com.sdmetrics.math

Class ExpressionNode

java.lang.Object

com.sdmetrics.math.ExpressionNode

public class ExpressionNode
extends java.lang.Object

Represents a node in the operator tree for a math expression.

Constructor Summary

Constructors

Constructor and Description
ExpressionNode(java.lang.String identifier) Creates a new node representing an identifier.

Method Summary

Modifier and Type	Method and Description
ExpressionNode	getLeftNode() Retrieves the node representing the left hand side of a binary operation, or the operand of a unary operation.
ExpressionNode	getOperand(int index) Gets an operand of the node.
int	getOperandCount() Gets the number of operands of this node.
ExpressionNode	getRightNode() Retrieves the node representing the right hand side of a binary operation.
java.lang.String	getValue() Retrieves the value of this node.
boolean	isIdentifier() Tests whether this node represents an identifier.
boolean	isNumberConstant() Tests whether this node represents a number constant.
boolean	isOperation() Tests whether this node represents an operation.
boolean	isStringConstant() Tests whether this node represents a string constant.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpressionNode

public ExpressionNode(java.lang.String identifier)

Creates a new node representing an identifier.

Parameters:

identifier - The identifier

Method Detail

getValue

public java.lang.String getValue()

Retrieves the value of this node. The meaning of the value depends on the node type:

• For operations, the value is a string indicating the operation: +,-, etc or a function or relation name.
• For numbers, the value is the string representation of the number.
• For string constants, the value is the constant string (without the single quotes).
• For identifiers, the value is the identifier.

Returns:

value of the node

getOperandCount

public int getOperandCount()

Gets the number of operands of this node.

Returns:

The number of operands of this node

Since:

2.3

getOperand

public ExpressionNode getOperand(int index)

Gets an operand of the node.

Parameters:

index - Index of the operand. Valid indices run from 0 to getOperandCount().

Returns:

The operand at the given index.

Throws:

java.lang.IllegalArgumentException - Index out of range

Since:

2.3

getLeftNode

public ExpressionNode getLeftNode()

Retrieves the node representing the left hand side of a binary operation, or the operand of a unary operation. Convenience method for unary/binary operations.

Returns:

the left node, or null if there is no left operand

getRightNode

public ExpressionNode getRightNode()

Retrieves the node representing the right hand side of a binary operation. Convenience method for binary operations.

Returns:

the right node, or null if there is no right operand

isOperation

public boolean isOperation()

Tests whether this node represents an operation.

Returns:

true if this node represents an operation.

isNumberConstant

public boolean isNumberConstant()

Tests whether this node represents a number constant.

Returns:

true if this node represents a number constant.

isStringConstant

public boolean isStringConstant()

Tests whether this node represents a string constant.

Returns:

true if this node represents a string constant.

isIdentifier

public boolean isIdentifier()

Tests whether this node represents an identifier.

Returns:

true if this node represents an identifier.