Package org.vedantatree.expressionoasis.expressions

Class BinaryOperatorExpression

java.lang.Object

org.vedantatree.expressionoasis.expressions.BinaryOperatorExpression

All Implemented Interfaces:

Expression

Direct Known Subclasses:

AddExpression, AndExpression, ArgumentExpression, ArrayIndexExpression, BWAndExpression, BWOrExpression, BWSignedLeftShiftExpression, BWSignedRightShiftExpression, BWUnsignedRightShiftExpression, BWXorExpression, ConditionTernaryExpression, ContainsExpression, DivideExpression, EndsWithExpression, EQExpression, GTEExpression, LTEExpression, MaxExpression, MinExpression, MultiplyExpression, OrExpression, PropertyExpression, RemainderExpression, ResultTernaryExpression, StartsWithExpression, SubtractExpression

public abstract class BinaryOperatorExpression
extends Object
implements Expression

This class defines the abstract implemenation for binary operator expression.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	BinaryOperatorExpression.TypePair	This is the class for making pair of valid types for a binary operator.

Field Summary

Fields

Modifier and Type	Field	Description
protected Expression	leftOperandExpression	Left operand expression for this binary operator expression.
protected Expression	rightOperandExpression	Right operand expression for this binary operator expression.

Constructor Summary

Constructors

Constructor	Description
BinaryOperatorExpression()

Method Summary

Modifier and Type	Method	Description
void	accept(ExpressionVisitor visitor)	Allows an expression visitor to visit this expression and it's sub-expressions (implements Visitor design pattern).
protected static void	addTypePair(Class clazz, Type leftType, Type rightType, Type resultType)	Adds the type mapping for the given operator.
protected static BinaryOperatorExpression.TypePair	createTypePair(Type leftType, Type rightType)	Creates the type pair for given types pair
Expression	getLeftOperandExpression()	Gets the value of leftOperandExpression.
Type	getReturnType()	Gets the return type of the expression.
Expression	getRightOperandExpression()	Gets the value of rightOperandExpression.
ValueObject	getValue()	Executes and returns the value of this expression.
void	initialize(ExpressionContext expressionContext, Object parameters, boolean validate)	Initializes the child expressions.
String	toString()
void	uninitialize(ExpressionContext expressionContext)	Uninitializes the binary expression.
protected void	validate(ExpressionContext expressionContext)	Validates the expression.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

leftOperandExpression

protected Expression leftOperandExpression

Left operand expression for this binary operator expression.

rightOperandExpression

protected Expression rightOperandExpression

Right operand expression for this binary operator expression.

Constructor Detail

BinaryOperatorExpression

public BinaryOperatorExpression()

Method Detail

initialize

public void initialize(ExpressionContext expressionContext,
                       Object parameters,
                       boolean validate)
                throws ExpressionEngineException

Initializes the child expressions.

Specified by:

initialize in interface Expression

Parameters:

expressionContext - contextual information, may help in initialization

parameters - for example, sub expressions and identifiers

Throws:

ExpressionEngineException - if there is any problem during execution

See Also:

org.vedantatree.expressionoasis.expressions.Expression#initialize(org.vedantatree.expressionoasis.ExpressionContext, java.lang.Object)

getReturnType

public Type getReturnType()
                   throws ExpressionEngineException

Description copied from interface: Expression

Gets the return type of the expression.

Specified by:

getReturnType in interface Expression

Returns:

the type of expression

Throws:

ExpressionEngineException - If there is any problem during execution

See Also:

Expression.getReturnType()

getLeftOperandExpression

public Expression getLeftOperandExpression()

Gets the value of leftOperandExpression.

Returns:

Returns the leftOperandExpression.

getRightOperandExpression

public Expression getRightOperandExpression()

Gets the value of rightOperandExpression.

Returns:

Returns the rightOperandExpression.

uninitialize

public void uninitialize(ExpressionContext expressionContext)

Uninitializes the binary expression.

Specified by:

uninitialize in interface Expression

Parameters:

expressionContext - contextual information, may help in un-initialization

See Also:

Expression.uninitialize(org.vedantatree.expressionoasis.ExpressionContext)

createTypePair

protected static final BinaryOperatorExpression.TypePair createTypePair(Type leftType,
                                                                        Type rightType)

Creates the type pair for given types pair

Parameters:

leftType -

rightType -

Returns:

addTypePair

protected static final void addTypePair(Class clazz,
                                        Type leftType,
                                        Type rightType,
                                        Type resultType)

Adds the type mapping for the given operator. User can add as many mapping as required for operator. Like in case of '+' operator, one possible mapping is left type = integer, right type = string, result type = string. Because if we add integer to string, it will result in a string value.

Parameters:

clazz - class of the operator like +, - etc

leftType - type of left operand

rightType - type of right operand

resultType - type of result

validate

protected void validate(ExpressionContext expressionContext)
                 throws ExpressionEngineException

Validates the expression.

Parameters:

expressionContext -

Throws:

ExpressionEngineException

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

accept

public void accept(ExpressionVisitor visitor)

Allows an expression visitor to visit this expression and it's sub-expressions (implements Visitor design pattern).

Specified by:

accept in interface Expression

Parameters:

visitor - a visitor object that this expression must visit when accept is called.

See Also:

Expression.accept(org.vedantatree.expressionoasis.ExpressionVisitor)

getValue

public ValueObject getValue()
                     throws ExpressionEngineException

Description copied from interface: Expression

Executes and returns the value of this expression. If expression is not at node level, it will further evaluate its related expression which may represents operands or operators and return the final outcome.

Specified by:

getValue in interface Expression

Returns:

the value of expression (after expression evaluation)

Throws:

ExpressionEngineException - if there is any problem during execution