml)

Parameters:

anXml: The given XML string.

fromStringToSql (declared in WhereExpression)

A helper method to convert a XML string into SQL string.

class method fromStringToSql(anXml: String): String

static String fromStringToSql(String anXml)

Parameters:

anXml: The XML string to be converted.

fromXmlNode (declared in WhereExpression)

Creates a new WhereExpression from the given XML node, which should be in the correct Dynamic Where XML Format.

class method fromXmlNode(aNode: Node): WhereExpression

static WhereExpression fromXmlNode(Node aNode)

Parameters:

aNode: The XML node to be parsed.

parseExpression (declared in WhereExpression)

class method parseExpression(node: Node): WhereExpression

static WhereExpression parseExpression(Node node)

Parameters:

node:

serializeObject

Returns a string representation of the given value in consideration of the specified type.

class method serializeObject(value: Object; dataType: DataType): String

static String serializeObject(Object value, DataType dataType)

Parameters:

value: The value that is to be converted to string.
dataType: The type of the provided value.

validate (WhereExpression): Boolean (declared in WhereExpression)

class method validate(anExpression: WhereExpression): Boolean

static Boolean validate(WhereExpression anExpression)

Parameters:

anExpression: The expression to be validated.

constructor

Creates an instance of ConstantExpression.

constructor

ConstantExpression()

constructor (String, DataType, Integer) (declared in ParameterExpression)

Creates a new instance of the ParameterExpression class with a specified name, type and size of the parameter.

constructor(aName: String; aType: DataType; aSize: Integer)

ConstantExpression(String aName, DataType aType, Integer aSize)

Parameters:

aName: The name of the parameter.
aType: The data type of the parameter.
aSize: The size of the parameter; used if applicable to the type.

constructor (Object)

Creates an instance of ConstantExpression with the given constant value.

constructor(aValue: Object)

ConstantExpression(Object aValue)

Parameters:

aValue: The value of the constant.

constructor (Object, DataType)

Creates an instance of ConstantExpression with the given value and data type.

constructor(aValue: Object; aType: DataType)

ConstantExpression(Object aValue, DataType aType)

Parameters:

aValue: The value of the constant.
aType: The type of the constant.

readFromXml

Initializes the current ConstantExpression from the given XML node.

method readFromXml(aNode: Node)

void readFromXml(Node aNode)

Parameters:

aNode: The node that contains the serialized expression.

toSqlString (declared in WhereExpression)

A helper method that wraps the similar one with the string builder and returns a SQL string.

method toSqlString: String

String toSqlString()

toSqlString (StringBuilder)

Creates an SQL representation of constant expression and appends it to the provided StringBuilder.

method toSqlString(aDestination: StringBuilder)

void toSqlString(StringBuilder aDestination)

Parameters:

aDestination: The destination string builder that will contain the string representation of the list.

toString (declared in WhereExpression)

Returns a SQL string representation of the current expression.

method toString: String

String toString()

toXmlNode (declared in WhereExpression)

Creates a query node (in the Dynamic Where XML Format) from the current expression.

method toXmlNode: Node

Node toXmlNode()

toXmlString (declared in WhereExpression)

Creates the query node (in the Dynamic Where XML Format) from current expression and returns it in the string format.

method toXmlString: String

String toXmlString()

validate (declared in WhereExpression)

method validate: Boolean

Boolean validate()

writeToXml

Creates Xml node (in the Dynamic Where XML Format) from the current ConstantExpression and appends it to the given parent node.

method writeToXml(aNode: Node)

void writeToXml(Node aNode)

Parameters:

aNode: The parent XML node.